〇Product structure :Silicon and silicon carbide integrated circuit 〇This product has no designed protection against radioactive rays
.
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TSZ02201-0F1F0A200470-1-2
© 2018 ROHM Co., Ltd. All rights reserved.
03.Apr.2019 Rev.002
TSZ22111 • 14 • 001
www.rohm.com
Quasi-resonant AC/DC Converter
Built-in 1700 V SiC-MOSFET
BM2SCQ12xT-LBZ Series
General Description
This is the product guarantees long time support in
industrial market.
BM2SCQ12xT-LBZ series is a quasi-resonant AC/DC
converter that provides an optimum system for all
products which has an electrical outlet. Quasi-resonant
operation enables soft switching and helps to keep the
EMI low.
This IC can be designed easily because it includes the
1700 V/4 A SiC (Silicon-Carbide) MOSFET.
Design with a high degree of flexibility is achieved with
current detection resistors as external devices. The burst
operation reduces an input power at light load.
BM2SCQ12xT-LBZ series includes various protection
functions, such as soft start function, burst operation,
over current limiter per cycle, over-voltage protection
function, overload protection function.
Features
Long Time Support Product for Industrial Applications
6 Pins: TO220-6M Package
Built-in 1700 V/4 A/1.2 Ω SiC-MOSFET
Quasi-resonant Type (Low EMI)
Frequency Reduction Function
Low Current Consumption (19 µA) during Standby
Burst Operation at Light Load
SOURCE Pin Leading Edge Blanking
VCC UVLO (Under Voltage Drop Out protection)
VCC OVP (Over Voltage Protection)
Over Current Protection Circuit per Cycle
Soft Start Function
ZT Pin Trigger Mask Function
ZT OVP (Over Voltage Protection)
Key Specifications
Operating Power Supply Voltage Range:
VCC: 15.0 V to 27.5 V
DRAIN: 1700 V (Max)
Normal Operating Current: 2000 µA (Typ)
Burst Operating Current: 500 µA (Typ)
Maximum Operating Frequency: 120 kHz (Typ)
Operating Temperature: -40 °C to +105 °C
Package W (Typ) x D (Typ) x H (Max)
TO220-6M 10.0 mm x 4.5 mm x 25.6 mm
Applications
Power Supply for Industrial Equipment, AC Adaptor,
Household Appliances
Lineup
Product name
FB OLP
VCC OVP
BM2SCQ121T-LBZ
Auto Restart
Latch
BM2SCQ122T-LBZ
Latch
Latch
BM2SCQ123T-LBZ
Auto Restart
Auto Restart
BM2SCQ124T-LBZ
Latch
Auto Restart
Typical Application Circuit
GND
DRAIN SOURCE
ERROR
AMP
FB ZT VCC
FUSE
Filter Diode
Bridge
Datashee
t
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TSZ02201-0F1F0A200470-1-2
© 2018 ROHM Co., Ltd. All rights reserved.
03.Apr.2019 Rev.002
BM2SCQ12xT-LBZ Series
www.rohm.com
TSZ22111 • 15 • 001
Pin Configuration (TOP VIEW)
Pin Description
Pin No.
Pin Name
I/O
Function
ESD Diode
VCC
GND
1
DRAIN
I/O
MOSFET DRAIN pin
-
✔
2
SOURCE
I
MOSFET SOURCE pin
✔
✔
3
FB
I
Feedback signal input pin
✔
✔
4
GND
I/O
GND pin
✔
-
5
ZT
I
Zero current detection pin
-
✔
6
VCC
I
Power supply input pin
-
✔
Block Diagram
GND
DRAIN SOURCE FB ZT VCC
1 2 3 4 5 6
NOUT
+
-
+
VOUT
Filter Diode
Bridge
Leading Edge
Blanking
GND
VCC
SOURCE
+
-
Internal
Supply
ZT ZT
Comp.
RS
CZT
FB
VREF(4 V)
AND
18.5 V/14.0 V
28.0 V
Timer
(128 ms)FBOLP_OH
+
-
100 mV
/400 mV
1 shot
OSC
CFB
PC
OSC
RZT1
7 V
AND
ZT
Blanking
OUT(H->L)
0.60 µs NOUT
Time Out
( 45 µs ) AND PRE
Driver
POUT
FB/2
+
-
-
DCDC
Comp.
1.00 V
+
-VCC OVP
CURRENT SENSE (V-V Change)
Normal: ｘ 1.0
+
-
FBOLP_OH
1.00 V
0.50 V
+
-
OLP
200 kΩ
200 kΩ
VCC UVLO
Burst
Comp.
4.0 V
Regulator
Soft Start
20 kΩ
+
-ZT ACSNS Comp.
Va
RSTART
CVCC
VH
RZT2
+
-ZT OVP Comp.
(LATCH)
SQ
R
NOUT 18.0 V
Clamper
DRAIN 1
1700 V
SiC-MOSFET
ERROR
AMP
OR
OR
Maximum
Blanking
Frequency
(120 kHz)
FUSE
2
4
3
5
6
OUT
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TSZ02201-0F1F0A200470-1-2
© 2018 ROHM Co., Ltd. All rights reserved.
03.Apr.2019 Rev.002
BM2SCQ12xT-LBZ Series
www.rohm.com
TSZ22111 • 15 • 001
Description of Blocks
1 Startup Sequences (FB OLP: Auto Recovery Mode)
The BM2SCQ12xT-LBZ’s startup sequence is shown in Figure 1.
See the sections below for the detailed descriptions.
Figure 1. Startup Sequence Timing Chart
A: The input voltage VH is applied.
B: The VCC pin voltage rises due to start resistor RSTART, and this IC starts operating when the VCC pin voltage
becomes higher than VUVLO1 (Typ = 19.5 V). When the protection functions are judged as normal status, the
switching operation starts. At that time, since the VCC pin voltage value always drops due to the pin's consumption
current, it is necessary to set the VCC pin voltage to higher than VUVLO2 (Typ = 14.0 V).
C: The IC has a soft start function which regulates the voltage level at the SOURCE pin to prevent an excessive rise in
voltage and current.
D: When the switching operation starts, VOUT rises. At startup, the output voltage should be set to the regulated voltage
within tFOLP period (Typ = 128 ms).
E: At a light load, the IC starts burst operation in order to keep power consumption down.
F: Overload operation.
G: When the FB pin voltage keeps being more than VFOLP1 (Typ = 2.8 V) for tFOLP (Typ = 128 ms) or more, the switching
operation is stopped by the overload protection circuit. If the FB pin voltage status becomes less than VFOLP2(Typ =
2.6 V) even once, tFOLP (Typ = 128 ms) timer is reset
H: When the VCC pin voltage becomes VUVLO2 (Typ = 14.0 V) or less, restart is executed.
I: The IC’s circuit current is reduced and the VCC pin voltage rises. (Same as B)
J: Same as F.
K: Same as G.
VOUT
Switching
Input
Voltage
VH
VCC Pin
Voltage
19.5 V
FB Pin
Voltage
Soft Start
IOUT
Normal
Load Light
Load
128 ms
14.0 V
Over
Load
Internal REF
Pull Up
Burst Mode
VFLOP1
ABCDEFGH I JK
128 ms128 ms
VFLOP2
Time
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TSZ02201-0F1F0A200470-1-2
© 2018 ROHM Co., Ltd. All rights reserved.
