STR-A6131 - Allegro MicroSystems, LLC

120 V/12 or 16 W

Flyback Switching Regulators

Data Sheet

28103.21*

STR-A6131 AND

STR-A6132

Sanken Power Devices

from Allegro MicroSystems

Switching

Regulators

ABSOLUTE MAXIMUM RATINGS

at TA = +25°C

Control Supply Voltage, VCC . . . . 35 V

Drain-Source Voltage, VDSS . . . . . . 500 V

Drain Switching Current, ID

STR-A6131 . . . . . . . . . . . . . . 3.2 A*

STR-A6132 . . . . . . . . . . . . . . 4.0 A*

Peak Drain Switching Current, IDM

STR-A6131 . . . . . . . . . . . . . . . 3.2 A

STR-A6132 . . . . . . . . . . . . . . . 4.0 A

Single-Pulse Avalanche Energy, EAS

STR-A6131 . . . . . . . . . . . . . . 32 mJ

STR-A6132 . . . . . . . . . . . . . . 78 mJ

Start-Up-Pin Voltage Range,

Vstartup . . . . . . . . . –0.3 V to +600 V

OCP Voltage Range,

VOCP . . . . . . . . . . . . –0.5 V to +6 V

FB/OLP Voltage Range,

VFB/OLP. . . . . . . . . . –0.5 V to +10 V

Package Power Dissipation, PD

control (VCC × ICC(ON)) . . . . . 0.15 W

MOSFET (VDSS × ID). . . . . . 1.35 W

total. . . . . . . . . . . . . . . . . . . . 1.5 W

MOSFET Channel Temp., TJ. +150°C

Internal Frame Temp., TF. . . . +125°C

Operating Temperature Range,

TA. . . . . . . . . . . -20°C to +125°C†

Storage Temperature Range,

TS. . . . . . . . . . . . -40°C to +125°C

* Drain switching current is limited by tem-

perature (page 2) and safe operating area

(page 4).

†For the availability of parts meeting -40°C

requirements, contact Allegro’s Sales Represen-

tative.

The STR-A6131 and STR-A6132 are PRC topology (fixed off-time)

regulators specifically designed to satisfy the requirements for increased

integration and reliability in flyback converters. They incorporate a

primary control and drive circuit with avalanche-rated power

MOSFETs. The STR-A6132 features higher switching current and

avalanche-energy ratings and lower on-resistance.

Covering the power range from below 12 watts to 16 watts for a 120

VAC input, these devices can be used in a range of applications, from

DVD and VCR players to ac adapters for cellular phones and digital

cameras. An auto-standby function reduces power consumption at light

load, while multiple protections, including the avalanche energy guaran-

teed MOSFET, provide high reliability of system design.

Cycle-by-cycle current limiting, undervoltage lockout with hyster-

esis, overvoltage protection, and thermal shutdown protect the power

supply during the normal overload and fault conditions. Overvoltage

protection and thermal shutdown are latched after a short delay. The

latch may be reset by cycling the input supply. Low start-up current and

a low-power standby mode selected from the secondary circuit completes

a comprehensive suite of features. Both devices are provided in an 8-pin

mini-DIP plastic package.

FEATURES AND BENEFITS

■Rugged 500 V Avalanche-Rated MOSFET

Simplified Surge Absorption

No VDSS Derating Required

■Choice of rDS(on) (2.62 Ω or 3.95 Ω maximum)

■Two Operational Modes by Automatic Switching:

PRC Mode for Normal Operation

Burst Mode for Stand-By Operation or Light Loads

■Built-In Leading Edge Blanking

■Low Start-Up Current

Start-Up Circuit Disabled in Operation

■Low Operating Current (1.5 mA typ)

■Automatic Burst Stand-By (intermittent operation)

Input Power <0.1 W at No Load — continued

Always order by complete part number, e.g., STR-A6131 .

STR-A6131 and STR-A6132

120 V/12 or 16 W

Flyback Switching Regulators

115 Northeast Cutoff, Box 15036

Worcester, Massachusetts 01615-0036

Switching

Regulators

FUNCTIONAL BLOCK DIAGRAM

FEATURES AND BENEFITS (cont’d)

■Auto-Bias Function

Stable Burst Operation Without Generating Interference

■Internal Off-Timer Circuit

■Built-In Constant-Voltage Drive

■Multiple Protections:

Pulse-by-Pulse Overcurrent Protection

Overload Protection with Auto Recovery

Latching Overvoltage Protection

Undervoltage Lockout with Hysteresis

Latching Thermal Shutdown

■Molded Small-Size 8-Pin Package

For Low-Height SMPS

Polarized to Prevent Backwards Assembly

STR-A6131 and STR-A6132

120 V/12 or 16 W

Flyback Switching Regulators

www.allegromicro.com

Switching

Regulators

ELECTRICAL CHARACTERISTICS at TA = 25°C, VCC = 20 V (unless otherwise specified).

