Fairchild FAN6863L service manual

FAN6863 Highly Integrated Green-Mode PWM Controller

FAN6863 — Highly Integrated Green-Mode PWM Controller

May 2011

Features

 Low Standby Power: Under 0.1W  Low Startup Current: 8µA  Low Operating Current at Green Mode: 600µA  Peak-Current Mode Operation with Cycle-by-Cycle

Current Limiting

 PWM Frequency Continuously Decreasing with

Burst Mode at Light Loads

 V

Over-Voltage Protection (OVP)

DD

 Constant Output Power Limit (Full AC Input Range)  Internal Latch Circuit (FAN6863L) for OVP, OTP  SENSE Pin Short-Circuit Protection (SSCP)  Fixed PWM Frequency (65KHz) with Frequency

Hopping

 Feedback Open-Loop Protection: 60ms Delay  GATE Output Maximum Voltage Clamp: 13.5V  Soft-Start Time: 5ms  Soft Driving for EMI Improvement  Full Range Frequency Hopping  Internal OTP Sensor with Hysteresis  GATE Driving Capability: 400mA

Description

A highly integrated PWM controller, FAN6863 provides several features to enhance the performance of flyback converters. To minimize standby power consumption, a proprietary Green Mode provides off-time modulation to continuously decrease the switching frequency under light-load conditions. Under zero-load conditions, the power supply enters Burst Mode, which completely shuts off PWM output. Output restarts just before the supply voltage drops below the UVLO lower limit. Green Mode enables power supplies to meet international power conservation requirements.

The FAN6863 is designed for SMPS and integrates a frequency-hopping function that helps reduce EMI emission of a power supply with minimum line filters. The built-in synchronized slope compensation provides proprietary sawtooth compensation for constant output power limit over universal AC input range. The gate output is clamped at 13.5V to protect the external MOSFET from over-voltage damage.

Other protection functions include SENSE pin ShortCircuit Protection (SSCP), V (OVP), and Over-Temperature Protection (OTP). For OTP, an external NTC thermistor can be applied to sense the ambient temperature. When V is activated, an internal latch circuit latches off the controller. Protection types shown in Table 1.

Table 1. Protection Type

Over-Voltage Protection

DD

OVP or OTP

DD

Applications

General-purpose switched-mode power supplies and flyback power converters, including:

 Power Adapters  Open-Frame SMPS

Part

Number

FAN6863 Latch A/R Latch A/R

FAN6863L Latch Latch Latch A/R

FAN6863R A/R A/R A/R A/R

OVP OLP

OTP / OTP2

SSCP

 SMPS with Surge-Current Output, such as for

Printers, Scanners, Motor Drivers

Ordering Information

Part Number

FAN6863TY

FAN6863LTY

FAN6863RTY

Operating

Temperature Range

-40 to +105°C

Package Packing Method

6-Lead, SuperSOT™-6, JEDEC M0-193,

1.6mm Wide

Tape & Reel

Typical Application

FAN6863 — Highly Integrated Green-Mode PWM Controller

Figure 1. Typical Application

Block Diagram

Figure 2. Block Diagram

Marking Information

Pin Configuration

Figure 3. Top Mark

ABx: ABR: FAN6863TY

ABF: FAN6863RTY ABG: FAN6863LTY

TT: Wafer Lot Code

:

_ _ _: Week Code

Year Code

FAN6863 — Highly Integrated Green-Mode PWM Controller

Figure 4. Pin Configuration

Pin Definitions

Pin # Name Function Description

1 GND Ground Ground.

The FB pin provides the output voltage regulation signal. It provides feedback to

2 FB Feedback

3 RT

4 SENSE Current Sense

5 VDD Power Supply Power supply.

6 GATE Driver Output The totem-pole output driver for driving the power MOSFET.

Temperature

Detection

the internal PWM comparator, so the PWM comparator can control the duty cycle. This pin also provides over-current protection. Once V trigger level and last for a long time, the controller stops and restarts.

An external NTC thermistor is connected from this pin to GND pin. The impedance of the NTC decreases at high temperatures. Once the voltage of the RT pin drops below a threshold, PWM output is disabled.