03.Apr.2019 Rev.002
BM2SCQ12xT-LBZ Series
www.rohm.com
TSZ22111 • 15 • 001
1 Startup Sequences (FB OLP: Auto Recovery Mode) – continued
Start resistance RSTART is the resistance required to start the IC. If the start resistance RSTART value is set to low, the
standby power becomes large and the startup time becomes short. Conversely, if the start resistance RSTART value is set
to large, standby power becomes low and the startup time becomes long. The standby current IOFF of
BM2SCQ12xT-LBZ is 30 µA (Max). However, this is the minimum current required to start the IC. It is necessary to set
the appropriate current value for the set target.
e.g. Start Resistance RSTART Setting
[Ω]
Where:
is the start resistance.
is the minimum AC voltage.
is the VCC UVLO voltage.
is the standby current.
When the AC input voltage is AC 80 V, VMIN = 113 V.
And it can be calculated as (113 - 20)/30 μA = 3.1 MΩ because VUVLO1 (Max) = 20.0 V at this time.
Considering the optimal value for the resistor which is 3.1 MΩ or less and set RSTART to 3.0 MΩ.
The power dissipation at this time is calculated by the formula below.
[mW]
Where:
is the power dissipation.
is the start resistance.
is the input voltage.
is the IC power supply voltage.
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TSZ02201-0F1F0A200470-1-2
© 2018 ROHM Co., Ltd. All rights reserved.
03.Apr.2019 Rev.002
BM2SCQ12xT-LBZ Series
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TSZ22111 • 15 • 001
Description of Blocks – continued
2 VCC Pin Protection Function
BM2SCQ12xT-LBZ includes the VCC low voltage protection function VCC UVLO and the VCC over voltage protection
function VCC OVP. These functions prevent the abnormal voltage-related break in MOSFETs used for switching. The
VCC UVLO function is an auto recovery type comparator with voltage hysteresis and the VCC OVP function is the
comparator uses latch mode or auto recovery mode. After latch function is detected by VCC OVP, latching is released
(reset) when the condition the VCC pin voltage < VLATCH (Typ = VUVLO2 - 3.5 V) is met. This operation is shown in Figure
2. And VCC OVP has a built-in mask time tLATCH (Typ = 150 µs). This function masks such as the surges occur at the pin.
Figure 2. VCC UVLO/OVP (Latch Mode)
A: VH is applied, the VCC voltage rises.
B: When the VCC pin voltage is higher than VUVLO1 (Typ = 19.5 V), the switching operation starts.
C: When the VCC pin voltage is lower than VUVLO2 (Typ = 14.0 V), the switching operation stops.
D: When the VCC pin voltage is higher than VUVLO1 (Typ = 19.5 V), the switching operation starts.
E: The VCC pin voltage drops until the output voltage is stabilized.
F: The VCC pin voltage rises.
G: When the VCC pin voltage is higher than VOVP1 (Typ = 29.5 V), the switching is stopped by an internal latch signal.
H: When the switching operation stops, power supply from the auxiliary coil stops and the VCC pin voltage drops.
I: When the VCC pin voltage is lower than VUVLO2 (Typ = 14.0 V), the VCC pin voltage rises because the IC current
consumption current drops.
J: When the VCC pin voltage is higher than VUVLO1 (Typ = 19.5 V), there are no switching operations because the IC is
during latch operation. The VCC pin voltage drops because the IC current consumption current is lowered.
K: Same as H.
L: Same as I.
M: VH is OPEN (unplugged). The VCC pin voltage drops.
N: When the VCC pin voltage < VLATCH (Typ = VUVLO2 -3.5 V), it is latch-released.
VUVLO1
OFF
ON
OFF
ON
Switching
VCC UVLO
ON
OFF
ON
OFF
VCC OVP
OFF
ON
OFF
ABC D EF
OFF
Internal
Latch Signal
L : Normal
H : Latch
Input
Voltage
VH
GH I J K L M
VLATCH
N A Time
B
VUVLO2
VCC Pin
Voltage
VOVP1
0 V
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TSZ02201-0F1F0A200470-1-2
© 2018 ROHM Co., Ltd. All rights reserved.
03.Apr.2019 Rev.002
BM2SCQ12xT-LBZ Series
www.rohm.com
TSZ22111 • 15 • 001
Description of Blocks – continued
3 DC/DC Converter Function
BM2SCQ12xT-LBZ uses PFM (Pulse Frequency Modulation) mode control. The FB pin, the ZT pin, and the SOURCE
pin are monitored to provide a system optimized as DC/DC. The switching MOSFET ON width (turn OFF) is controlled
by the FB pin and the SOURCE pin, and the OFF width (turn ON) is controlled by the ZT pin. By setting maximum
frequency, PFM mode will control it to meet noise regulation. A detailed description is below. (Refer to Figure 3)
Figure 3. Block Diagram of DC/DC Operations
NOUT
+
-
+
Leading Edge
Blanking
GND
VCC
SOURCE
ZT ZT
Comp.
RS
CZT
FB
VREF(4 V)
Timer
(128 ms)FBOLP_OH
+
-
100m V
/400m V
1 shot
CFB
RZT1
7 V
AND
ZT Blanking
OUT(H→L)
0.60 µs NOUT
Time Out
( 45 µs ) AND
AND PRE
Driver
POUT
FB/2
+
-
-
DCDC
Comp.
1.00 V
CURRENT SENSE (V-V Change)
Normal: x 1.0
+
-
FBOLP_OH
Maximum
Blanking
Frequency
(120 kHz)
1.00 V
0.50V
+
-
OLP
200 kΩ
200 kΩ
Burst
Comp.
Soft Start
20 kΩ
+
-ZT ACSNS Comp.
Va
RSTART
CVCC
VH
RZT2
+
-ZT OVP Comp.
(LATCH)
SQ
R
NOUT 18.0 V
Clamper
DRAIN 1
1700 V
SiC-MOSFET
2
4
3
5
6
OR
OR
OUT
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TSZ02201-0F1F0A200470-1-2
© 2018 ROHM Co., Ltd. All rights reserved.
03.Apr.2019 Rev.002
BM2SCQ12xT-LBZ Series
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TSZ22111 • 15 • 001
3 DC/DC Converter Function – continued
3.1 Determination of ON Width (Turn OFF)
ON width is controlled by the FB pin and SOURCE pin. The ON width is determined by comparing the FB pin
voltage at 1/AV (Typ = 1/2) with the SOURCE pin voltage. In addition, the comparator level is changed by
comparing with the IC's internally generated VLIM1A (Typ = 1.0 V), as is shown in Figure 4. The SOURCE pin is also
used for the over current limiter circuit per pulse. Changes at the FB pin changes in the maximum blanking
frequency and over current limiter level.
mode 1: Burst operation
mode 2: Frequency reduction operation (reduces maximum frequency)
mode 3: Maximum frequency operation (operates at maximum frequency)
mode 4: Overload operation (pulse operation is stopped when overload is detected)
Figure 4. Relationship of FB Pin Voltage to Over Current Limiter and Maximum Frequency
The switch of over current protection in the soft start function and input voltage is performed by adjusting the
over current limiter lever. In this case, the VLIM1 and VLIM2 values are as listed below.
