AP1084
5A Low Dropout Positive Adjustable or Fixed-Mode Regulator
This datasheet contains new product information. Anachip Corp. reserves the rights to modify the product specification without notice. No liability is assumed as a result of the use of
this product. No rights under any patent accompany the sale of the product.
Rev.1.2 Jun.9, 2005
1/11
Features
• 1.4V maximum dropout at full load current
• Built-in thermal shutdown
• Output current limiting
• Adjustable output voltage or fixed 1.5V, 1.8V, 2.5V,
3.3V, 5.0V
• Fast transient response
• Good noise rejection
• Package: TO252, TO263, TO220, PDIP-8
Ordering Information
General Description
AP1084 is a low dropout positive adjustable or fixed-
mode regulator with minimum of 5.0A output current
capability. The product is specifically designed to
provide well-regulated supply for low voltage IC
applications such as high-speed bus termination and
low current 3.3V logic supply. AP1084 is also well
suited for other applications such as VGA cards.
AP1084 is guaranteed to have lower than 1.4V
dropout at full load current making it ideal to provide
well-regulated outputs of 1.25 to 3.3V with 4.7 to
12V input supply.
AP1084 X X X X
Low Dropout Regulator Package Vout
D : TO252-3L
K : TO263-3L
T : TO220-3L
N : PDIP-8L
Blank : Adj
15 = 1.5V
18 = 1.8V
25 = 2.5V
33 = 3.3V
50 = 5.0V
Packing
Blank : Tube
A : Taping
Lead Free
Blank : Normal
L : Lead Free Package
Block Diagram
3
Thermal
Shutdown 1
2 Vout
Adj
1.25V +
+
CURRENT
LIMIT
Vin
－
+
－
+
This Anachip version datasheet is replaced
with Diodes Inc. datasheet AP1084
This Anachip version datasheet is replaced
with Diodes Inc. datasheet AP1084
AP1084
5A Low Dropout Positive Adjustable or Fixed-Mode Regulator
Anachip Corp.
www.anachip.com.tw Rev.1.2 Jun.9, 2005
2/11
Connection Diagram
TO263
3
2
1
Vin
Vout
Adj (GND)
Tab is Vout
FRONT VIEW
TO252
3
2
1
Vin
Vout
Adj (GND)
Tab is Vout
FRONT VIEW
TO220
Tab is Vout
3Vin
2
1
Vout
Adj (GND)
FRONT VIEW
AP1084
7
5
4
3
2
1
6
Vout
Adj(GND)
Vin
TOP VIEW
Vout
8
Vout
Vout
Vout
Vout
PDIP-8
Pin Descriptions
Pin No.
Name I/O TO263/
252/220 PDIP-8 Function
Adj
(GND) I 1 1
Adjustable (Ground only for fixed mode)
A resistor divider from this pin to the Vout pin and ground sets the
output voltage. (Ground only for Fixed-Mode)
Vout O 2 2/3/5/6/
7/8
The output of the regulator. A minimum of 10uF (0.15Ω ≤ ESR ≤
20Ω) capacitor must be connected from this pin to ground to insure
stability.
Vin I 3 4
The input pin of regulator. Typically a large storage capacitor (0.15
Ω
≤ ESR ≤ 20Ω) is connected from this pin to ground to insure that th
e
input voltage does not sag below the minimum dropout voltag
e
during the load transient response. This pin must always be 1.4
V
(1.3V) higher than Vout in order for the device to regulate properly.
This Anachip version datasheet is replaced
with Diodes Inc. datasheet AP1084
This Anachip version datasheet is replaced
with Diodes Inc. datasheet AP1084
AP1084
5A Low Dropout Positive Adjustable or Fixed-Mode Regulator
Anachip Corp.
