1 Features
1• Isolated Fly-Buck™ Topology
• Primary Side Feedback
• 100 kHz to 2000 kHz Switching Frequency
• Synchronizes to External Clock
• Adjustable Slow Start
• Adjustable Input Voltage UVLO
• Open Drain Fault Output
• Cycle-by-Cycle Current Limit
• Thermal Shutdown Protection
• 3 mm x 3 mm 16 Pin QFN Package

2 Applications
• Noise Immunity in PLCs, Data Acquisition and
Measurement Equipment
• Isolated RS-232 and RS-485 Communication
Channels
• Powers Line Drivers, ISO Amplifiers, Sensors,
CAN Transceivers
• Floating Supplies for IGBT Gate Drivers
• Promotes Safety in Medical Equipment

3 Description
The TPS55010 is a transformer driver designed to
provide isolated power for isolated interfaces, such as
RS-485 and RS-232, from 3.3 V or 5 V input supply.
The device uses fixed frequency current mode control
and half bridge power stage with primary side
feedback to regulate the output voltage for power
levels up to 2W. The switching frequency is
adjustable from 100 kHz to 2000 kHz so solution size,
efficiency and noise can be optimized. The switching
frequency is set with a resistor or is synchronized to
external clock using the RT/CLK pin. To minimize
inrush currents, a small capacitor can be connected
to the SS pin. The EN pin can be used as an enable
pin or to increase the default input UVLO voltage
from 2.6V.
With the same transformer the TPS55010 can
provide a solution for different input and output
voltage combinations by adjusting the primary side
voltage. Off the shelf transformers are available to
provide single positive, or dual positive and negative
output voltages.
The TPS55010 is available in a 3mm x 3mm 16 pin
QFN package with thermal pad.