Table 1. Over Current Protection Voltage
Soft Start
IZT ≥ -1.0 mA
IZT < -1.0 mA
VLIM1A
VLIM2A
VLIM1B
VLIM2B
from startup to less than 1 ms
0.250 V (25.0 %)
0.063 V (6.3 %)
0.175 V (17.5 %)
0.047 V (4.7 %)
from 1 ms to less than 4 ms
0.500 V (50.0 %)
0.125 V (12.5 %)
0.350 V (35.0 %)
0.094 V (9.4 %)
4 ms or more
1.000 V (100.0 %)
0.250 V (25.0 %)
0.700 V (70.0 %)
0.188 V (18.8 %)
(Note) Values those compared to VLIM1A (Typ = 1.0 V) during IZT ≥ -1.0 mA are shown in ().
3.2 L.E.B. (Leading Edge Blanking) Function
When the switching MOSFET is turned ON, surge current occur at each capacitor component and drive current.
Therefore, when the SOURCE pin voltage rises temporarily, detection errors may occur in the over current limiter
circuit. To prevent detection errors, BM2SCQ12xT-LBZ has the blanking function. This function masks the
SOURCE pin voltage for tLEB (Typ = 250 ns) after the DRAIN pin changes from high to low. This blanking function
reduces the SOURCE pin noise filter.
FB Pin
Voltage
[V]
Maximum Operating
Frequency [kHz]
0.5 1.25
fSW2
fSW1
0.0 2.0
mode 1 mode 2 mode 3
2.8
mode 4
0.50.0 2.0
mode 1 mode 2 mode 3
2.8
mode 4
CS
Limiter [V]
VLIM1
VLIM2
1.25
FB Pin
Voltage
[V]
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TSZ02201-0F1F0A200470-1-2
© 2018 ROHM Co., Ltd. All rights reserved.
03.Apr.2019 Rev.002
BM2SCQ12xT-LBZ Series
www.rohm.com
TSZ22111 • 15 • 001
3 DC/DC Converter Function – continued
3.3 SOURCE Over Current Protection Switching Function
When the input voltage (VH) becomes high, the ON time is shortened and the operating frequency increases. As a
result, the maximum rated power is increased for a certain over current limiter. As a countermeasure, the IC will use
its internal over current protection function to switch. In case of high voltage, the over current comparator value
which determines the ON time is multiplied by 0.7 of normal operation.
Detection and switch are performed by monitoring the ZT inflow current. When the MOSFET is turned ON, Va
becomes a negative voltage dependent on the input voltage (VH). The ZT pin is clamped to nearly 0 V in the IC.
The formula used to calculate this is shown below. A block diagram is shown in Figure 5. Also, graphs are shown in
Figure 6, Figure 7 and Figure 8.
[A]
[Ω]
Where:
is the ZT inflow current.
is the auxiliary winding voltage.
is the ZT pin voltage.
is the ZT pin resistance 1.
is the input voltage.
is the primary side winding.
is the auxiliary winding.
From the above, the VH voltage is set with a resistance value (RZT1). The ZT bottom detection voltage is determined
at that time, therefore, set the timing with CZT.
Figure 5. Block Diagram of SOURCE Switching Current
NOUT
+
-
+
Leading Edge
Blanking
GND
VCC
SOURCE
ZT
ZT
Comp.
RS
CZT
FB
VREF(4 V)
Timer
(128 ms)FBOLP_OH
+
-
100m V
/400m V
1 shot
CFB
RZT1
7 V
AND
ZT Blanking
OUT(H→L)
0.60 µs NOUT
Time Out
( 45 µs ) AND
AND PRE
Driver
POUT
FB/2
+
-
-
DCDC
Comp.
1.00 V
CURRENT SENSE (V-V Change)
Normal: x 1.0
+
-
FBOLP_OH
Maximum
Blanking
Frequency
(120 kHz)
1.00 V
0.50V
+
-
OLP
200 kΩ
200 kΩ
Burst
Comp.
Soft Start
20 kΩ
+
-ZT ACSNS Comp.
Va
RSTART
CVCC
VH
RZT2
+
-ZT OVP Comp.
(LATCH)
SQ
R
NOUT 18.0 V
Clamper
DRAIN 1
2
4
3
5
6
OR
OR
IZT =(VH x Na)/(Np x RZT1)
OUT
9/29
TSZ02201-0F1F0A200470-1-2
© 2018 ROHM Co., Ltd. All rights reserved.
03.Apr.2019 Rev.002
BM2SCQ12xT-LBZ Series
www.rohm.com
TSZ22111 • 15 • 001
3.3 SOURCE Over Current Protection Switching Function – continued
Figure 6. SOURCE Switching: SOURCE Limiter vs FB Pin Voltage
Figure 7. SOURCE Switching: SOURCE Limiter vs ZT Pin Current
e.g. Setup method (for switching between 100 V AC and 220 V AC.)
100 V AC: 141 V ±42 V (±30 % margin)
220 V AC: 308 V ±62 V (±20 % margin)
In the above cases, the SOURCE current is switched in the range from 182 V to 246 V.
→ This is done when VH = 214 V.
Given: Np = 100, Na = 15.
[V]
[kΩ]
Where:
is the auxiliary winding voltage.
is the input voltage.
is the primary side winding.
is the auxiliary side winding.
is the ZT pin resistance.
is the ZT pin inflow current.
According to the above, RZT = 32 kΩ is set.
Figure 8. Example of SOURCE Switching: SOURCE Limiter vs VH Pin Voltage
X
Y
FB pin voltage [V]
0.5 1.0
0.0 1.5 2.0
mode 1 mode 2 mode 3
2.8
mode 4
SOURCE
Limiter [V]
IZT ≥ -1.0 mA IZT < -1.0 mA
VLIM2B
VLIM2A
VLIM1A
VLIM1B
X
Y
ZT Pin Current [mA]
SOURCE
Limiter [V]
VLIM1
VLIM1 x 0.7
1.0
X
Y
VH Pin Voltage [V]
SOURCE
Limiter [V]
VLIM1
VLIM1 x 0.7
214
10/29
TSZ02201-0F1F0A200470-1-2
© 2018 ROHM Co., Ltd. All rights reserved.
03.Apr.2019 Rev.002
BM2SCQ12xT-LBZ Series
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TSZ22111 • 15 • 001
3 DC/DC Converter Function – continued
3.4 Determination of OFF Width (Turn ON)
The OFF width is controlled at the ZT pin. While switching is OFF, the power stored in the coil is supplied to the
secondary side output capacitor. When this power supply ends, there is no more current flowing to the secondary
side, so the DRAIN pin of switching MOS voltage drops. Consequently, the voltage on the auxiliary coil side also
drops.
A voltage that was resistance-divided by RZT1 and RZT2 is applied to the ZT pin. When this voltage level drops to
VZT1 (Typ = 100 mV) or below, switching is turned ON by the ZT comparator. To detect zero current status at the ZT
pin, time constants are generated using CZT, RZT1, and RZT2. Additionally, the ZT trigger mask and the ZT timeout
function are built-in.
3.5 ZT Pin Trigger Mask Function
When the switching is set OFF from ON, superposition of noise may occur at the ZT pin. At this time, the ZT
comparator is masked for the tZTMASK (Typ = 0.60 µs) to prevent the ZT comparator operate errors. (Refer to Figure
9)
Figure 9. ZT Pin Trigger Mask Function
A: Switching is OFF→ON
B: Switching is ON→OFF
C: Because noise occurs at the ZT pin, the ZT comparator is not operated during tZTMASK (Typ = 0.60 µs).
D: Same as A.
E: Same as B.
F: Same as C.
G: Same as A.
OUT
Switching ON OFF ON OFF
ZT Pin
Voltage
ZT Trigger
Mask Pin
ON
tZMASK
A B C D E F G
tZMASK
Time
11/29
TSZ02201-0F1F0A200470-1-2
© 2018 ROHM Co., Ltd. All rights reserved.