This pin senses the voltage across a resistor. When the voltage reaches the internal threshold, PWM output is disabled and this activates over-current protection. This pin also provides current amplitude information for CurrentMode control.

is large than

FB

FAN6863 — Highly Integrated Green-Mode PWM Controller

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. All voltage values, except differential voltages, are given with respect to GND pin.

Symbol Parameter Min. Max. Unit

VDD Supply Voltage 30 V

VL Input Voltage to FB, SENSE, and RT Pins -0.3 7.0 V

ΘJA Thermal Resistance (Junction-to-Ambient) 247 °C/W

TJ Operating Junction Temperature -40 +125 °C

T

Storage Temperature Range -55 +150 °C

STG

TL Lead Temperature, Wave Soldering, 10 Seconds +260 °C

ESD

Human Body Model, JESD22-A114 5.5

Charge Device Model, JESD22-C101 1.5

kV

Recommended Operating Conditions

The Recommended Operating Conditions table defines the conditions for actual device operation. Recommended operating conditions are specified to ensure optimal performance to the datasheet specifications. Fairchild does not recommend exceeding them or designing to Absolute Maximum Ratings.

Symbol Parameter Min. Max. Unit

TA Operating Ambient Temperature -40 +105 °C

Electrical Characteristics

VDD = 15V and TA = 25°C, unless otherwise noted.

Symbol Parameter Condition Min. Typ. Max. Unit

VDD Section

V

Continuously Operating Voltage 20 V

DD-OP

V

Turn-On Threshold Voltage 15 16 17 V

DD-ON

V

Turn-Off Voltage 6.5 7.0 7.5 V

DD-OFF

V

Threshold Voltage for Latch-Off Release 3 4 5 V

DD-LH

I

Startup Current V

DD-ST

I

DD-OP1

I

DD-OP2

V

DD-OVP

t

D-VDDOVP

I

DD-LH

Operating Supply Current when PWM Operation

Operating Supply Current when FB< V

FB-ZDC

VDD Over-Voltage Protection

VDD OVP Debounce Time 50 µs

Latch-Off Holding Current

Feedback Input Section

AV Input-Voltage to Current-Sense Attenuation 1/4.0 1/3.5 1/3.0 V/V

ZFB Input Impedance 17 kΩ

V

FB Pin Open Voltage 5.2 5.4 5.6 V

FB-OPEN

Threshold Voltage for Open-Loop Protection 4.3 4.6 4.9 V

FB-OLP

t

Open-Loop Protection Delay

D-OLP

t

Secondary Short Circuit Protection Delay

D-SCP

t

Short-Circuit Protection On-Time Detection

ON-SCP

Current Sense Section

tPD Delay to Output 100 250 ns

t

Leading-Edge Blanking Time 200 250 ns

LEB

V

Flat Threshold Voltage for Current Limit Duty>55% 0.6 V

STHFL

V

Valley Threshold Voltage for Current Limit Duty = 0% 0.39 V

STHVA

t

SOFT-START

V

t

ON-SSCP

Period During Startup Time Startup Time 5 ms

Threshold Voltage for SENSE Short-Circuit

SSCP

t

SSCP

Protection

Detect SENSE On Time for SENSE ShortCircuit Protection

Debounce Time for SENSE Short-Circuit Protection

– 0.16V 8 15 µA

DD-ON

VDD = 20V, V

= 3V Gate Open

FB

V

= 15V,

DD

V

< V

FB

FB-ZDC

2 mA

600 µA

FAN6863L-Latch, FAN6863R-Auto

21.5 22.5 23.5 V

Restart

= 5V; FAN6863,

V

DD

FAN6863L Only

FB > V

FB-OLP,

tON < 2.5µs,

= -40 to +105°C

T

A

FB > V t

< 2.5µs,

ON

T

= -40 to +105°C

A

FB>V T

= -40 to +105°C

A

t

> 4.5µs,

ON

FB < V

= -40 to +105°C

T

A

FB-OLP

,

t

> 4.5µs,

ON

FB < V T

= -40 to +105°C

A

FB-OLP

,

70 80 µA

54 60 65 ms

6 7 8 ms

2.5 µs

110 mV

4.4 µs

100 µs

FAN6863 — Highly Integrated Green-Mode PWM Controller

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Fairchild FAN6863L service manual

Specifications and Main Features

Frequently Asked Questions

User Manual