AT9933 Datasheet, PDF (1/16 Pages) Supertex, Inc – Hysteretic Boost-Buck (cuk) LED Driver IC

AT9933
Hysteretic Boost-Buck (Ćuk) LED Driver IC
Features
• Constant Current LED Driver
• Steps Input Voltage Up or Down
• Low Electromagnetic Interference (EMI)
• Variable Frequency Operation
• Internal 75V Linear Regulator
• Input and Output Current Sensing
• Input Current Limit
• Enable and Pulse-width Modulation (PWM)
Dimming
• Ambient Temperature Rating of up to 125°C
Applications
• LED Lighting Applications
General Description
The AT9933 is a variable frequency PWM controller IC,
designed to control an LED lamp driver using a
low-noise boost-buck (Ćuk) topology. It uses
patent-pending Hysteretic Current-mode control to
regulate both the input and the output currents. This
enables superior input surge immunity without the
necessity for complex loop compensation. Input
current control enables current limiting during Startup,
Input Undervoltage and Output Overload conditions.
The AT9933 provides a low-frequency PWM dimming
input that can accept an external control signal with a
duty cycle of 0%–100% and a high dimming ratio.
This AT9933-based LED driver is ideal for LED lamps.
The part is rated for up to 125°C ambient temperatures.
Package Type
See Table 2-1 for pin information.
8-lead SOIC
(Top View)
VIN 1
8 REF
CS1 2
GND 3
GATE 4
7 CS2
6 VDD
5 PWMD
 2016 Microchip Technology Inc.
DS20005597A-page 1