03.Apr.2019 Rev.002
BM2SCQ12xT-LBZ Series
www.rohm.com
TSZ22111 • 15 • 001
3 DC/DC Converter Function – continued
3.6 ZT Timeout Function
ZT Timeout Function 1
When the ZT pin voltage is not higher than VZT2 (Typ = 200 mV) during tZTOUT1 (Typ = 45 µs) because of the
decrease of output voltage or the shorted ZT pin such as at startup, this function turns on the switching by
force.
ZT Timeout Function 2
After the ZT comparator detects the bottom, the IC turns on MOSFET by force when the IC does not operate
next detection within tZTOUT2 (Typ = 5.0 µs). After the ZT comparator detected signal once, this function
operates. For that, it does not operate at startup or at low output voltage. When the IC is not able to detect
bottom by decreasing auxiliary winding voltage, the function operates.
Figure 10. ZT Timeout Function
A: At startup, the IC starts to operate by ZT timeout function1 because of the ZT pin voltage is 0 V.
B: MOSFET turns ON.
C: MOSFET turns OFF.
D: The ZT pin voltage drops to lower than VZT2 (Typ = 200 mV) by the oscillation decreasing.
E: MOSFET turns ON after tZTOUT2 (Typ = 5.0 µs) from D point by ZT timeout function 2.
F: The ZT pin voltage drops to lower than VZT2 (Typ = 200 mV) by the oscillation decreasing.
G: MOSFET turns ON after tZTOUT2 (Typ = 5.0 µs) from F point by ZT timeout function 2.
H: The ZT pin is shorted to GND.
I: MOSFET turns ON after tZTOUT1 (Typ = 45.0 µs) by ZT timeout function 1.
DRAIN
Pin Voltage
SOURCE
Pin Voltage
Bottom
Detection
ZT Pin
voltage VZT2
VZT1
ZT pin GND
short
5 µs
Timeout
45 µs45 µs
45 µs
Timeout
A
5 µs 5 µs
Time
BC D E F G H I
12/29
TSZ02201-0F1F0A200470-1-2
© 2018 ROHM Co., Ltd. All rights reserved.
03.Apr.2019 Rev.002
BM2SCQ12xT-LBZ Series
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TSZ22111 • 15 • 001
Description of Blocks – continued
4 Soft Start Function
Normally, a large current flows to the AC/DC power supply when the AC power supply is turned ON. BM2SCQ12xT-LBZ
includes a soft start function to prevent large changes in the output voltage current during startup. This function is
performed when the VCC pin voltage drops to VUVLO2 (Typ = 14.0 V) or less.
Soft start function performs the following operation after startup. (Refer to turn OFF described above in section 3.1).
･ from startup to less than 1 ms → Set the SOURCE limiter value to 25 % of normal
･ from 1 ms to less than 4 ms → Set the SOURCE limiter value to 50 % of normal
･ 4 ms or more → Normal operation
5 Over Load Protection Function
The overload protection function monitors the overload status of the secondary output current at the FB pin and fixes the
OUT pin at low level when the overload status is detected. During overload status, current no longer flows to the
photo-coupler, so the FB pin voltage rises. When this status continues for the tFOLP (Typ = 128 ms), it judges the status
as an overload and the OUT pin is fixed at low level. If the FB pin voltage drops to lower than VFOLP2 (Typ = 2.6 V) within
tFOLP (Typ = 128 ms) after once it exceeds VFOLP1 (Typ = 2.8 V), the overload protection timer is reset.
At startup, the FB pin voltage is pulled up to the internal voltage by a pull-up resistor, so operation starts from VFOLP1
(Typ = 2.8 V) or above. Therefore, it is necessary for the design to set the FB pin voltage at VFOLP2 (Typ = 2.6 V) or below
within tFOLP (Typ = 128 ms). In other words, the startup time of the secondary output voltage must be set to within tFOLP
(Typ = 128 ms) after the IC starts.
To release latching at selecting latch mode is operated when the VCC pin voltage becomes lower than VLATCH (Typ =
VUVLO2 - 3.5 V) by unplugging power supply.
6 ZT OVP (Over Voltage Protection)
ZT OVP (Over Voltage Protection) function is built-in the ZT pin. When the ZT pin voltage reaches VZTL (Typ = 3.5 V), this
function operates detection. The ZT pin OVP function is performed in latch mode.
ZT OVP function has a built-in mask time defined as tLATCH (Typ = 150 µs). This operates detection when ZT OVP status
continues for tLATCH (Typ = 150 µs). This function masks such as surges those occur at the pin. Refer to Figure 11. (A
similar tLATCH (Typ = 150 µs) is built-in VCC OVP.)
Figure 11. ZT OVP and Latch Mask Function
A: Switching turns ON and the ZT pin starts pulse operation.
B: The ZT pin voltage > VZTL (Typ = 3.5 V).
C: The status of the ZT pin voltage > VZTL (Typ = 3.5 V) is within tLATCH (Typ = 150 µs), so the switching is reset to
the normal operations.
D: The ZT pin voltage > VZTL (Typ = 3.5 V).
E: The status of ZT pin voltage > VZTL (Typ = 3.5 V) continues for tLATCH (Typ = 150 µs), so latching occurs and the
switching turned OFF.
Switching ON OFF
ZT Pin
Voltage
AC
B
PULSE
D E
VZTL
ΔT1 < tLATCH (Typ = 150 µs) ΔT2 = tLATCH (Typ = 150 µs)
ΔT1 ΔT2
PULSE
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TSZ22111 • 15 • 001
Description of Blocks – continued
7 Thermal Shutdown Function
Thermal Shutdown function is auto restart type. When VCC UVLO is released, the IC starts from state 2 because of
preventing from thermal destruction of external parts. At startup, it does not start until the temperature becomes T1 or
below. (Refer to Figure 12.)
Figure 12. Thermal Shutdown Function
Operation Modes of Protection Circuit
Table 2 below lists the operation modes of the various protection functions.
Table 2. Operation Modes of Protection Circuit
Item
Operation Mode
VCC Under Voltage Locked Out
Auto recovery
VCC Over Voltage Protection
BM2SCQ121T-LBZ/BM2SCQ123T-LBZ = Auto recovery
BM2SCQ122T-LBZ/BM2SCQ124T-LBZ = Latch
FB Over Limited Protection
BM2SCQ121T-LBZ/BM2SCQ122T-LBZ = Auto recovery
BM2SCQ123T-LBZ/BM2SCQ124T-LBZ = Latch
ZT Over Voltage Protection
Latch
Thermal Shutdown
Auto recovery
Temperature [°C]
T2 = 185 °C
(Typ)
T1 = 135 °C
(Typ)
State 2
State 1
OFF
ON
Switching
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TSZ22111 • 15 • 001
0.0
0.5
1.0
1.5
2.0
025 50 75 100 125 150
Pd[W]
Ta[℃]
Absolute Maximum Ratings (Ta = 25 °C)
Parameter
Symbol
Rating
Unit
Conditions
Maximum Applied Voltage 1
VMAX1
-0.3 to +32
V
The VCC pin
Maximum Applied Voltage 2
VMAX2
-0.3 to +6.5
V
The SOURCE, FB, ZT pin
Maximum Applied Voltage 3
VMAX3
-0.3 to +1700
V
The DRAIN pin
ZT Pin Maximum Current
ISZT
±3.0
mA
Power Dissipation
Pd
1.50
W
(Note 1)
Maximum Junction Temperature
Tjmax
150
°C
Storage Temperature Range
Tstg
-55 to +150
°C
Caution 1: Operating the IC over the absolute maximum ratings may damage the IC. The damage can either be a short circuit between pins or an open circuit
between pins and the internal circuitry. Therefore, it is important to consider circuit protection measures, such as adding a fuse, in case the IC is
operated over the absolute maximum ratings.