www.anachip.com.tw Rev.1.2 Jun.9, 2005
3/11
Absolute Maximum Ratings
Symbol Parameter Rating Unit
Vin DC Supply Voltage -0.3 to 12 V
PD Power Dissipation Internally Limited
TST Storage Temperature -65 to +150 oC
TOP Operating Junction Temperature Range 0 to +150 oC
Electrical Characteristics (Under Operating Conditions)
Sym. Parameter Conditions (Notes) Min. Typ. Max. Unit
VREF Reference Voltage Io=10mA, Tj=25oC, (Vin-Vout)=1.5V 1.225 1.250 1.275 V
AP1084-XXX IO=10mA, VOUT+1.5V<VIN<12V, TJ =25oC 0.2 %
AP1084-1.5 IOUT = 10mA, TJ = 25oC, 3V≦VIN≦12V 1.470 1.500 1.530 V
AP1084-1.8 IOUT = 10mA, TJ = 25oC, 3.3V≦VIN≦12V 1.764 1.800 1.836 V
AP1084-2.5 IOUT = 10mA, TJ = 25oC, 4V≦VIN≦12V 2.450 2.500 2.550 V
AP1084-3.3 IOUT = 10mA, TJ = 25oC, 4.8V≦VIN≦12V 3.235 3.300 3.365 V
Line
Regulation
AP1084-5.0 IOUT = 10mA, TJ = 25oC, 6.5V≦VIN≦12V 4.900 5.000 5.100 V
AP1084-Adj VIN=3.3V, 0mA<Io<5A, TJ =25oC
(Note 1,2) 1 %
AP1084-1.5 VIN=3V, 0mA<Io<5A, TJ =25oC
(Note 1,2) 12 15 mV
AP1084-1.8 VIN=3.3V, 0mA<Io<5A
TJ =25oC (Note 1,2) 15 18 mV
AP1084-2.5 VIN=4V, 0mA<Io<5A
TJ =25oC (Note 1,2) 20 25 mV
AP1084-3.3 VIN = 5V, 0mA<Io<5A , TJ=25oC (Note 1,2) 26 33 mV
Load
Regulation
AP1084-5.0 VIN = 8V, 0mA<Io<5A, TJ=25oC (Note 1,2) 40 50 mV
∆Vo Dropout Voltage Io=5.0A (∆Vout = 1% Vout) 1.3 1.4 V
Current Limit Vin-Vout=5V 5.1 A
Minimum Load
Current 5 10 mA
Temperature
Stability Io=10mA 0.5 %
Thermal Resistance
Junction-to-Ambient
(No heat sink ;No
air flow)
TO-252
TO-263
TO-220
98
83
83
θJA
Thermal Resistance
Junction-to-Ambient
PDIP-8: Control Circuitry/Power Transistor
(Note 3) 35
OC/W
θJC Thermal Resistance
Junction-to-Case
TO-252: Control Circuitry/Power Transistor
TO-263: Control Circuitry/Power Transistor
TO-220: Control Circuitry/Power Transistor
10
0.65/2.7
0.65/2.7
OC/W
Note 1: See thermal regulation specifications for changes in output voltage due to heating effects. Line and load regulation are measured
at a constant junction temperature by low duty cycle pulse testing. Load regulation is measured at the output lead = 1/18” from the
package.
Note 2: Line and load regulation are guaranteed up to the maximum power dissipation of 15W. Power dissipation is determined by the
difference between input and output and the output current. Guaranteed maximum power dissipation will not be available over the
full input/output range.
Note 3: Output is connected to the PCB cupper area 5.5mm*5.5mm separately. If you need large PD or lower Tc & Tj, please connect to
the large cupper area >> 5.5mm*5.5mm (like 10mm*10mm).
This Anachip version datasheet is replaced
with Diodes Inc. datasheet AP1084
This Anachip version datasheet is replaced
with Diodes Inc. datasheet AP1084
AP1084
5A Low Dropout Positive Adjustable or Fixed-Mode Regulator
Anachip Corp.
www.anachip.com.tw Rev.1.2 Jun.9, 2005
4/11
Typical Circuit
(1) TO263/252/220
5.0V to 3.3V Fixed Mode Regulator
C2
100uF
5V
3.3V/5A
Tab is Vout
Vin
Vout
GND
C1
100uF
Adjustable Regulator
R1
R2
C2
100uF
5V
2.5V/5A
Tab is Vout
Vin
Vout
Adj
C1
100uF
121
121
Ω
Ω
)
R1
R2
(1VREF
VO+∗=
Note:
(2) PDIP-8
C2
100uF
5V
3.3V/1A
Tab is Vout
Vin
Vout
GND
C1
100uF
5V/3.3V fixed output
R1
121
R2
121
C2
100uF
5V
2.5V/1A
Tab is Vout
C1
100uF
o
V
5V/2.5V Adj output
Vout
Vout
Vout
Vout
Vout
Vin
Vout
Adj
Vout
Vout
Vout
Vout
Vout
Ω
Ω
)
R1
R2
(1VREF
VO+∗=
Note:
This Anachip version datasheet is replaced
with Diodes Inc. datasheet AP1084
This Anachip version datasheet is replaced
with Diodes Inc. datasheet AP1084
AP1084
5A Low Dropout Positive Adjustable or Fixed-Mode Regulator
Anachip Corp.
