Grenergy GR8837CG, GR8837JG Schematics

GR8837

Green-Mode PWM Controller with Latch Protection

Features

 Current mode control

 Standby power below 100mW

 Under-voltage lockout (UVLO)

 Non-audible-noise green-mode control

 65KHz switching frequency

 Internal leading-edge blanking

 Internal slope compensation

 Internal soft start

 Gate output voltage clamp

 Jitter and soft driving for reducing EMI

 External OVP Latch off mode

 External OTP Latch off mode

 Over-load protection (OLP)-Auto recovery

mode

 Vcc OVP protection- latch Mode

 300mA driving capability

Description

The GR8837 is a highly-integrated, low startup

current, current mode PWM controller with

green-mode function. The integrated functions also

include the leading-edge blanking of the current

sensing, internal slope compensation, soft start

OLP, and OCP. Besides, The RTL pin latch function

by injecting a high over 3.5V to provide OVP latch

off and low below 1V to provide OTP latch off

protection. These functions enable the power supply

to easily meet even the strictest power

requirements.

The GR8837 improves the performance and

reduces the cost of power supplies. It is with 8-pin

DIP and 6-pin SOT-26 package

Application

 Switching AC/DC Adapter

 Battery Charger

 Open frame SMPS

Ordering and Marking Information

DIP-8

Code 1 8 9 A B G H I J

Year 2008 2009 2010 2011

Code 2 1 2 3 4 9 A B C

Month Jan. Feb. Mar. Apr.

Grenergy OPTO Inc. reserves the right to make changes to improve reliability or manufacture ability without notice, and
advise customers to obtain the latest version of relevant information to verify before placing orders.

2016 2017 2018 2019

● ● ●

Sep. Oct. Nov. Dec.

SOT-26

2011.06 Ver.1.0.Copyright Grenergy OPTO, Inc. www.grenergy-ic.com

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Pin Configuration

Pin Description

Pin No. Name Function

1 GND Ground pin

2 COMP Voltage feedback pin, by connecting a photo-coupler to control the duty cycle

GND

COMP

RTL

1

2

3 4

6

5

OUT

VCC

CS

GR8837

3 RTL

4 CS Current sense pin, connect to sense the MOSFET current

5 VCC Power supply pin

6 OUT The output driver for driving the external MOSFET

Resistor trigger latch off which a high over 3.5V for OVP latch off and a low below

1V for OTP latch

Absolute Maximum Ratings

Supply voltage VCC --------------------------------------------------------------------------------------------------------- 30V

COMP, RTL, CS ---------------------------------------------------------------------------------------------------- -0.3 ~ 7V

OUT ----------------------------------------------------------------------------------------------------------- -0.3 ~ VCC + 0.3V

Junction temperature ------------------------------------------------------------------------------------------------------- 150℃

Operating ambient temperature ------------------------------------------------------------------------------ -20℃ ~ 85℃

Storage temperature range ---------------------------------------------------------------------------------- -65℃ ~ 150 ℃

SOT-26 package thermal resistance (junction to ambient) -------------------------------------------------- 250℃/W

Power dissipation (SOT-26, at ambient temperature = 85℃) ------------------------------------------------ 250mW

Power dissipation (DIP-8, at ambient temperature = 85℃) --------------------------------------------------- 650mW

Lead temperature (All Pb free packages, soldering, 10 sec) -------------------------------------------------- 260℃

ESD voltage protection, human body model -------------------------------------------------------------------------- 2KV

ESD voltage protection, machine model ------------------------------------------------------------------------------ 200V

2011.06 Ver.1.0.Copyright Grenergy OPTO, Inc. www.grenergy-ic.com

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Block Diagram

GR8837

2011.06 Ver.1.0.Copyright Grenergy OPTO, Inc. www.grenergy-ic.com

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GR8837

Electrical Characteristics (VCC = 15.0V & TA = +25℃,unless otherwise specified.)

Parameter Pin

SUPPLY VOLTAGE

Startup current (VCC=UVLO on - 1V) 5 8 15 uA

Operating current (with 1nF load on OUT pin), Vcomp = 0V 5 800 uA

Operating current (with 1nF load on OUT pin), Vcomp = 2.5V 5 1 2 3 mA

Min. Typ. Max. Unit

Operating current (with 1nF load on OUT pin), protection

tripped (OLP, OVP)

UVLO(off) 5 5.8 6.8 7.8 V

UVLO(on) 5 10.3 11.3 12.3 V

OVP level on VCC pin-latch Mode 5 27 28 29 V

VCC level in Latch mode (3Meg start-up resistor) 5 6 V

Holding current at latch mode (VCC=5V) 20 uA

Latch mode release voltage 5 3.2 V

VOLTAGE FEEDBACK

Short circuit current, Vcomp = 0V 2 0.8 mA

Open loop voltage, COMP pin open 2 4.4 5.5 V

Green-mode start voltage 2 1.5 V

Burst mode start voltage 2 0.85 V

CURRENT SENSING

Maximum input voltage, Vcs(off)-Auto recovery Mode 4 0.80 0.85 0.9 V

Leading-edge blanking time 4 350

Input impedance 4 1 MΩ

5 0.4 0.7 1 mA

nS

Delay to Output 4 100 nS

OSCILLATOR

Frequency - 60 65 70 KHz

Jitter frequency - +6 %

Green mode frequency - 22 KHz

Temp. stability (-40°C ~ 110°C)

Voltage stability (VCC = 11V~25V) - 3 %

GATE DRIVER OUTPUT

Output low level, VCC = 15V, Io = 20mA 6 1 V

Output high level, VCC = 15V, Io = 20mA 6

Rising time, load capacitance = 1000pF 6 200 nS

Falling time, load capacitance = 1000pF 6

VGATE-clamp (VCC = 25V ) 6 12 13 V

2011.06 Ver.1.0.Copyright Grenergy OPTO, Inc. www.grenergy-ic.com

- 5 %

8 V

80 nS

4

OLP SECTION

OLP trip level, Vcomp (OLP) - 3.5 V

OLP delay time - 60 mS

PWM SECTION

Maximum duty cycle - 70 75 80 %

RTL SECTION

Over Voltage Protection threshold voltage 3 3.2 3.5 3.8 V

OVP Debounce time 3 100 uS

Over Temperature Protection threshold voltage 3 0.95 1 1.05 V

OTP Debounce time 3 100 us

Output current from RTL pin 3 75 80 85 uA

RTL Pin voltage when floating 3 1.8 2.4 3.0 V

GR8837

2011.06 Ver.1.0.Copyright Grenergy OPTO, Inc. www.grenergy-ic.com

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