Caution 2: Should by any chance the maximum junction temperature rating be exceeded the rise in temperature of the chip may result in deterioration of the
properties of the chip. In case of exceeding this absolute maximum rating, design a PCB with power dissipation taken into consideration by increasing
board size and copper area so as not to exceed the maximum junction temperature rating.
(Note 1) When mounted (on 70 mm x 70 mm x 1.6 mm thick, glass epoxy on single-layer substrate) De-rated by 12 mW/°C when operating above Ta = 25 °C
Thermal Loss
The thermal design should be set operation for the following conditions.
1. The ambient temperature Ta must be 105 °C or less.
2. The IC’s loss must be within the allowable dissipation Pd.
The thermal dissipation characteristics are as follows.
(PCB: 70 mm x 70 mm x 1.6 mm, mounted on glass epoxy substrate)
Figure 13. Thermal Abatement Characteristics
Recommended Operating Conditions
Parameter
Symbol
Min
Typ
Max
Unit
Conditions
Operating Power Supply Voltage Range 1
VCC
15.0
24.0
27.5
V
VCC pin voltage
Operating Power Supply Voltage Range 2
VDRAIN
-0.3
-
+1700
V
DRAIN pin voltage
Operating Temperature
Topr
-40
25
+105
°C
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BM2SCQ12xT-LBZ Series
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TSZ22111 • 15 • 001
Electrical Characteristics
(Unless otherwise noted, VCC = 24 V, Ta = 25 °C)
Parameter
Symbol
Min
Typ
Max
Unit
Conditions
[MOSFET]
Voltage between DRAIN and SOURCE Pin
V(BR)DDS
1700
-
-
V
ID = 1 mA/VGS = 0 V
DRAIN Leak Current
IDSS
-
-
100
µA
VDS = 1700 V/VGS = 0 V
On Resistance
RDS(ON)
-
1.12
-
Ω
ID = 0.25 A/VGS = 18 V
[Operating Current]
Standby Operating Current
IOFF
10
19
30
µA
VCC = 18.0 V
(VCC UVLO = Disable)
Normal Operating Current
ION1
1000
2000
4000
µA
FB Pin Voltage= 1.0 V
(At Pulse Operation)
Burst Operating Current
ION2
150
500
1000
µA
FB Pin Voltage = 0.0 V
(At Burst Operation)
Protection Circuit Operating Current
IPROTECT
800
1600
2200
µA
FB OLP, VCC OVP,
ZT OVP
[VCC Pin Protection Function]
VCC UVLO Voltage 1
VUVLO1
19.00
19.50
20.00
V
VCC pin voltage rising
VCC UVLO Voltage 2
VUVLO2
13.00
14.00
15.00
V
VCC pin voltage falling
VCC UVLO Hysteresis Voltage
VUVLO3
-
5.50
-
V
VUVLO3 = VUVLO1 - VUVLO2
VCC OVP Voltage 1
VOVP1
27.50
29.50
31.50
V
VCC pin voltage rising
VCC OVP Voltage 2
VOVP2
21.00
23.00
25.00
V
VCC pin voltage falling
VCC OVP Hysteresis Voltage
VOVP3
-
6.50
-
V
VOVP3 = VOVP1 - VOVP2
Latch Released Voltage
VLATCH
-
VUVLO2-3.5
-
V
VCC pin Voltage
Latch Mask Time
tLATCH
50
150
250
µs
[DC/DC Converter Block (Turn OFF)]
FB Pin Pull-up Resistance
RFB
15
20
25
kΩ
SOURCE Pin
Over Current Detection Voltage 1A
VLIM1A
0.950
1.000
1.050
V
FB pin voltage = 2.2 V
(IZT ≥ -1.0 mA)
SOURCE Pin
Over Current Detection Voltage 1B
VLIM1B
0.620
0.700
0.780
V
FB pin voltage = 2.2 V
(IZT < -1.0 mA)
SOURCE Pin
Over Current Detection Voltage 2A
VLIM2A
0.200
0.300
0.400
V
FB pin voltage = 0.6 V
(IZT ≥ -1.0 mA)
SOURCE Pin
Over Current Detection Voltage 2B
VLIM2B
0.140
0.210
0.280
V
FB pin voltage = 0.6 V
(IZT < -1.0 mA)
SOURCE Pin Switching
ZT Pin Current
IZT
0.900
1.000
1.100
mA
SOURCE Pin
Leading Edge Blanking Time
tLEB
-
250
-
ns
Minimum ON Width
tMIN
-
0.500
-
µs
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TSZ22111 • 15 • 001
Electrical Characteristics – continued
(Unless otherwise noted, VCC = 24 V, Ta = 25 °C)
Parameter
Symbol
Min
Typ
Max
Unit
Conditions
[DC/DC Converter Block (Turn ON)]
Maximum Operating Frequency 1
fSW1
106
120
134
kHz
FB pin voltage = 2.0 V
Maximum Operating Frequency 2
fSW2
20
30
40
kHz
FB pin voltage = 0.5 V
FB Pin Frequency Reduction Start Voltage
VFBSW1
1.100
1.250
1.400
V
FB Pin Frequency Reduction End Voltage 1
VFBSW2
0.400
0.500
0.600
V
FB Pin Frequency Reduction End Voltage 2
VFBSW3
-
0.550
-
V
Voltage Gain
AV
1.700
2.000
2.300
V/V
ΔVFB/ΔVSOURCE
ZT Pin Comparator Voltage 1
VZT1
60
100
140
mV
ZT pin voltage falling
ZT Pin Comparator Voltage 2
VZT2
120
200
280
mV
ZT pin voltage rising
ZT Pin Trigger Mask Time
tZTMASK
0.25
0.60
0.95
µs
For noise prevention
after OUT pin voltage
H→L
ZT Pin Trigger Timeout Period 1
tZTOUT1
30.0
45.0
90.0
µs
Count from final ZT pin
trigger
ZT Pin Trigger Timeout Period 2
tZTOUT2
2.0
5.0
8.0
µs
Count from final ZT pin
trigger (2 stages)
Maximum ON Time
tZTON
27.0
45.0
62.0
µs
[DC/DC Protection Functions]
Soft Start Time 1
tSS1
0.600
1.000
1.400
ms
Soft Start Time 2
tSS2
2.400
4.000
5.600
ms
FB OLP Voltage 1
VFOLP1
2.500
2.800
3.100
V
FB pin voltage rising
FB OLP Voltage 2
VFOLP2
2.300
2.600
2.900
V
FB pin voltage falling
FB OLP Timer
tFOLP
90
128
166
ms
ZT OVP Voltage
VZTL
3.250
3.500
3.750
V
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TSZ22111 • 15 • 001
Typical Performance Curves
(Reference Data)
Figure 14. Standby Operating Current vs Temperature Figure 15. Normal Operating Current vs Temperature
Figure 16. Burst Operating Current vs Temperature Figure 17. Protection Circuit Operating Current vs Temperature
10.00
15.00
20.00
25.00
30.00
-40 -20 0 20 40 60 80 100 120
Standby Operating Current: IOFF [uA]
Temperature []
1500
1700
1900
2100
2300
2500
-40 -20 0 20 40 60 80 100 120
Normal Operating Current: ION1 [uA]
Temperature []
150
300
450
600
750
900
-40 -20 0 20 40 60 80 100 120
Burst Operating Current: ION2 [uA]
Temperature []
1000
1200
1400
1600
1800
2000
-40 -20 0 20 40 60 80 100 120
Protection Circuit
Operating Current: IPROTECT [uA]
Temperature []
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BM2SCQ12xT-LBZ Series
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TSZ22111 • 15 • 001
Typical Performance Curves – continued
(Reference Data)
Figure 18. VCC UVLO Voltage 1 vs Temperature Figure 19. VCC UVLO Voltage 2 vs Temperature