www.anachip.com.tw Rev.1.2 Jun.9, 2005
5/11
Functional Description
Introduction
The AP1084 adjustable Low Dropout (LDO) regulator
is a 3 terminal device that can easily be programmed
with the addition of two external resistors to any
voltages within the range of 1.25V to Vin-1.4V. The
AP1084 only needs 1.4V differential between Vin and
Vout to maintain output regulation. In addition, the
output voltage tolerances are also extremely tight and
they include the transient response as part of the
specification. For example, Intel VRE specification
calls for a total of +/- 100mV including initial tolerance,
load regulation and 0 to 5.0A load step.
The AP1084 is specifically designed to meet the fast
current transient needs as well as providing an
accurate initial voltage, reducing the overall system
cost with the need for fewer output capacitors.
Output Voltage Setting
The AP1084 can be programmed to any voltages in
the range of 1.25V to Vin-1.4V with the addition of R1
and R2 external resistors according to the following
formula:
Vout = Vref (1+ R2/R1) +Iadj *R2 , where Vref = 1.25 typically, Iadj =
55uA typically R1&R2 as shown at below
AP1084
Vin Vout
Vref
Adj R1
R2
Iadj=55uA
The AP1084 keeps a constant 1.25V between the
output pin and the adjust pin. By placing a resistor R1
across these two pins a constant current flows through
R1, adding to the Iadj current and into the R2 resistor
producing a voltage equal to the (1.25/R1)*R2+Iadj*R2
which will be added to the 1.25V to set the output
voltage. This is summarized in the above equation.
Since the minimum load current requirement of the
AP1084 is 10mA, R1 is typically selected to be 121Ω
resistor so that it automatically satisfies the minimum
current requirement. Notice that since Iadj is typically
in the range of 55uA it only adds a small error to the
output voltage and should only be considered when a
very precise output voltage setting is required. For
example, in a typical 3.3V application where R1=121Ω
and R2=200Ω the error due to Iadj is only 0.3% of the
nominal set point.
Load Regulation
Since the AP1084 is only a 3 terminal device, it is not
possible to provide true remote sensing of the output
voltage at the load. The best load regulation is
achieved when the bottom side of R2 is connected to
the load and the top-side of R1 resistor is connected
directly to the case or the Vout pin of the regulator and
not to the load. It is important to note that for high
current applications, this can re-present a significant
percentage of the overall load regulation and one must
keep the path from the regulator to the load as short
as possible to minimize this effect.
Stability
The AP1084 requires the use of an output capacitor as
part of the frequency compensation in order to make
the regulator stable. For most applications a minimum
of 10uF aluminum electrolytic capacitor insures both
stability and good transient response.
Thermal Design
The AP1084 incorporates an internal thermal
shutdown that protects the device when the junction
temperature exceeds the maximum allowable junction
temperature. Although this device can operate with
junction temperatures in the range of 150oC, it is
recommended that the selected heat sink be chosen
such that during maximum continuous load operation
the junction temperature is kept below the temperature.
Layout Consideration
The output capacitors must be located as close to the
Vout terminal of the device as possible. It is
recommended to use a section of a layer of the PC
board as a plane to connect the Vout pin to the output
capacitors to prevent any high frequency oscillation
that may result due to excessive trace inductance.
This Anachip version datasheet is replaced
with Diodes Inc. datasheet AP1084
This Anachip version datasheet is replaced
with Diodes Inc. datasheet AP1084
AP1084
5A Low Dropout Positive Adjustable or Fixed-Mode Regulator
Anachip Corp.
