Datasheet FSL138MRT Datasheet (Fairchild)

FSL138MRT — Green-Mode Fairchild Power Switch (FPS™) for High Input Voltage

FSL138MRT Green-Mode Fairchild Power Switch (FPS™) for High Input Voltage

Features

 Internal Avalanched-Rugged 800V SenseFET  Advanced Soft Burst-Mode Operation for

Low Standby Power and Low Audible Noise

 Under 40mW Standby Power Consumption

at 265V

 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

and No-load Condition

AC

Description

The FSL138MRT is an integrated Pulse Width Modulation (PWM) controller and SenseFET specifically designed for offline Switched-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 FSL138MRT 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

Industrial for High AC Input

Ordering Information

Operating

Part Number Package

TO-220F

FSL138MRT

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.

AC

6-Lead

W-Forming

or 100/115VAC with voltage doubler.

Junction

Temperature

-40°C ~ +125°C

(1)

Current

2.15A 5 35W 50W 24W 35W

Limit

R

DS(ON)

(Max.)

Adapter

Output Power Table

230VAC ± 15%

Open

(4)

Frame

(3)

85~265VAC

Adapter

(5)

(2)

(4)

Open

Frame

Replaces

Device

(5)

KA5M0380RY

DTU

Application Circuit

AC

IN

FSL138MRT — Green-Mode Fairchild Power Switch (FPS™) for High Input Voltage

V

O

V

STR

Drain

GND

Internal Block Diagram

V

BURST

0.30V / 0.45V

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

Pin Definitions

FSL138MRT — Green-Mode Fairchild Power Switch (FPS™) for High Input Voltage

Figure 3. Pin Configuration (Top View)

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

FSL138MRT — Green-Mode Fairchild Power Switch (FPS™) for High Input Voltage

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 800 V

DS

V

CC

V

FB

I

Drain Current Pulsed

DM

I

Continuous Switching Drain Current 3 A

DS

EAS Single Pulsed Avalanche Energy

PD

T

J

T

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=10mH, 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

Feedback Pin Voltage

(6)

12 A

Total Power Dissipation (T

=25°C)

C

Maximum Junction Temperature

Operating Junction Temperature

Storage Temperature

-0.3

(7)

134 mJ

(8)

45 W

150

(9)

-40

-55

10.0 V

+125

+150

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)

2.8 °C/W

FSL138MRT — Green-Mode Fairchild Power Switch (FPS™) for High Input Voltage

Electrical Characteristics

TJ=25°C unless otherwise specified.

Symbol Parameter Conditions Min. Typ. Max. Unit

SenseFET Section

BV

Drain-Source Breakdown Voltage

DSS

I

Zero-Gate-Voltage Drain Current

DSS

R

Drain-Source On-State Resistance VGS=10V, ID=1A 4.0 5.0 

DS(ON)

C

Input Capacitance

ISS

C

Output Capacitance

OSS

C

Reverse Transfer Capacitance

RSS

(12)

V

(12)

V

(12)

VDS=25V, VGS=0V, f=1MHz 5.1 pF

=0V, ID=250μA

V

CC

VDS=640V, TA=125°C

=25V, VGS=0V, f=1MHz 418 pF

DS

=25V, VGS=0V, f=1MHz 50.5 pF

DS

tr Rise Time VDS=400V, ID=3A, RG=25 29.2 ns

tf Fall Time VDS=400V, ID=3A, RG=25 24.6 ns

t

Turn-On Delay VDS=400V, ID=3A, RG=25 15.4 ns

d(on)

t

Turn-Off Delay VDS=400V, ID=3A, RG=25 23.7 ns

d(off)

Control Section

f

Switching Frequency

S

Δf

D

MAX

D

Switching Frequency Variation

S

Maximum Duty Ratio V

Minimum Duty Ratio V

MIN

(12)

V

(12)

