Fairchild FSL126MRT service manual

FSL126MRT — Green-Mode Fairchild Power Switch (FPS™)

FSL126MRT Green-Mode Fairchild Power Switch (FPS™)

Features

 Internal Avalanched Rugged 650V SenseFET  Advanced Soft Burst-Mode Operation for Low

Standby Power and Low Audible Noise

 Random Frequency Fluctuation for Low EMI  Pulse-by-Pulse Current Limit  Various Protection Functions: Overload Protection

(OLP), Over-Voltage Protection (OVP), Abnormal Over-Current Protection (AOCP), Internal Thermal Shutdown (TSD) with Hysteresis and Under-Voltage Lockout (UVLO) with Hysteresis

 Low Operating Current(0.4mA) in Burst Mode  Internal Startup Circuit  Built-in Soft-Start: 15ms  Auto-Restart Mode

Description

The FSL126MRT is an integrated Pulse Width Modulation (PWM) controller and SenseFET specifically designed for offline Switch-Mode Power Supplies (SMPS) with minimal external components. The PWM controller includes an integrated fixed-frequency oscillator, Under-Voltage Lockout (UVLO), LeadingEdge Blanking (LEB), optimized gate driver, internal soft-start, temperature-compensated precise current sources for loop compensation, and self-protection circuitry. Compared with a discrete MOSFET and PWM controller solution, the FSL126MRT can reduce total cost, component count, size, and weight; while simultaneously increasing efficiency, productivity, and system reliability. This device provides a basic platform suited for cost-effective design of a flyback converter.

May 2012

Applications

 Power Supply for STB Home Appliances, and DVD

Combination

Ordering Information

(2)

(4)

Open

Frame

Replaces Device

(5)

Output Power Table

Part

Number

FSL126MRT

Notes:

1. Pb-free package per JEDEC J-STD-020B.

2. The junction temperature can limit the maximum output power.

3. 230V

4. Typical continuous power in a non-ventilated enclosed adapter measured at 50°C ambient temperature.

5. Maximum practical continuous power in an open-frame design at 50°C ambient temperature.

Package

TO-220F 6-Lead

W-Forming

or 100/115VAC with voltage doubler.

AC

Operating

Junction

Temperature

-40°C ~

(1)

+125°C

Current

Limit

1.2A

R

DS(ON)

(Max.)

6.2Ω

230VAC ± 15%

Adapter

(4)

30W 40W 17W 25W KA5M0265RYDTU

(3)

85~265VAC

Open

Frame

(5)

Adapter

Application Circuit

AC

IN

FSL126MRT — Green-Mode Fairchild Power Switch (FPS™)

V

O

V

STR

Drain

GND

Internal Block Diagram

V

burst

0.40V / 0.55V

FB

NC 5

V

4

CC

2.0µA I

DELAY

V

REF

90µA

I

FB

V

CC

Figure 1. Typical Application Circuit

V

STR

6 3

I

CH

3R

Soft-Start

R

Soft Burst

Random

OSC

PWM

V

SQ

R

LEB (350ns)

REF

Q

VCCGood

V

CC

Gate

Driver

Drain

1

7.5V / 12V

GND

2

V

SD

7.0V

V

CC

V

OVP

24.5V

TSD

VCCGood

SQ

R

Q

V

AOCP

Figure 2. Internal Block Diagram

Pin Configuration

FSL126MRT — Green-Mode Fairchild Power Switch (FPS™)

Figure 3. Pin Configuration (Top View)

Pin Definitions

Pin # Name Description

1 Drain

2 GND

3 VCC

4 FB

5 NC No Connection

6 V

SenseFET Drain. High-voltage power SenseFET drain connection. Ground. This pin is the control ground and the SenseFET source. Power Supply. This pin is the positive supply input, which provides the internal operating

current for both startup and steady-state operation. Feedback. This pin is internally connected to the inverting input of the PWM comparator.

The collector of an opto-coupler is typically tied to this pin. For stable operation, a capacitor should be placed between this pin and GND. If the voltage of this pin reaches 7V, the overload protection triggers, which shuts down the FPS.

Startup. This pin is connected directly, or through a resistor, to the high-voltage DC link. At startup, the internal high-voltage current source supplies internal bias and charges the

STR

external capacitor connected to the V source (I

) is disabled.

CH

pin. Once VCC reaches 12V, the internal current

CC

FSL126MRT — 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.

Symbol Parameter Min. Max. Unit

V

STR

V

Drain Pin Voltage 650 V

DS

V

CC

V

Feedback Pin Voltage -0.3 10.0 V

FB

I

Drain Current Pulsed

DM

I

Continuous Switching Drain Current 2 A

DS

EAS Single Pulsed Avalanche Energy

PD Total Power Dissipation (TC=25°C)

T

J

T

Storage Temperature -55 +150

STG

Notes:

6. Repetitive peak switching current when the inductive load is assumed: Limited by maximum duty (D

and junction temperature (see Figure 4).

7. L=45mH, starting TJ=25°C.

8. Infinite cooling condition (refer to the SEMI G30-88).

9. Although this parameter guarantees IC operation, it does not guarantee all electrical characteristics.

Pin Voltage 650 V

STR

Pin Voltage 26 V

CC

(6)

8 A

(7)

73 mJ

(8)

50 W

Maximum Junction Temperature 150

Operating Junction Temperature

(9)

-40 +125

MAX

°C

=0.74)

Figure 4. Repetitive Peak Switching Current

ESD Capability

Symbol Parameter Value Unit

ESD

Human Body Model, JESD22-A114 5

Charged Device Model, JESD22-C101 2

KV

Thermal Impedance

TA=25°C unless otherwise specified.

Symbol Parameter Value Unit

JA Junction-to-Ambient Thermal Impedance

JC Junction-to-Case Thermal Impedance

Notes:

10. Free standing without heat sink under natural convection condition, per JEDEC 51-2 and 1-10.

11. Infinite cooling condition per Mil Std. 883C method 1012.1.

(10)

63.5 °C/W

(11)

2.9 °C/W