www.anachip.com.tw Rev.1.2 Jun.9, 2005
6/11
Performance Characteristics
Temperature (
o
C)
Percent Change in Output Voltage vs Temperature
Output Voltage Change (%)
-50 -25 0 25 50 75 100 125 150
- 2
-1.5
- 1
-0.5
0
0. 5
1
1.5
2
Input Voltage (V)
Line Regulation
Output Voltage Deviation (%)
0
0.2
0.4
0.6
0.8
1
24
6 8 10 12
TIME (us)
Line Transient Response
Output Voltage Deviation (mV) Input Voltage (V)
-40
-20
0
20
40
5.5
6.5
7.5 Cin=1uF
Cout=10uF Tantalum
0 20 40 60 80 100 120 140 160 180 200
TIME (us)
Load Transient Response
Load Current (A) Output Voltage Deviation (mV)
010
20 30 40 50 60 70 80 90 100
0
2
4
6
-40
-20
0
20
40
60 Cin=1uF
Cout=10uF Tantalum
Preload=100mA
Output Current (A)
Dropout Voltage vs Output Current
Dropout Voltage (V)
0
0. 2
0. 4
0. 6
0. 8
1. 0
1. 2
1. 4
1. 6
1. 8
2. 0
01234
Tj = 125
o
C
Tj = 25
o
C
5
Temperature (
o
C)
Load Regulation vs Temperature
Output Voltage Deviation (%)
-25 0 25 50 75 100 125
- 1
-0.80
-0.40
-0.20
0
0.20
I load=1.5A
This Anachip version datasheet is replaced
with Diodes Inc. datasheet AP1084
This Anachip version datasheet is replaced
with Diodes Inc. datasheet AP1084
AP1084
5A Low Dropout Positive Adjustable or Fixed-Mode Regulator
Anachip Corp.
www.anachip.com.tw Rev.1.2 Jun.9, 2005
7/11
Marking Information
Logo
Part Number
1084 for ADJ
84-VV : 15 for 1.5V
18 for 1.8V
25 for 2.5V
33 for 3.3V
50 for 5V
YY : Year
WW: Nth week
X : Internal code ( Optional)
( Top View)
84-VV
YYWWX X
Blank: normal
L: Lead Free Package
(TO252-3L)
Logo
Part Number
VV : 15 for 1.5V
18 for 1.8V
25 for 2.5V
33 for 3.3V
50 for 5V
Blank for ADJ
YY : Year
WW: Nth week
X : Internal code ( Optional)
( Top View)
1084-VV
YYWWX X Blank: normal
L: Lead Free Package
(TO220-3L / TO263-3L)
( Top View )
Logo
ID code: internal
Year: "01" =2001
"02" =2002
Xth week: 01~52
~
1
85
1084-VV
YY WW X X
4
Part Number
VV : 15 for 1.5V
18 for 1.8V
25 for 2.5V
33 for 3.3V
50 for 5V
Blank for ADJ
Blank: normal
L: Lead Free Package
(PDIP-8L)
This Anachip version datasheet is replaced
with Diodes Inc. datasheet AP1084
This Anachip version datasheet is replaced
with Diodes Inc. datasheet AP1084
AP1084
5A Low Dropout Positive Adjustable or Fixed-Mode Regulator
Anachip Corp.
www.anachip.com.tw Rev.1.2 Jun.9, 2005
8/11
Package Dimension
(1) TO263-3L
E
e
L2
b
b2
D
L3
L
A
C2
C
L1
1.3
3
15.7
10.9
9.1
Land Pattern Recommendation (Unit: mm)
2.54
Dimensions In Millimeters Dimensions In Inches
Symbol Min. Nom. Max. Min. Nom. Max.
A 4.06 4.45 4.83 0.160 0.175 0.190
b 0.51 0.75 0.99 0.020 0.030 0.039
b2 1.14 1.27 1.40 0.045 0.050 0.055
C 0.38 TYP. 0.015 TYP.
C2 1.14 1.27 1.40 0.045 0.050 0.055
D 8.65 9.15 9.65
0.341 0.360 0.380
E 9.65 9.97 10.29 0.380 0.393 0.405
e 2.54 BSC. 0.100 BSC.
L 14.61 15.24 15.88 0.575 0.600 0.625
L1 2.28 2.54 2.80
0.090 0.100 0.110
L2 - 1.30 2.92 - 0.051 0.115
L3 1.27 1.52 1.78 0.050 0.060 0.070
This Anachip version datasheet is replaced
with Diodes Inc. datasheet AP1084
This Anachip version datasheet is replaced
with Diodes Inc. datasheet AP1084
AP1084
5A Low Dropout Positive Adjustable or Fixed-Mode Regulator
Anachip Corp.
www.anachip.com.tw Rev.1.2 Jun.9, 2005
9/11
(2) TO252-3L
b2
E
e
b
L2
e1
DL1
H
A
C1
C
A1
SEATING PLANE
SEE NOTE2
L
5.6
11.0
5.6
2.0
2.25
Land Pattern Recommendation (Unit: mm)
7.2
1.2
Notes:
1. JEDEC Outline: TO-252 AB
2. Mils suggested for positive contact at mounting.
Dimensions In Millimeters Dimensions In Inches
Symbol Min. Nom. Max. Min. Nom. Max.