=14V, VFB=4V 61 67 73 kHz

CC

-25°C < T

=14V, VFB=4V 61 67 73 %

CC

=14V, VFB=0V 0 %

CC

< 125°C

J

IFB Feedback Source Current VFB=0 65 90 115

V

START

V

STOP

t

S/S

UVLO Threshold Voltage

After Turn-on, V

Internal Soft-Start Time V

Burst-Mode Section

V

BURH

V

BURL

Burst-Mode Voltage VCC=14V, VFB Sweep

0.26 0.30 0.34 V

VFB=0V, V

Sweep 15 ms

CC

Sweep 11 12 13 V

CC

=0V 7.0 7.5 8.0 V

FB

Hys 150 mV

Protection Section

I

Peak Drain Current Limit

LIM

V

Shutdown Feedback Voltage V

SD

I

Shutdown Delay Current V

DELAY

t

Leading-Edge Blanking Time

LEB

V

Over-Voltage Protection VCC Sweep 23.0 24.5 26.0 V

OVP

T

SD

Hys Hysteresis 60

Thermal Shutdown Temperature

(12)(13)

di/dt=300mA/μs

=14V, V

CC

=14V, VFB=4V 1.2 2.0 2.8

CC

350 ns

Shutdown Temperature 130 140 150

(12)

Sweep 6.45 7.0 7.55 V

FB

800 V

250

μA

±5 ±10 %

μA

0.39 0.45 0.51 V

1.89 2.15 2.41 A

μA

°C

Continued on the following page…

FSL138MRT — Green-Mode Fairchild Power Switch (FPS™) for High Input Voltage

Electrical Characteristics (Continued)

TJ=25°C unless otherwise specified.

Symbol Parameter Conditions Min. Typ. Max. Unit

Total Device Section

I

OP

I

OPS

I

START

I

CH

V

STR

Operating Supply Current, (Control Part in Burst Mode)

Operating Switching Current, (Control Part and SenseFET Part)

Start Current

Startup Charging Current V

Minimum V

Supply Voltage VCC=VFB=0V, V

STR

V

=14V, VFB=0V 0.3 0.4 0.5 mA

CC

VCC=14V, VFB=2V 1.0 1.4 mA

=11V (Before VCC

V

CC

Reaches V

CC=VFB

START

=0V, V

)

=40V 0.7 1.0 1.3 mA

STR

Sweep 26 V

STR

85 120 155

Notes:

12. Although these parameters are guaranteed, they are not 100% tested in production.

13. t

includes gate turn-on time.

LEB

14. Average value.

Comparison of KA5M0380R and FSL138MRT

Function KA5M0380RYDTU FSL138MRT Advantages of FSL138MRT

Random Frequency

Fluctuation

Operating Current 7mA 0.4mA

High-Voltage Startup

Circuit

Protections

Power Balance Long t

N/A Built-in Low EMI

N/A Built-in

OLP OVP TSD

Very Short t

CLD

TSD with Hysteresis

OLP

OVP

AOCP

CLD

Very low standby power

Enhanced protections and high reliability

The difference of input power between the low and high input voltage is quite small

μA

Typical Performance Characteristics

Characteristic graphs are normalized at TA=25°C.

FSL138MRT — Green-Mode Fairchild Power Switch (FPS™) for High Input Voltage

1.40

1.30

1.20

1.10

1.00

0.90

Normalized

0.80

0.70

0.60

-40'C -20'C 0'C 25'C 50'C 75'C 9 0'C 110'C 120'C 125'C

Temperature [ °C]

1.40

1.30

1.20

1.10

1.00

0.90

Normalized

0.80

0.70

0.60

-40'C -20'C 0'C 25'C 50'C 75'C 90'C 110'C 120'C 125'C

Temperature [ °C]

Figure 5. Operating Supply Current (IOP) vs. TA Figure 6. Operating Switching Current (I

1.40

1.30

1.20

1.10

1.00

0.90

Normalized

0.80

0.70

0.60

-40'C -20'C 0'C 25'C 50'C 75'C 9 0'C 110'C 120'C 125'C

Temperature [ °C]

1.40

1.30

1.20

1.10

1.00

0.90

Normalized

0.80

0.70

0.60

-40'C -20'C 0'C 25 'C 50'C 75'C 90'C 110'C 120'C 125'C

Temperature [ °C]

OPS

) vs. TA

Figure 7. Startup Charging Current (ICH) vs. TA Figure 8. Peak Drain Current Limit (I