Figure 20. VCC UVLO Hysteresis Voltage vs Temperature Figure 21. VCC OVP Voltage 1 vs Temperature
19.0
19.2
19.4
19.6
19.8
20.0
-40 -20 0 20 40 60 80 100 120
VCC UVLO Voltage 1: VUVLO1 [V]
Temperature []
13.0
13.5
14.0
14.5
15.0
-40 -20 0 20 40 60 80 100 120
VCC UVLO Voltage 2: VUVLO2 [V]
Temperature []
4.5
5.0
5.5
6.0
6.5
-40 -20 0 20 40 60 80 100 120
VCC UVLO Hysteresis Voltage:
VUVLO3 [V]
Temperature []
27.5
28.5
29.5
30.5
31.5
-40 -20 0 20 40 60 80 100 120
VCC OVP Voltage 1: VOVP1 [V]
Temperature []
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TSZ22111 • 15 • 001
Typical Performance Curves – continued
(Reference Data)
Figure 22. FB Pin Pull-up Resistance vs Temperature Figure 23. SOURCE Pin Over Current Detection Voltage 1A
vs Temperature
Figure 24. SOURCE Pin Over Current Detection Voltage 1B Figure 25. SOURCE Pin Over Current Detection Voltage 2A
vs Temperature vs Temperature
15.0
17.0
19.0
21.0
23.0
25.0
-40 -20 0 20 40 60 80 100 120
FB Pin Pull-up Resistance: RFB[kΩ]
Temperature []
0.95
0.97
0.99
1.01
1.03
1.05
-40 -20 0 20 40 60 80 100 120
SOURCE Pin Over Current
Detection Voltage 1A: VLIM1A [V]
Temperature []
0.60
0.65
0.70
0.75
0.80
-40 -20 0 20 40 60 80 100 120
SOURCE Pin Over Current
Detection Voltage 1B: VLIM1B [V]
Temperature []
0.20
0.25
0.30
0.35
0.40
-40 -20 0 20 40 60 80 100 120
SOURCE Pin Over Current
Detection Voltage 2A: VLIM2A [V]
Temperature []
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TSZ02201-0F1F0A200470-1-2
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TSZ22111 • 15 • 001
Typical Performance Curves – continued
(Reference Data)
Figure 26 SOURCE Pin Over Current Detection Voltage 2B Figure 27. SOURCE Pin Switching ZT Pin Current
vs Temperature vs Temperature
Figure 28. Minimum ON Width vs Temperature Figure 29. Maximum Operating Frequency 1 vs Temperature
0.15
0.20
0.25
0.30
-40 -20 0 20 40 60 80 100 120
SOURCE Pin Over Current
Detection Voltage 2B: VLIM2B [V]
Temperature []
0.90
0.95
1.00
1.05
1.10
-40 -20 0 20 40 60 80 100 120
SOURCE Pin Switching
ZT Pin Current: IZT [mA]
Temperature []
0.10
0.20
0.30
0.40
0.50
0.60
0.70
0.80
0.90
-40 -20 0 20 40 60 80 100 120
Minimum ON Width: tMIN [μs]
Temperature []
110.0
115.0
120.0
125.0
130.0
-40 -20 0 20 40 60 80 100 120
Maximum Operating Frequency 1:
fSW1[kHz]
Temperature []
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TSZ22111 • 15 • 001
Typical Performance Curves – continued
(Reference Data)
Figure 30. Maximum Operating Frequency 2 Figure 31. FB Pin Frequency Reduction Start Voltage
vs Temperature vs Temperature
Figure 32. FB Pin Frequency Reduction End Voltage 1 Figure 33 FB Pin Frequency Reduction End Voltage 2
vs Temperature vs Temperature
20.0
25.0
30.0
35.0
40.0
-40 -20 0 20 40 60 80 100 120
Maximum Operating Frequency 2:
fSW2 [kHz]
Temperature []
1.10
1.15
1.20
1.25
1.30
1.35
1.40
-40 -20 0 20 40 60 80 100 120
FB Pin Frequency Reduction
Start Voltage: VFBSW1 [V]
Temperature []
0.40
0.45
0.50
0.55
0.60
-40 -20 0 20 40 60 80 100 120
FB Pin Frequency Reduction
End Voltage 1: VFBSW2 [V]
Temperature []
0.45
0.50
0.55
0.60
0.65
-40 -20 0 20 40 60 80 100 120
FB Pin Frequency Reduction
End Voltage 2: VFBSW3 [V]
Temperature []
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TSZ02201-0F1F0A200470-1-2
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BM2SCQ12xT-LBZ Series
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TSZ22111 • 15 • 001
Typical Performance Curves – continued
(Reference Data)
Figure 34. Voltage Gain vs Temperature Figure 35. ZT Pin Comparator Voltage 1 vs Temperature
Figure 36. Maximum ON Time vs Temperature Figure 37. Soft Start Time 1 vs Temperature
1.70
1.80
1.90
2.00
2.10
2.20
2.30
-40 -20 0 20 40 60 80 100 120
Voltage Gain: AV [V/V]
Temperature []
60
80
100
120
140
-40 -20 0 20 40 60 80 100 120
ZT Pin Comparator Voltage 1:
VZT1 [mV]
Temperature []
30.00
35.00
40.00
45.00
50.00
55.00
60.00
-40 -20 0 20 40 60 80 100 120
Maximum ON Time: tZTON [μs]
Temperature []
0.6
0.8
1.0
1.2
1.4
-40 -20 0 20 40 60 80 100 120
Soft Start Time 1: tSS1 [ms]
Temperature []
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TSZ02201-0F1F0A200470-1-2
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BM2SCQ12xT-LBZ Series
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TSZ22111 • 15 • 001
Typical Performance Curves – continued
(Reference Data)
Figure 38. Soft Start Time 2 vs Temperature Figure 39. FB OLP Voltage 1 vs Temperature
Figure 40. FB OLP Voltage 2 vs Temperature Figure 41. FB OLP Timer vs Temperature
2.5
3.0
3.5
4.0
4.5
5.0
5.5
-40 -20 0 20 40 60 80 100 120
Soft Start Time 2: tSS2 [ms]
Temperature []
2.5
2.6
2.7
2.8
2.9
3.0
3.1
-40 -20 0 20 40 60 80 100 120
FB OLP Voltage 1: VFOLP1 [V]
Temperature []
2.3
2.4
2.5
2.6
2.7
2.8
2.9
-40 -20 0 20 40 60 80 100 120
FB OLP Voltage 2: VFOLP2 [V]
Temperature []
100.0
110.0
120.0
130.0
140.0
150.0
-40 -20 0 20 40 60 80 100 120
FB OLP Timer: tFOLP [ms]
Temperature []
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BM2SCQ12xT-LBZ Series
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TSZ22111 • 15 • 001
Typical Performance Curves – continued
(Reference Data)
Figure 42. ZT OVP Voltage vs Temperature
I/O Equivalence Circuit
3.2
3.3
3.4
3.5
3.6
3.7
3.8
-40 -20 0 20 40 60 80 100 120
ZT OVP Voltage: VZTL [V]
Temperature []
VCC
GND
VCC Internal Reg
ZT
DRAIN
SOURCE
Internal MOSFET
1 2 3 4 5 6DRAIN SOURCE FB GND ZT VCC
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TSZ22111 • 15 • 001
Operational Notes
1. Reverse Connection of Power Supply
Connecting the power supply in reverse polarity can damage the IC. Take precautions against reverse polarity when
connecting the power supply, such as mounting an external diode between the power supply and the IC’s power
supply pins.
