Document
AS78XXA
1A 3-TERMINAL POSITIVE VOLTAGE REGULATOR
Description
The DIODES™ AS78XXA series are three-terminal positive voltage regulators designed for a wide variety of applications including local, on-card regulation.
The AS78XXA are complete with internal current limiting, thermal shutdown protection, and safe-area compensation which make them virtually immune from output overload. If adequate heat sinking is provided, these regulators can deliver output currents of up to 1A.
The AS78XXA are available in TO-252-2 (3), TO-252-2 (4), TO-252-2 (5), TO-220-3, TO-220-3 (2), and TO-220F-3 packages.
Applications
High-efficiency linear regulators Post regulation for switching supplies Microprocessor power supplies Motherboards
Features
Output Current up to 1A Fixed Output Voltages of 5V, 6V, 8V, 9V, 12V, 15V, and 18V Output Voltage Accuracy of ±4% over the Full Temperature
Range Internal Short-Circuit Current Limiting Internal Thermal Overload Protection Output Transistor Safe-area Protection Low Load Regulation Stable Performance in High Temperature TO-220-3, TO-220-3 (2) and TO-220F-3
Lead-Free Finish; RoHS Compliant (Notes 1 & 3) Lead-Free Packages: TO-252-2 (3), TO-252-2 (4), TO-252-2 (5)
Totally Lead-Free; RoHS Compliant (Notes 2 & 3) Available in “Green” Packages: TO-220-3, TO-220-3 (2) and TO-
220F-3 Lead-Free Finish; RoHS Compliant (Notes 1 & 3) Halogen and Antimony Free. “Green” Device (Note 4)
Lead-Free Packages, Available in “Green” Molding Compound: TO-252-2 (3), TO-252-2 (4), TO-252-2 (5) Totally Lead-Free & Fully RoHS Compliant (Notes 2 & 3) Halogen and Antimony Free. “Green” Device (Note 4)
For automotive applications requiring specific change control (i.e. parts qualified to AEC-Q100/101/104/200, PPAP capable, and manufactured in IATF 16949 certified facilities), please contact us or your local Diodes representative. https://www.diodes.com/quality/product-definitions/
Notes:
1. EU Directive 2002/95/EC (RoHS), 2011/65/EU (RoHS 2) & 2015/863/EU (RoHS 3) compliant. All applicable RoHS exemptions applied. 2. No purposely added lead. Fully EU Directive 2002/95/EC (RoHS), 2011/65/EU (RoHS 2) & 2015/863/EU (RoHS 3) compliant. 3. See https://www.diodes.com/quality/lead-free/ for more information about Diodes Incorporated’s definitions of Halogen- and Antimony-free, "Green" and
Lead-free. 4. Halogen- and Antimony-free "Green” products are defined as those which contain <900ppm bromine, <900ppm chlorine (<1500ppm total Br + Cl) and
<1000ppm antimony compounds.
AS78XXA
Document number: DS36562 Rev. 6 - 2
1 of 28 www.diodes.com
May 2022
© Diodes Incorporated
Pin Assignments
(Front View)
3 2 1
TO-220-3 (Option 1)
OUTPUT GND INPUT
AS78XXA
(Front View)
3 2 1
TO-220-3 (Option 2)
OUTPUT GND INPUT
(Front View)
(Front View)
3 2 1
TO-220-3 (Option 3)
OUTPUT GND INPUT
3 2 1
TO-220-3 (2)
OUTPUT GND INPUT
(Front View)
3 2 1
TO-220F-3
OUTPUT GND INPUT
(Top View)
3
OUTPUT
2
GND
1
INPUT
TO-252-2 (3) (Option 1)
(Top View)
3
OUTPUT
2
GND
1
INPUT
TO-252-2 (3) (Option 2) / TO252 (Type CJ)
(Top View)
3
OUTPUT
2
GND
1
INPUT
TO-252-2 (4)
(Top View)
3 2 1
OUTPUT GND INPUT
TO-252-2 (5)
AS78XXA
Document number: DS36562 Rev. 6 - 2
2 of 28 www.diodes.com
May 2022
© Diodes Incorporated
Typical Applications Circuit VIN
AS78XXA
1
3
INPUT OUTPUT
0.33F
GND 2
VOUT
0.1F
AS78XXA
Pin Descriptions
Pin Number 1 2 3
Pin Name INPUT GND
OUTPUT
Voltage Input Ground Voltage Output
Function
Functional Block Diagram
R1 Q1 Q2
Q3
Q6
R3
Q4 R4
R5
Q5
R2
R9
Q9
Q14
C1 Q18
R12
D1 Zener R16 Q21
R20
R17
Q10
Q11
Q7
R7
Q16
Q22 R18
Q8 R6
R14
R11 R15
Q13 Q15 C2
Q23 R19
Q19
Q12
Q17
Q20
R8
R10
R13
1 INPUT
Q24 R21
R23
R2 2
3 OUTPUT
2 GND
AS78XXA
Document number: DS36562 Rev. 6 - 2
3 of 28 www.diodes.com
May 2022
© Diodes Incorporated
AS78XXA
Absolute Maximum Ratings (Note 5)
Note:
Symbol
Parameter
Rating
Unit
VIN TLEAD
PD TJ TSTG
JA
Input Voltage Lead Temperature (Soldering, 10sec) Power Dissipation Operating Junction Temperature Storage Temperature Range
Thermal Resistance
36
+260
Internally Limited
+150
-65 to +150
TO-220-3/TO-220-3 (2)
60
TO-252-2 (3)/TO-252-2 100
(4)/TO-252-2 (5)
TO-220F-3
60
V °C W °C °C
°C/W
ESD
ESD (Human Body Model)
6000
V
ESD
ESD (Machine Model)
500
V
5. Stresses greater than those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated under “Recommended Operating Conditions” is not implied. Exposure to “Absolute Maximum Ratings” for extended periods may affect device reliability.
Recommended Operating Conditions
Symbol VIN TJ
Parameter
AS7805A
AS7806A
AS7808A
Input Voltage
AS7809A
AS7812A
AS7815A
AS7818A
Operating .