1.40

1.30

1.20

1.10

1.00

0.90

Normalized

0.80

0.70

0.60

-40'C -20'C 0'C 25'C 50'C 75'C 90'C 110'C 120'C 125'C

Temperature [ °C]

1.40

1.30

1.20

1.10

1.00

0.90

Normalized

0.80

0.70

0.60

-40'C -20'C 0'C 25 'C 50'C 75'C 90'C 110'C 120'C 125'C

Temperature [ °C]

Figure 9. Feedback Source Current (IFB) vs. TA Figure 10. Shutdown Delay Current (I

LIM

DELAY

) vs. TA

Typical Performance Characteristics

Characteristic graphs are normalized at TA=25°C.

FSL138MRT — Green-Mode Fairchild Power Switch (FPS™) for High Input Voltage

1.40

1.30

1.20

1.10

1.00

0.90

Normalized

0.80

0.70

0.60

-40'C -20'C 0'C 25'C 50'C 75'C 90'C 110'C 120'C 125'C

Temperature [ °C]

Figure 11. UVLO Threshold Voltage (V

1.40

1.30

1.20

1.10

1.00

0.90

Norm alized

0.80

0.70

0.60

-40'C -20'C 0'C 25'C 50'C 75'C 90'C 110'C 120'C 125'C

START

Temperature [ °C]

1.40

1.30

1.20

1.10

1.00

0.90

Norm alized

0.80

0.70

0.60

-40'C -20'C 0'C 25'C 50'C 75'C 90'C 110'C 120'C 125'C

Temperature [ °C]

) vs. TA Figure 12. UVLO Threshold Voltage (V

1.40

1.30

1.20

1.10

1.00

0.90

Normalized

0.80

0.70

0.60

-40'C -20'C 0'C 25'C 50'C 75'C 90'C 110'C 120'C 125'C

Temperature [ °C]

STOP

) vs. TA

Figure 13. Shutdown Feedback Voltage (VSD) vs. TA Figure 14. Over-Voltage Protection (V

1.40

1.30

1.20

1.10

1.00

0.90

Normalized

0.80

0.70

0.60

-40'C -20'C 0'C 25'C 50'C 75'C 90 'C 110'C 120'C 125'C

Temperature [ °C]

1.40

1.30

1.20

1.10

1.00

0.90

Normalized

0.80

0.70

0.60

-40'C -20'C 0'C 25'C 50'C 75'C 90'C 110'C 120'C 125'C

Temperature [ °C]

Figure 15. Switching Frequency (fS) vs. TA Figure 16. Maximum Duty Ratio (D

OVP

MAX

) vs. TA

Functional Description

1. Startup: At startup, an internal high-voltage current

source supplies the internal bias and charges the external capacitor (C illustrated in Figure 17. When V FSL138MRT begins switching and the internal highvoltage current source is disabled. Normal switching operation continues and the power is supplied from the auxiliary transformer winding unless V stop voltage of 7.5V.

V

CC

3 6

7.5V/12.0V

Figure 17. Startup Block

2. Soft-Start: The internal soft-start circuit increases

PWM comparator inverting input voltage, together with the SenseFET current, slowly after startup. The typical soft-start time is 15ms. The pulse width to the power switching device is progressively increased to establish the correct working conditions for the transformers, inductors, and capacitors. The voltage on the output capacitors is progressively increased to smoothly establish the required output voltage. This helps prevent transformer saturation and reduces stress on the secondary diode during startup.

) connected to the VCC pin, as

VCC

C

Vcc

VCCGood

reaches 12V, the

CC

goes below the

CC

V

DC

I

CH

V

REF

Internal

Bias

Drain

3. Feedback Control: This device employs CurrentMode control, as shown in Figure 18. An opto-coupler (such as the FOD817) and shunt regulator (such as the KA431) are typically used to implement the feedback network. Comparing the feedback voltage with the voltage across the R

resistor makes it possible to

SENSE

control the switching duty cycle. When the reference pin voltage of the shunt regulator exceeds the internal reference voltage of 2.5V, the opto-coupler LED current increases, pulling down the feedback voltage and reducing drain current. This typically occurs when the input voltage is increased or the output load is decreased.