2. Power Supply Lines
Design the PCB layout pattern to provide low impedance supply lines. Separate the ground and supply lines of the
digital and analog blocks to prevent noise in the ground and supply lines of the digital block from affecting the analog
block. Furthermore, connect a capacitor to ground at all power supply pins. Consider the effect of temperature and
aging on the capacitance value when using electrolytic capacitors.
3. Ground Voltage
Ensure that no pins are at a voltage below that of the ground pin at any time, even during transient condition.
4. Ground Wiring Pattern
When using both small-signal and large-current ground traces, the two ground traces should be routed separately but
connected to a single ground at the reference point of the application board to avoid fluctuations in the small-signal
ground caused by large currents. Also ensure that the ground traces of external components do not cause variations
on the ground voltage. The ground lines must be as short and thick as possible to reduce line impedance.
5. Recommended Operating Conditions
The function and operation of the IC are guaranteed within the range specified by the recommended operating
conditions. The characteristic values are guaranteed only under the conditions of each item specified by the electrical
characteristics.
6. Inrush Current
When power is first supplied to the IC, it is possible that the internal logic may be unstable and inrush current may flow
instantaneously due to the internal powering sequence and delays, especially if the IC has more than one power
supply. Therefore, give special consideration to power coupling capacitance, power wiring, width of ground wiring, and
routing of connections.
7. Testing on Application Boards
When testing the IC on an application board, connecting a capacitor directly to a low-impedance output pin may
subject the IC to stress. Always discharge capacitors completely after each process or step. The IC’s power supply
should always be turned off completely before connecting or removing it from the test setup during the inspection
process. To prevent damage from static discharge, ground the IC during assembly and use similar precautions during
transport and storage.
8. Inter-pin Short and Mounting Errors
Ensure that the direction and position are correct when mounting the IC on the PCB. Incorrect mounting may result in
damaging the IC. Avoid nearby pins being shorted to each other especially to ground, power supply and output pin.
Inter-pin shorts could be due to many reasons such as metal particles, water droplets (in very humid environment) and
unintentional solder bridge deposited in between pins during assembly to name a few.
9. Unused Input Pins
Input pins of an IC are often connected to the gate of a MOS transistor. The gate has extremely high impedance and
extremely low capacitance. If left unconnected, the electric field from the outside can easily charge it. The small
charge acquired in this way is enough to produce a significant effect on the conduction through the transistor and
cause unexpected operation of the IC. So unless otherwise specified, unused input pins should be connected to the
power supply or ground line.
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TSZ22111 • 15 • 001
Operational Notes – continued
10. Regarding the Input Pin of the IC
This IC contains P+ isolation and P substrate layers between adjacent elements in order to keep them isolated. P-N
junctions are formed at the intersection of the P layers with the N layers of other elements, creating a parasitic diode or
transistor. For example (refer to figure below):
When GND > Pin A and GND > Pin B, the P-N junction operates as a parasitic diode.
When GND > Pin B, the P-N junction operates as a parasitic transistor.
Parasitic diodes inevitably occur in the structure of the IC. The operation of parasitic diodes can result in mutual
interference among circuits, operational faults, or physical damage. Therefore, conditions that cause these diodes to
operate, such as applying a voltage lower than the GND voltage to an input pin (and thus to the P substrate) should be
avoided.
Figure 43. Example of IC Structure
11. Ceramic Capacitor
When using a ceramic capacitor, determine a capacitance value considering the change of capacitance with
temperature and the decrease in nominal capacitance due to DC bias and others.
12. Thermal Shutdown Circuit (TSD)
This IC has a built-in thermal shutdown circuit that prevents heat damage to the IC. Normal operation should always
be within the IC’s maximum junction temperature rating. If however the rating is exceeded for a continued period, the
junction temperature (Tj) will rise which will activate the TSD circuit that will turn OFF power output pins. The IC should
be powered down and turned ON again to resume normal operation because the TSD circuit keeps the outputs at the
OFF state even if the Tj falls below the TSD threshold.
Note that the TSD circuit operates in a situation that exceeds the absolute maximum ratings and therefore, under no
circumstances, should the TSD circuit be used in a set design or for any purpose other than protecting the IC from
heat damage.
13. Over Current Protection Circuit (OCP)
This IC incorporates an integrated overcurrent protection circuit that is activated when the load is shorted. This
protection circuit is effective in preventing damage due to sudden and unexpected incidents. However, the IC should
not be used in applications characterized by continuous operation or transitioning of the protection circuit.
N N
P+PN N
P+
P Substrate
GND
NP+N N
P+
NP
P Substrate
GND GND
Parasitic
Elements
Pin A
Pin A
Pin B Pin B
B C
EParasitic
Elements
GND
Parasitic
Elements
CB
E
Transistor (NPN)Resistor
N Region
close-by
Parasitic
Elements
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03.Apr.2019 Rev.002
BM2SCQ12xT-LBZ Series
www.rohm.com
TSZ22111 • 15 • 001
Ordering Information
B
M
2
S
C
Q
1
2
x
T
-
L
B
Z
(FB OLP) (VCC OVP)
1: Auto Restart Latch
2: Latch Latch
3: Auto Restart Auto Restart
4: Latch Auto Restart
Package
T: TO220-6M
Product Rank
LB: Industrial applications
Lineup
Product name
FB OLP
VCC OVP
BM2SCQ121T-LBZ
Auto Restart
Latch
BM2SCQ122T-LBZ
Latch
Latch
BM2SCQ123T-LBZ
Auto Restart
Auto Restart
BM2SCQ124T-LBZ
Latch
Auto Restart
Marking Diagram
Product name
Part Number Marking
BM2SCQ121T-LBZ
M2SCQ121
BM2SCQ122T-LBZ
M2SCQ122
BM2SCQ123T-LBZ
M2SCQ123
BM2SCQ124T-LBZ
M2SCQ124
TO220-6M (TOP VIEW)
Part Number Marking
LOT Number
Notice-PAA-E Rev.004
© 2015 ROHM Co., Ltd. All rights reserved.
Notice
Precaution on using ROHM Products
1. If you intend to use our Products in devices requiring extremely high reliability (such as medical equipment (Note 1),
aircraft/spacecraft, nuclear power controllers, etc.) and whose malfunction or failure may cause loss of human life,
bodily injury or serious damage to property (“Specific Applications”), please consult with the ROHM sales
representative in advance. Unless otherwise agreed in writing by ROHM in advance, ROHM shall not be in any way
responsible or liable for any damages, expenses or losses incurred by you or third parties arising from the use of any
ROHM’s Products for Specific Applications.
