CAT32: White LED Driver
The CAT32 is a DC/DC step up converter that delivers a regulated output current. Operation at a constant switching frequency of 1.2MHz allows the device to be used with very small value external inductor and ceramic capacitors. The CAT32 is targeted to drive multiple white light-emitting diodes (LEDs) connected in series and provides the necessary regulated current to control the brightness and the color purity. An external resistor RSET controls the output current level. LED currents of up to 40mA can be supported over a wide range of input supply voltages from 2V to 7V, making the device ideal for battery-powered applications. A high voltage output stage allows up to 4 White LEDs to be driven in series. Series drive provides inherent current matching. LED dimming can be done by using a DC voltage, a logic signal, or a pulse width modulation (PWM) signal. The shutdown input pin allows the device to be placed in power-down mode with 'near zero' quiescent current. In addition to overcurrent limiting protection, the device also includes detection circuitry to ensure protection against open-circuit load fault conditions. The device is available in a low profile (1mm max height) 6-lead TSOT-23 package.
Features- Low quiescent ground current (0.5 mA typical)
- Power efficiency over 80%
- Compatible pinout with LT1932
- Adjustable output current (up to 40 mA)
- High frequency 1.2 MHz operation
- Input voltage operation down to 2.0 V
- Low resistance (0.5Ω) high voltage power switch
- Drives up to 4 White LEDs in series
- Shutdown current less than 1µA
- Load fault protection against open-circuits
- Low value external components
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Applications- Color LCD and keypad backlighting
| End Products- Mobile Phones
- Portable MP3 Players
- Digital Cameras
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Application Notes (1)
Package Drawings (1)
Data Sheets (1)
Order Information
| Product | Status | Compliance | Package | MSL* | Container | Budgetary Price/Unit |
|---|
| CAT32TDI-GT3 | Active | Pb-free
Halide free | TSOT-23-6 | 419AF | 1 | Tape and Reel | 3000 | $0.6 |
Specifications
| Product | Topology | VIN Min (V) | VIN Max (V) | VO Max (V) | IO Max (mA) | fSW Typ (kHz) |
|---|
| CAT32TDI-GT3 | Step-Up | 2 | 5.5 | 20 | 25 | 1200 |