3.1 Pulse-by-Pulse Current Limit: Because Current-Mode control is employed, the peak current through the SenseFET is limited by the inverting input of PWM comparator (V

*), as shown in

FB

Figure 18. Assuming that the 90A current source flows only through the internal resistor (3R + R =27k), the cathode voltage of diode D2 is about

2.4V. Since D1 is blocked when the feedback voltage (V

) exceeds 2.4V, the maximum voltage

FB

of the cathode of D2 is clamped at this voltage. Therefore, the peak value of the current through the SenseFET is limited.

3.2 Leading-Edge Blanking (LEB): At the instant the internal SenseFET is turned on, a high-current spike usually occurs through the SenseFET, caused by primary-side capacitance and secondary-side rectifier reverse recovery. Excessive voltage across the R

resistor leads

SENSE

to incorrect feedback operation in the Current-Mode PWM control. To counter this effect, the leadingedge blanking (LEB) circuit inhibits the PWM comparator for t

(350ns) after the SenseFET is

LEB

turned on.

FSL138MRT — Green-Mode Fairchild Power Switch (FPS™) for High Input Voltage

Figure 18. Pulse Width Modulation Circuit

4. Protection Circuits: The FSL138MRT has several self-protective functions, such as Overload Protection (OLP), Abnormal Over-Current Protection (AOCP), Over-Voltage Protection (OVP), and Thermal Shutdown (TSD). All the protections are implemented as autorestart. Once the fault condition is detected, switching is terminated and the SenseFET remains off. This causes V

to fall. When VB

CC

B falls to the Under-Voltage Lockout

CC

(UVLO) stop voltage of 7.5V, the protection is reset and the startup circuit charges the V

capacitor. When VCC

CC

reaches the start voltage of 12.0V, the FSL138MRT resumes normal operation. If the fault condition is not removed, the SenseFET remains off and V stop voltage again. In this manner, the auto-restart can alternately enable and disable the switching of the power SenseFET until the fault condition is eliminated. Because these protection circuits are fully integrated into the IC without external components, reliability is improved without increasing cost.

drops to

CC

Figure 20. Overload Protection

4.2 Abnormal Over-Current Protection (AOCP):

When the secondary rectifier diodes or the transformer pins are shorted, a steep current with extremely high di/dt can flow through the SenseFET during the minimum turn-on time. Even though the FSL138MRT has overload protection, it is not enough to protect the FSL138MRT in that abnormal case; due to the severe current stress imposed on the SenseFET until OLP is triggered. The internal AOCP circuit is shown in Figure 21. When the gate turn-on signal is applied to the power SenseFET, the AOCP block is enabled and monitors the current through the sensing resistor. The voltage across the resistor is compared with a preset AOCP level. If the sensing resistor voltage is greater than the AOCP level, the set signal is applied to the S-R latch, resulting in the shutdown of the SMPS.

Figure 19. Auto-Restart Protection Waveforms

4.1 Overload Protection (OLP): Overload is defined

as the load current exceeding its normal level due to an unexpected abnormal event. In this situation, the protection circuit should trigger to protect the SMPS. However, even when the SMPS is in normal operation, the overload protection circuit can be triggered during the load transition. To avoid this undesired operation, the overload protection circuit is designed to trigger only after a specified time to determine whether it is a transient situation or a true overload situation. Because of the pulse-by-pulse current limit capability, the maximum peak current through the SenseFET is limited and, therefore, the maximum input power is restricted with a given input voltage. If the output consumes more than this maximum power, the output voltage (V

) decreases

OUT

below the set voltage. This reduces the current

Figure 21. Abnormal Over-Current Protection

through the opto-coupler LED, which also reduces the opto-coupler transistor current, increasing the feedback voltage (V

). If VFB exceeds 2.4V, D1 is

FB

blocked and the 2.0µA current source starts to charge V

slowly up. In this condition, VFB continues

FB

increasing until it reaches 7.0V, when the switching operation is terminated, as shown in Figure 20. The delay for shutdown is the time required to charge CFB from 2.4V to 7.0V with 2.0µA. This protection is implemented in Auto-Restart Mode.