A 2.18 2.29 2.40 0.086 0.090 0.094
A1 0.89 - 1.14 0.035 - 0.045
b 0.61 TYP. 0.024 TYP.
b2 5.20 5.35 5.50 0.205 0.211 0.217
C 0.45 0.52 0.58 0.018 0.020 0.023
C1 0.45 0.52 0.58 0.018 0.020 0.023
D 5.40 5.57 6.20 0.213 0.219 0.244
E 6.35 6.58 6.80 0.250 0.259 0.268
e 2.28 BSC. 0.090 BSC.
e1 4.57 BSC. 0.180 BSC.
H 9.00 9.70 10.40 0.354 0.382 0.409
L 0.51 - - 0.020 - -
L1 0.64 0.83 1.02 0.025 0.033 0.040
L2 0.88 - 1.27 0.035 - 0.050
This Anachip version datasheet is replaced
with Diodes Inc. datasheet AP1084
This Anachip version datasheet is replaced
with Diodes Inc. datasheet AP1084
AP1084
5A Low Dropout Positive Adjustable or Fixed-Mode Regulator
Anachip Corp.
www.anachip.com.tw Rev.1.2 Jun.9, 2005
10/11
(3) TO220-3L
A
J1
F
C
SEATING PLANE
D
Q
E
L1
L
b
e
e1
b1
ΦP
H1
Dimensions In Millimeters Dimensions In Inches
Symbol Min. Nom. Max. Min. Nom. Max.
A 3.55 4.20 4.85 0.140 0.165 0.191
b1 1.14 1.46 1.78 0.045 0.057 0.070
b 0.51 0.83 1.14 0.020 0.033 0.045
C 0.31 0.72 1.14 0.012 0.028 0.045
D 14.20 15.35 16.50 0.559 0.604 0.650
E 9.70 10.20 10.70 0.382 0.402 0.421
e 2.29 2.54 2.79 0.090 0.100 0.110
e1 4.83 5.08 5.33 0.190 0.200 0.210
F 0.51 0.95 1.40 0.020 0.037 0.055
H1 5.84 6.35 6.86 0.230 0.250 0.270
J1 2.03 2.48 2.92 0.080 0.098 0.115
L 12.72 13.72 14.72 0.501 0.540 0.580
L1 3.66 5.00 6.35 0.144 0.197 0.250
øP 3.53 3.81 4.09 0.139 0.150 0.161
Q 2.54 2.98 3.43 0.100 0.117 0.135
This Anachip version datasheet is replaced
with Diodes Inc. datasheet AP1084
This Anachip version datasheet is replaced
with Diodes Inc. datasheet AP1084
AP1084
5A Low Dropout Positive Adjustable or Fixed-Mode Regulator
Anachip Corp.
www.anachip.com.tw Rev.1.2 Jun.9, 2005
11/11
(4) PDIP-8L
E1
D
7
(4X)
AL
A2A1
B2
B1
B
e
S
15 (4X)
E
C
eB
E-PIN O0.118 inch
PIN #1 INDENT O0.025 DEEP 0.006-0.008 inch
Dimensions in millimeters Dimensions in inches
Symbol Min. Nom. Max. Min. Nom. Max.
A - - 5.33 - - 0.210
A1 0.38 - - 0.015 - -
A2 3.1 3.30 3.5 0.122 0.130 0.138
B 0.36 0.46 0.56 0.014 0.018 0.022
B1 1.4 1.52 1.65 0.055 0.060 0.065
B2 0.81 0.99 1.14 0.032 0.039 0.045
C 0.20 0.25 0.36 0.008 0.010 0.014
D 9.02 9.27 9.53 0.355 0.365 0.375
E 7.62 7.94 8.26 0.300 0.313 0.325
E1 6.15 6.35 6.55 0.242 0.250 0.258
e - 2.54 - - 0.100 -
L 2.92 3.3 3.81 0.115 0.130 0.150
eB 8.38 8.89 9.70 0.330 0.350 0.382
S 0.71 0.84 0.97 0.028 0.033 0.038
This Anachip version datasheet is replaced
with Diodes Inc. datasheet AP1084
This Anachip version datasheet is replaced
with Diodes Inc. datasheet AP1084