Pin Ratings

Characteristic No. Symbol Test Conditions Min Typ Max Units

Drain-to-Source Breakdown Volt. 8 - 1 V(BR)DSS ID = 300 µA, 500 - - V

V1 – V3 = 0 V (short)

Drain Leakage Current 8 - 1 IDSS VDS = 500 V, - - 300 µA

V1 – V3 = 0 V (short)

On-State Resistance 8 - 1 rDS(on) STR-A6131, ID = 0.4 A - - 3.95 Ω

STR-A6132, ID = 0.4 A - - 2.62 Ω

MOSFET Switching Time 8 - 3 tf- - - 250 ns

Operation Start Voltage 2 - 3 VCC(ON) VCC = 0  19.2 V 16 17.5 19.2 V

Operation Stop Voltage 2 - 3 VCC(OFF) VCC = 19.2  9 V 9.0 10 11 V

Circuit Current in Operation 2 - 3 ICC(ON) - - - 4.0 mA

Circuit Current in Non-Operation 2 - 3 ICC(OFF) VCC = 14 V - - 50 µA

Auto-Bias Threshold Voltage 2 - 3 VCC(bias) VCC = 20  9.6 V 9.6 10.6 11.6 V

VCC(bias) - VCC(OFF) - - - 0.2 0.6 - V

Maximum OFF Time 8 - 3 tOFF - 7.3 8.0 8.7 µs

OCP Threshold Voltage 1 - 3 VOCP - 0.69 0.77 0.86 V

Leading Edge Blanking Time 8 - 3 tb- 200 320 480 ns

Burst Threshold Voltage 4 - 3 Vburst 0.70 0.79 0.88 V

OLP Threshold Voltage 4 - 3 VOLP - 6.5 7.2 7.9 V

Current at OLP Operation 4 - 3 IOLP - -18 -26 -35 µA

Maximum FB Current 4 - 3 IFB(MAX) - 227 300 388 µA

Start-Up Current 5 - 3 Istartup VCC = 15 V 340 790 1230 µ A

Start-Up Circuit Leakage Current 5 - 3 Istart(leak) ---30µA

OVP Operation Voltage 2 - 3 VCC(OVP) VCC = 0  34.1 V 28.7 31.2 34.1 V

OVP/TSD Latch Sustaining Current

2 - 3 ICC(H) VCC =34.1  8.5 V - - 200 µ A

OVP/TSD Latch Release Voltage 2 - 3 VCC VCC =34.1  6.6 V 6.6 7.3 8.0 V

Thermal Shutdown - TJ- 135 - - °C

Thermal Resistance - RθJF - - - 52 °C/W

WARNING — These devices are designed to be operated at lethal voltages and energy levels. Circuit designs

that embody these components must conform with applicable safety requirements. Precautions must

be taken to prevent accidental contact with power-line potentials. Do not connect grounded test

equipment.

The use of an isolation transformer is recommended during circuit development and breadboarding.

STR-A6131 and STR-A6132

120 V/12 or 16 W

Flyback Switching Regulators

115 Northeast Cutoff, Box 15036

Worcester, Massachusetts 01615-0036

Switching

Regulators

Avalanche energy is measured at VDD = 99 V,

L = 20 mH, IL = 2.1 A.

MOSFET TYPICAL CHARACTERISTICS

STR-A6132STR-A6131

Avalanche energy is measured at VDD = 99 V,

L = 20 mH, IL = 2.6 A.

STR-A6131 and STR-A6132

120 V/12 or 16 W

Flyback Switching Regulators

www.allegromicro.com

Switching

Regulators

MOSFET TYPICAL CHARACTERISTICS (cont’d)

STR-A6131

STR-A6132

STR-A6131 and STR-A6132

120 V/12 or 16 W

Flyback Switching Regulators

115 Northeast Cutoff, Box 15036

Worcester, Massachusetts 01615-0036

Switching

Regulators

Complete product description and applications information

is provided in Application Note 28103.20, Series STR-

A6100 Flyback Switching Regulators.

Typical Application

APPLICATIONS INFORMATION

The products described herein are manufactured in Japan by Sanken

Electric Co., Ltd. for sale by Allegro MicroSystems, Inc.

Sanken and Allegro reserve the right to make, from time to time, such

departures from the detail specifications as may be required to permit

improvements in the performance, reliability, or manufacturability of its

products. Therefore, the user is cautioned to verify that the information

in this publication is current before placing any order.

When using the pr oducts described her ein, the applicability and

suitability of such pr oducts for the intended purpose shall be r eviewed at

the users responsibility .

Although Sanken undertakes to enhance the quality and reliability of

its pr oducts, the occurr ence of failur e and defect of semiconductor

pr oducts at a certain rate is inevitable.

Users of Sanken pr oducts ar e r equested to take, at their own risk,

pr eventative measur es including safety design of the equipment or

systems against any possible injury , death, fir es or damages to society

due to device failure or malfunction.

Sanken pr oducts listed in this publication are designed and intended

for use as components in general-purpose electr onic equipment or

apparatus (home appliances, office equipment, telecommunication

equipment, measuring equipment, etc.). Their use in any application

r equiring radiation har dness assurance (e.g., aerospace equipment) is

not supported.

When considering the use of Sanken pr oducts in applications wher e

higher r eliability is r equired (transportation equipment and its contr ol

systems or equipment, fir e- or burglar-alarm systems, various safety

devices, etc.), contact a company sales r epresentative to discuss and

obtain written confirmation of your specifications.

The use of Sanken pr oducts without the written consent of Sanken in

applications wher e extremely high r eliability is requir ed (aer ospace

equipment, nuclear power-contr ol stations, life-support systems, etc.) is

strictly pr ohibited.

The information included herein is believed to be accurate and

reliable. Application and operation examples described in this publica-

tion are given for reference only and Sanken and Allegro assume no

responsibility for any infringement of industrial property rights,

intellectual property rights, or any other rights of Sanken or Allegro or

any third party that may result from its use.

STR-A6131 and STR-A6132

120 V/12 or 16 W

Flyback Switching Regulators

www.allegromicro.com

Switching

Regulators

PACKAGE DIMENSIONS

Dimensions in Millimeters

(controlling dimensions)

Product Weight: Approx. 0.51 g.

Frame temperature, TF, is measured at the root of pin 3.

Dimensions in Inches

(for reference only)

EI16EI