Features
•Integrated 600V half-bridge gate driver
•15.6V zener clamp on Vcc
•True micropower start up
•Tighter initial deadtime control
•Low temperature coefficient deadtime
•Shutdown feature (1/6th Vcc) on CT pin
•Increased undervoltage lockout Hysteresis (1V)
•Lower power level-shifting circuit
•Constant LO, HO pulse widths at startup
•Lower di/dt gate driver for better noise immunity
•Low side output in phase with RT
•Internal 50nsec (typ.) bootstrap diode (IR21531D)
•Excellent latch immunity on all inputs and outputs
•ESD protection on all leads
•Also available LEAD-FREE
Preliminary Data Sheet No. PD60131 revM
SELF-OSCILLATING HALF-BRIDGE DRIVER
Product Summary
VOFFSET 600V max.
Duty Cycle 50%
Tr/Tp80/40ns
Vclamp 15.6V
Deadtime (typ.) 0.6 µs
Typical Connections
IR21531(D)(S) & (PbF)
Description
The IR21531(D)(S) are an improved version of the
popular IR2155 and IR2151 gate driver ICs, and in-
corporates a high voltage half-bridge gate driver with a front end oscillator similar to the industry standard
CMOS 555 timer. The IR21531 provides more functionality and is easier to use than previous ICs. A shutdown
feature has been designed into the CT pin, so that both gate driver outputs can be disabled using a low voltage
control signal. In addition, the gate driver output pulse widths are the same once the rising undervoltage
lockout threshold on VCC has been reached, resulting in a more stable profile of frequency vs time at
startup. Noise immunity has been improved significantly, both by lowering the peak di/dt of the gate drivers,
and by increasing the undervoltage lockout hysteresis to 1V. Finally, special attention has been payed to
maximizing the latch immunity of the device, and providing comprehensive ESD protection on all pins.
IR21531(D)
IR21531(S)
VB
HO
VS
LO
VCC
RT
CT
COM
600V
MAX
Shutdown
VB
HO
VS
LO
VCC
RT
CT
COM
600V
MAX
Shutdown
www.irf.com 1
Packages
8 Lead PDIP 8 Lead SOIC
IR21531(D)(S) & (PbF)
2www.irf.com
Note 1: This IC contains a zener clamp structure between the chip VCC and COM which has a nominal breakdown
voltage of 15.6V. Please note that this supply pin should not be driven by a DC, low impedance power source
greater than the VCLAMP specified in the Electrical Characteristics section.
Note 2: Care should be taken to avoid output switching conditions where the VS node flies inductively below ground by
more than 5V.
Note 3: Enough current should be supplied to the VCC pin of the IC to keep the internal 15.6V zener diode clamping the
voltage at this pin.
Recommended Operating Conditions
For proper operation the device should be used within the recommended conditions.
Symbol Definition Min. Max. Units
VBS High side floating supply voltage VCC - 0.7 VCLAMP
VSSteady state high side floating supply offset voltage -3.0 (note 2) 600
VCC Supply voltage 10 VCLAMP
ICC Supply current (note 3) 5 mA
TJJunction temperature -40 125 °C
V
Absolute Maximum Ratings
Absolute maximum ratings indicate sustained limits beyond which damage to the device may occur. All voltage param-
eters are absolute voltages referenced to COM, all currents are defined positive into any lead. The thermal resistance and
power dissipation ratings are measured under board mounted and still air conditions.
Symbol Definition Min. Max. Units
VBHigh side floating supply voltage -0.3 625
VSHigh side floating supply offset voltage VB - 25 VB + 0.3
VHO High side floating output voltage VS - 0.3 VB + 0.3
VLO Low side output voltage -0.3 VCC + 0.3
VRT RT pin voltage -0.3 VCC + 0.3
VCT CT pin voltage -0.3 VCC + 0.3
ICC Supply current (note 1) — 25
IRT RT pin current -5 5
dVs/dt Allowable offset voltage slew rate -50 50 V/ns
PDMaximum power dissipation @ TA ≤ +25°C (8 Lead DIP) — 1.0
(8 Lead SOIC) — 0.625
RthJA Thermal resistance, junction to ambient (8 Lead DIP) — 125
(8 Lead SOIC) — 200
TJJunction temperature -55 150
TSStorage temperature -55 150 °C
TLLead temperature (soldering, 10 seconds) — 300
V
°C/W
W
mA
IR21531(D)(S) & (PbF)
www.irf.com 3
Symbol Component Min. Max. Units
RTTiming resistor value 10 — kΩ
CTCT pin capacitor value 330 — pF
Recommended Component Values
IR2153 RT vs Frequency
10
100
1000
10000
100000
1000000
10 100 1000 10000 100000 1000000
RT (ohms)
Frequency (Hz)
330pf
470pF
1nF
2.2nF
4.7nF
10nF
CT Values
IR21531 RT vs Frequency
IR21531(D)(S) & (PbF)
4www.irf.com
Floating Supply Characteristics
Electrical Characteristics
VBIAS (VCC, VBS) = 12V, CL = 1000 pF, CT = 1 nF and TA = 25°C unless otherwise specified. The VIN, VTH and IIN
parameters are referenced to COM. The VO and IO parameters are referenced to COM and are applicable to the
respective output leads: HO or LO.