(Note1) Medical Equipment Classification of the Specific Applications
JAPAN
USA
EU
CHINA
CLASSⅢ
CLASSⅢ
CLASSⅡb
CLASSⅢ
CLASSⅣ
CLASSⅢ
2. ROHM designs and manufactures its Products subject to strict quality control system. However, semiconductor
products can fail or malfunction at a certain rate. Please be sure to implement, at your own responsibilities, adequate
safety measures including but not limited to fail-safe design against the physical injury, damage to any property, which
a failure or malfunction of our Products may cause. The following are examples of safety measures:
[a] Installation of protection circuits or other protective devices to improve system safety
[b] Installation of redundant circuits to reduce the impact of single or multiple circuit failure
3. Our Products are not designed under any special or extraordinary environments or conditions, as exemplified below.
Accordingly, ROHM shall not be in any way responsible or liable for any damages, expenses or losses arising from the
use of any ROHM’s Products under any special or extraordinary environments or conditions. If you intend to use our
Products under any special or extraordinary environments or conditions (as exemplified below), your independent
verification and confirmation of product performance, reliability, etc, prior to use, must be necessary:
[a] Use of our Products in any types of liquid, including water, oils, chemicals, and organic solvents
[b] Use of our Products outdoors or in places where the Products are exposed to direct sunlight or dust
[c] Use of our Products in places where the Products are exposed to sea wind or corrosive gases, including Cl2,
H2S, NH3, SO2, and NO2
[d] Use of our Products in places where the Products are exposed to static electricity or electromagnetic waves
[e] Use of our Products in proximity to heat-producing components, plastic cords, or other flammable items
[f] Sealing or coating our Products with resin or other coating materials
[g] Use of our Products without cleaning residue of flux (Exclude cases where no-clean type fluxes is used.
However, recommend sufficiently about the residue.); or Washing our Products by using water or water-soluble
cleaning agents for cleaning residue after soldering
[h] Use of the Products in places subject to dew condensation
4. The Products are not subject to radiation-proof design.
5. Please verify and confirm characteristics of the final or mounted products in using the Products.
6.In particular, if a transient load (a large amount of load applied in a short period of time, such as pulse, is applied,
confirmation of performance characteristics after on-board mounting is strongly recommended. Avoid applying power
exceeding normal rated power; exceeding the power rating under steady-state loading condition may negatively affect
product performance and reliability.
7.De-rate Power Dissipation depending on ambient temperature. When used in sealed area, confirm that it is the use in
the range that does not exceed the maximum junction temperature.
8.Confirm that operation temperature is within the specified range described in the product specification.
9.ROHM shall not be in any way responsible or liable for failure induced under deviant condition from what is defined in
this document.
Precaution for Mounting / Circuit board design
1. When a highly active halogenous (chlorine, bromine, etc.) flux is used, the residue of flux may negatively affect product
performance and reliability.
2. In principle, the reflow soldering method must be used on a surface-mount products, the flow soldering method must
be used on a through hole mount products. If the flow soldering method is preferred on a surface-mount products,
please consult with the ROHM representative in advance.
For details, please refer to ROHM Mounting specification
Notice-PAA-E Rev.004
© 2015 ROHM Co., Ltd. All rights reserved.
Precautions Regarding Application Examples and External Circuits
1. If change is made to the constant of an external circuit, please allow a sufficient margin considering variations of the
characteristics of the Products and external components, including transient characteristics, as well as static
characteristics.
2. You agree that application notes, reference designs, and associated data and information contained in this document
are presented only as guidance for Products use. Therefore, in case you use such information, you are solely
responsible for it and you must exercise your own independent verification and judgment in the use of such information
contained in this document. ROHM shall not be in any way responsible or liable for any damages, expenses or losses
incurred by you or third parties arising from the use of such information.
Precaution for Electrostatic
This Product is electrostatic sensitive product, which may be damaged due to electrostatic discharge. Please take proper
caution in your manufacturing process and storage so that voltage exceeding the Products maximum rating will not be
applied to Products. Please take special care under dry condition (e.g. Grounding of human body / equipment / solder iron,
isolation from charged objects, setting of Ionizer, friction prevention and temperature / humidity control).
Precaution for Storage / Transportation
1. Product performance and soldered connections may deteriorate if the Products are stored in the places where:
[a] the Products are exposed to sea winds or corrosive gases, including Cl2, H2S, NH3, SO2, and NO2
[b] the temperature or humidity exceeds those recommended by ROHM
[c] the Products are exposed to direct sunshine or condensation
[d] the Products are exposed to high Electrostatic
2. Even under ROHM recommended storage condition, solderability of products out of recommended storage time period
may be degraded. It is strongly recommended to confirm solderability before using Products of which storage time is
exceeding the recommended storage time period.
3. Store / transport cartons in the correct direction, which is indicated on a carton with a symbol. Otherwise bent leads
may occur due to excessive stress applied when dropping of a carton.
4. Use Products within the specified time after opening a humidity barrier bag. Baking is required before using Products of
which storage time is exceeding the recommended storage time period.
Precaution for Product Label
A two-dimensional barcode printed on ROHM Products label is for ROHM’s internal use only.
Precaution for Disposition
When disposing Products please dispose them properly using an authorized industry waste company.
Precaution for Foreign Exchange and Foreign Trade act
Since concerned goods might be fallen under listed items of export control prescribed by Foreign exchange and Foreign
trade act, please consult with ROHM in case of export.
Precaution Regarding Intellectual Property Rights
1. All information and data including but not limited to application example contained in this document is for reference
only. ROHM does not warrant that foregoing information or data will not infringe any intellectual property rights or any
other rights of any third party regarding such information or data.
2. ROHM shall not have any obligations where the claims, actions or demands arising from the combination of the
Products with other articles such as components, circuits, systems or external equipment (including software).
3. No license, expressly or implied, is granted hereby under any intellectual property rights or other rights of ROHM or any
third parties with respect to the Products or the information contained in this document. Provided, however, that ROHM
will not assert its intellectual property rights or other rights against you or your customers to the extent necessary to
manufacture or sell products containing the Products, subject to the terms and conditions herein.
Other Precaution
1. This document may not be reprinted or reproduced, in whole or in part, without prior written consent of ROHM.
2. The Products may not be disassembled, converted, modified, reproduced or otherwise changed without prior written
consent of ROHM.
3. In no event shall you use in any way whatsoever the Products and the related technical information contained in the
Products or this document for any military purposes, including but not limited to, the development of mass-destruction
weapons.
4. The proper names of companies or products described in this document are trademarks or registered trademarks of
ROHM, its affiliated companies or third parties.
DatasheetDatasheet
Notice – WE Rev.001
© 2015 ROHM Co., Ltd. All rights reserved.
General Precaution
1. Before you use our Products, you are requested to carefully read this document and fully understand its contents.
ROHM shall not be in any way responsible or liable for failure, malfunction or accident arising from the use of any
ROHM’s Products against warning, caution or note contained in this document.
2. All information contained in this document is current as of the issuing date and subject to change without any prior
notice. Before purchasing or using ROHM’s Products, please confirm the latest information with a ROHM sales
representative.
3. The information contained in this document is provided on an “as is” basis and ROHM does not warrant that all
information contained in this document is accurate and/or error-free. ROHM shall not be in any way responsible or
liable for an y damages, expenses or losses incurred b y you or third parties resulting from inaccuracy or errors of or
concerning such information.