FSL138MRT — Green-Mode Fairchild Power Switch (FPS™) for High Input Voltage

4.4 Over-Voltage Protection (OVP): If the

secondary-side feedback circuit malfunctions or a solder defect causes an opening in the feedback path, the current through the opto-coupler transistor becomes almost zero. Then V

climbs up in a similar

FB

manner to the overload situation, forcing the preset maximum current to be supplied to the SMPS until the overload protection is triggered. Because more energy than required is provided to the output, the output voltage may exceed the rated voltage before the overload protection is triggered, resulting in the breakdown of the devices in the secondary side. To prevent this situation, an OVP circuit is employed. In general, the V and the FS136MRT uses V monitoring the output voltage. If V

is proportional to the output voltage

CC

instead of directly

CC

exceeds 24.5V,

CC

an OVP circuit is triggered, resulting in the termination of the switching operation. To avoid undesired activation of OVP during normal operation, V

should

CC

be designed to be below 24.5V.

4.5 Thermal Shutdown (TSD): The SenseFET and the control IC on a die in one package makes it easier for the control IC to detect the over temperature of the SenseFET. If the temperature exceeds 140°C, the thermal shutdown is triggered and stops operation. The FSL138MRT operates in Auto-Restart Mode until the temperature decreases to around 80°C, when normal operation resumes.

5. Soft Burst-Mode Operation: To minimize power dissipation in Standby Mode, the FSL138MRT enters Burst-Mode operation. As the load decreases, the feedback voltage decreases. The device automatically enters Burst Mode when the feedback voltage drops below V

(300mV), as shown in Figure 22. At this

BURL

point, switching stops and the output voltages start to drop at a rate dependent on standby current load. This causes the feedback voltage to rise. Once it passes V

(450mV), switching resumes. The feedback

BURH

voltage then falls and the process repeats. Burst Mode alternately enables and disables switching of the SenseFET, reducing switching loss in Standby Mode.

6. Random Frequency Fluctuation (RFF): Fluctuating switching frequency of an SMPS can reduce EMI by spreading the energy over a wide frequency range. The amount of EMI reduction is directly related to the switching frequency variation, which is limited internally. The switching frequency is determined randomly by external feedback voltage and an internal free-running oscillator at every switching instant. This random frequency fluctuation scatters the EMI noise around typical switching frequency (67kHz) effectively and can reduce the cost of the input filter included to meet the EMI requirements (e.g. EN55022).

Figure 23. Random Frequency Fluctuation

Figure 22. Burst-Mode Operation

Physical Dimensions

FSL138MRT — Green-Mode Fairchild Power Switch (FPS™) for High Input Voltage

16.07

15.67

8.13

7.13

3.40

3.20

1.40

1.20

(1.13)

2.19

10.16

9.96

(7.00)

2.74

2.34

3.28

Ø

3.08

(5.40)

6.90

(0.70)

6.50

20.00

19.00

(13.05)

24.00

23.00

(0.48)

R0.55

0.80

0.70

0.50

61

1,3,5 2,4,6

3.06

2.46

(7.15)

0.60

1.75

0.45

1.27

3.48

2.88

3.81

5°

Figure 24. TO-220F-6L (W-Forming)

NOTES: UNLESS OTHERWISE SPECIFIED

A) THIS PACKAGE DOES NOT COMPLY TO ANY CURRENT PACKAGING STANDARD. B) ALL DIMENSIONS ARE IN MILLIMETERS. C) DIMENSIONS ARE EXCLUSIVE OF BURRS, MOLD FLASH, AND TIE BAR EXTRUSIONS. D) LEADFORM OPTION A E) DFAWING FILENAME: TO220A06REV4

Package drawings are provided as a service to customers considering Fairchild components. Drawings may change in any manner without notice. Please note the revision and/or date on the drawing and contact a Fairchild Semiconductor representative to verify or obtain the most recent revision. Package specifications do not expand the terms of Fairchild’ s worldwide terms and conditions, specifically the warranty therein, which covers Fairchild products.

Always visit Fairchild Semiconductor’s online packaging area for the most recent package drawings:

http://www.fairchildsemi.com/packaging/

.

FSL138MRT — Green-Mode Fairchild Power Switch (FPS™) for High Input Voltage