July 1996
Product Highlights
Low Cost Replacement for Discrete Switchers
• 20 to 50 fewer components - cuts cost, increases reliability
• Source-connected tab and Controlled MOSFET turn-on
reduce EMI and EMI filter costs
• Allows for a 50% smaller and lighter solution
• Cost competitive with linears above 5 W
Up to 90% Efficiency in Flyback Topology
• Built-in start-up and current limit reduce DC losses
• Low capacitance 700 V MOSFET cuts AC losses
• CMOS controller/gate driver consumes only 6 mW
• 70% maximum duty cycle minimizes conduction losses
Simplifies Design - Reduces Time to Market
• Supported by many reference design boards
• Integrated PWM Controller and 700 V MOSFET in a
industry standard three pin TO-220 package
• Only one external capacitor needed for compensation,
bypass and start-up/auto-restart functions
System Level Fault Protection Features
• Auto-restart and cycle by cycle current limiting functions
handle both primary and secondary faults
• On-chip latching thermal shutdown protects the entire
system against overload
Highly Versatile
• Implements Buck, Boost, Flyback or Forward topology
• Easily interfaces with both opto and primary feedback
• Supports continuous or discontinuous mode of operation
Description
The TOPSwitch family implements, with only three pins, all
functions necessary for an off-line switched mode control
system: high voltage N-channel power MOSFET with controlled
turn-on gate driver, voltage mode PWM controller with
integrated 100 kHz oscillator, high voltage start-up bias circuit,
bandgap derived reference, bias shunt regulator/error amplifier
for loop compensation and fault protection circuitry. Compared
to discrete MOSFET and controller or self oscillating (RCC)
switching converter solutions, a TOPSwitch integrated circuit
can reduce total cost, component count, size, weight and at the
same time increase efficiency and system reliability. These
®
PI-1703-112995
AC
IN
DRAIN
SOURCE
CONTROL
TOPSwitch
Figure 1. Typical Application.
TOP200-4/14
TOPSwitch
Family
Three-terminal Off-line PWM Switch
devices are intended for 100/110/230 VAC off-line Power
Supply applications in the 0 to 100 W (0 to 50 W universal)
range and 230/277 VAC off-line power factor correction (PFC)
applications in the 0 to 150 W range.
TOP200YAI* 0-25 W 0-12 W 0-25 W
TOP201YAI* 20-45 W 10-22 W 20-50 W
TOP202YAI* 30-60 W 15-30 W 30-75 W
TOP203YAI* 40-70 W 20-35 W 50-100 W
TOP214YAI* 50-85 W 25-42 W 60-125 W
TOP204YAI* 60-100 W 30-50 W 75-150 W
ORDER
PART
NUMBER
230 VAC or
110 VAC
w/Doubler
FLYBACK
85-265
VAC
PFC/
BOOST
230/277
VAC
OUTPUT POWER RANGE
TOPSwitch
SELECTION GUIDE
®
* Package Outline: Y03A