Fairchild FSQ100 service manual

FSQ100 Green Mode Fairchild Power Switch (FPS™)

FSQ100 — Green Mode Fairchild Power Switch (FPS

March 2011

Features

 Internal Avalanche-Rugged SenseFET  Precision Fixed Operating Frequency: 67KHz  Burst-Mode Operation  Internal Startup Circuit  Pulse-by-Pulse Current Limiting  Over-Voltage Protection (OVP)  Overload Protection (OLP)  Internal Thermal Shutdown Function (TSD)  Auto-Restart Mode  Under-Voltage Lockout (UVLO) with Hysteresis  Built-in Soft-Start  Secondary-Side Regulation

Applications

 Charger & Adapter for Mobile Phone, PDA, MP3  Auxiliary Power for White Goods, PC, C-TV, Monitor

Related Application Notes

Description

The FSQ100 consists of an integrated Pulse Width Modulator (PWM) and SenseFET, specifically designed for high-performance, off-line, Switch-Mode Power Supplies (SMPS) with minimal external components. This device is an integrated high-voltage power switching regulator that combines a VDMOS SenseFET with a voltage mode PWM control block. The integrated PWM controller features include a fixed oscillator, Under-Voltage Lockout (UVLO) protection, Leading Edge Blanking (LEB), an optimized gate turn-on/turn-off driver, Thermal Shutdown (TSD) protection, and temperature-compensated precision-current sources for loop compensation and fault protection circuitry.

When compared to a discrete MOSFET and controller or RCC solution, the FSQ100 device reduces total component count and design size and weight, while increasing efficiency, productivity, and system reliability. This device provides a basic platform well suited for cost-effective flyback converters.

TM

)

AN-4137 — Design Guidelines for Off-line Flyback



Converters using FPS™

 AN-4141 — Troubleshooting and Design Tips for

Fairchild Power Switch (FPS™) Flyback Applications

 AN-4147 — Design Guidelines for RCD Snubber of

Flyback

 AN-4134 — Design Guidelines for Off-line Forward

Converters using FPS™

 AN-4138 — Design Considerations for Battery

Charger Using Green Mode Fairchild Power Switch (FPS™)

Ordering Information

Product Number Package Marking Code BV

FSQ100 8-DIP Q100 650V 67KHz

FPS™ is a trademark of Fairchild Semiconductor Corporation.

f

DSS

R

OSC

DS(ON)

16Ω

A

f

A

r

Typical Application

FSQ100 — Green Mode Fairchild Power Switch (FPS

C

IN

V

STR

Drain

PWM

DC

OUT

V

FB

GND

CC

Figure 1. Typical Flyback Application

Table 1. Output Power Table

Product

230VAC ±15%

FSQ100 13W 8W

Notes:

1. Maximum practical continuous power in an open-frame design with sufficient drain pattern as a heat sinker, at 50C ambient.

2. 230VAC or 100/115VAC with doubler.

(2)

Open Frame

(1)

85~265V

AC

Internal Block Diagram

V

STR

V

2

CC

OSC

PWM

Internal

Bias

9/7V

Vck

SRQ

UVLO

I

delay

fb

µA

40

5

V

FB

3

0

Voltage

Re

L

H

5

DR IVER

D

6,7,8

ain

SFET

TM

)

S/ S

15ms

V

/

BURL

V

BURH

C

N

4

Reset

V

Min.20V

OV P

BURST

LEB

OLP

SD

TSD

SRQ

/R

I

LIM

R

V

th

sense

1

GND

Figure 2. Functional Block Diagram

r

Pin Assignments

FSQ100 — Green Mode Fairchild Power Switch (FPS

1

2

V

CC

V

3

FB

45

NC

Drain

8GND

ain

D

7

ain

6

D

V

STR

Figure 3. Pin Configuration (Top View)

Pin Definitions

Pin # Name Description

1 GND

2 VCC

3 VFB

4 NC

5 V

STR

6,7,8 Drain

Ground. SenseFET source terminal on primary-side and internal control ground. Positive Supply Voltage Input. Although connected to an auxiliary transformer winding,

current is supplied from pin 5 (V V

reaches the UVLO upper threshold (9V), the internal startup switch opens and device power

CC

) via an internal switch during startup (see Figure 2). When

STR

is supplied via the auxiliary transformer winding.

Feedback. Inverting input to the PWM comparator with its normal input level lies between 0.5V

and 2.5V. It has a 0.4mA current source connected internally, while a capacitor and optocoupler are typically connected externally. A feedback voltage of 4.5V triggers overload protection (OLP). There is a time delay while charging external capacitor C using an internal 5µA current source. This time delay prevents false triggering under transient conditions, but still allows the protection mechanism to operate in true overload conditions.

No Connection. Startup. This pin connects directly to the rectified AC line voltage source. At startup, the internal

switch supplies internal bias and charges an external storage capacitor placed between the VCC pin and ground. Once the V

reaches 9V, the internal switch stops charging the capacitor.

CC

SenseFET Drain. The drain pins are designed to connect directly to the primary lead of the

transformer and are capable of switching a maximum of 650V. Minimizing the length of the trace connecting these pins to the transformer decreases leakage inductance.

TM

)

from 3V to 4.5V

fb

FSQ100 — Green Mode Fairchild Power Switch (FPS

Absolute Maximum Ratings

Stresses exceeding the absolute maximum ratings may damage the device. The device may not function or be operable above the recommended operating conditions and stressing the parts to these levels is not recommended. In addition, extended exposure to stresses above the recommended operating conditions may affect device reliability. The absolute maximum ratings are stress ratings only. T

Symbol Parameter Value Unit

V

Drain Pin Voltage 650 V

DRAIN

V

VSTR Pin Voltage 650 V

STR

VDG Drain-Gate Voltage 650 V

VGS Gate-Source Voltage

VCC Supply Voltage 20 V

VFB Feedback Voltage Range -0.3 to V

PD Total Power Dissipation 1.40 W

TJ Operating Junction Temperature Internally limited °C

TA Operating Ambient Temperature -25 to +85 °C

T

Storage Temperature -55 to +150 °C

STG

Notes:

1. Repetitive rating: Pulse width is limited by maximum junction temperature.

2. L = 24mH, starting T

= 25C.

J

= 25°C, unless otherwise specified.

A

±20

STOP

V

TM

)

Thermal Impedance

TA = 25°C, unless otherwise specified. All items are tested with the JEDEC standards JESD 51-2 and 51-10 (DIP).

Symbol Parameter Value Unit

θJA Junction-to-Ambient Thermal Impedance

θJC Junction-to-Case Thermal Impedance

Notes:

3. Free-standing with no heatsink; without copper clad. Measurement condition; just before junction temperature TJ enters into OTP.

4. Measured on the DRAIN pin close to plastic interface.

(3)

88.84 °C/W

(4)

13.94 °C/W