Symbol Definition Min. Typ. Max. Units Test Conditions
VCCUV+ Rising VCC undervoltage lockout threshold 8.1 9.0 9.9
VCCUV- Falling VCC undervoltage lockout threshold 7.2 8.0 8.8
VCCUVH VCC undervoltage lockout Hysteresis 0.5 1.0 1.5
IQCCUV Micropower startup VCC supply current — 75 150 VCC ≤ VCCUV-
IQCC Quiescent VCC supply current — 500 950
VCLAMP VCC zener clamp voltage 14.4 15.6 16.8 V ICC = 5mA
Low Voltage Supply Characteristics
V
µA
Symbol Definition Min. Typ. Max. Units Test Conditions
fosc Oscillator frequency 19.4 20 20.6 RT = 36.9kΩ
94 100 106 RT = 7.43kΩ
d RT pin duty cycle 48 50 52 % fo < 100kHz
ICT CT pin current — 0.001 1.0 uA
ICTUV UV-mode CT pin pulldown current 0.30 0.70 1.2 mA VCC = 7V
VCT+ Upper CT ramp voltage threshold — 8.0 —
VCT- Lower CT ramp voltage threshold — 4.0 —
VCTSD CT voltage shutdown threshold 1.8 2.1 2.4
VRT+ High-level RT output voltage, VCC - VRT — 10 50 I
RT = 100µA
— 100 300 IRT = 1mA
VRT- Low-level RT output voltage — 10 50 I
RT = 100µA
— 100 300 IRT = 1mA
VRTUV UV-mode RT output voltage — 0 100 VCC ≤ VCCUV-
VRTSD SD-Mode RT output voltage, VCC - VRT — 10 50 I
RT = 100µA,
VCT = 0V
— 10 300 IRT = 1mA,
VCT = 0V
Oscillator I/O Characteristics
V
mV
Symbol Definition Min. Typ. Max. Units Test Conditions
IQBSUV Micropower startup VBS supply current — 0 10 VCC ≤ VCCUV-
IQBS Quiescent VBS supply current — 30 50
VBSMIN Minimum required VBS voltage for proper — 4.0 5.0 V VCC=VCCUV+ + 0.1V
functionality from RT to HO
ILK Offset supply leakage current — — 50 µAV
B = VS = 600V
VFBootstrap diode forward voltage (IR21531D) 0.5 — 1.0 V IF = 250mA
µA
kHz
IR21531(D)(S) & (PbF)
www.irf.com 5
Lead Assignments
8 Lead DIP 8 Lead SOIC
IR21531(D) IR21531S
NOTE: The IR21531D is offered in 8 lead DIP only.
Symbol Description
VCC Logic and internal gate drive supply voltage
RTOscillator timing resistor input
CTOscillator timing capacitor input
COM IC power and signal ground
LO Low side gate driver output
VSHigh voltage floating supply return
HO High side gate driver output
VBHigh side gate driver floating supply
Lead Definitions
Symbol Definition Min. Typ. Max. Units Test Conditions
VOH High level output voltage, VBIAS -VO— 0 100 IO = OA
VOL Low-level output voltage, VO — 0 100 IO = OA
VOL_UV UV-mode output voltage, VO — 0 100 IO = OA
VCC ≤ VCCUV-
tr Output rise time — 80 150
tf Output fall time — 45 100
tsd Shutdown propogation delay — 660 —
td Output deadtime (HO or LO) 0.35 0.60 0.85 µsec
Gate Driver Output Characteristics
mV
nsec
Electrical Characteristics (cont.)
IR21531(D)(S) & (PbF)
6www.irf.com
Functional Block Diagram for IR21531(S)
Functional Block Diagram for IR21531D
VB
PULSE
GEN
DELAY
HV
LEVEL
SHIFT
VCC
PULSE
FILTER
DEAD
TIME
LO
VS
COM
R
S
Q
15.6V
CT
RT
UV
DETECT
R
Q
S
Q
DEAD
TIME
HO
LOGIC
-
-
-
+
+
+
R
R
R/2
R/2
D1
NOTE: The D1 is a separate die.
VB
PULSE
GEN
DELAY
HV
LEVEL
SHIFT
VCC
PULSE
FILTER
DEAD
TIME
LO
VS
COM
R
S
Q
15.6V
CT
RT
UV
DETECT
R
Q
S
Q
DEAD
TIME
HO
LOGIC
-
-
-
+
+
+
R
R
R/2
R/2
IR21531(D)(S) & (PbF)
www.irf.com 7
8 Lead SOIC 01-0021 08
8 Lead PDIP 01-3003 01
IR21531(D)(S) & (PbF)
8www.irf.com
Figure 1. Input/Output Timing Diagram
Figure 3. Deadtime Waveform Definitions
LO
R
T
C
T
Vcc
Vccuv+
V
CLAMP
R
T
,C
T
1/3
2/3
HO
td
td
Figure 2. Switching Time Waveform Definitions
(HO)
(LO)
IR21531(D)(S) & (PbF)
www.irf.com 9
LEADFREE PART MARKING INFORMATION
ORDER INFORMATION
Lead Free Released
Non-Lead Free
Released
Part number
Date code
IRxxxxxx
YWW?
?XXXX
Pin 1
Identifier
IR logo
Lot Code
(Prod mode - 4 digit SPN code)
Assembly site code
Per SCOP 200-002
P
?MARKING CODE
Basic Part (Non-Lead Free)
8-Lead PDIP IR21531 order IR21531
8-Lead SOIC IR21531S order IR21531S
8-Lead PDIP IR21531D order IR21531D
Leadfree Part
8-Lead PDIP IR21531 order IR21531PbF
8-Lead SOIC IR21531S order IR21531SPbF
8-Lead PDIP IR21531D order IR21531DPbF
IR WORLD HEADQUARTERS: 233 Kansas St., El Segundo, California 90245 Tel: (310) 252-7105
This product has been qualified per industrial level
Data and specifications subject to change without notice. 9/20/2005
