CAT3644 Series

LED Driver, 4-Channel

Catalog

LED Driver, 4-Channel

Part	Dimming	Package / Case	Voltage - Supply (Max)	Topology	Number of Outputs	Internal Switch(s)	Current - Output / Channel [custom]	Operating Temperature [Max]	Operating Temperature [Min]	Mounting Type	Supplier Device Package	Applications	Frequency [Min]	Frequency [Max]	Voltage - Output	Voltage - Supply (Min) [Min]	Type
ON Semiconductor CAT3644HV3-GT2	Multi-Step	16-WFQFN Exposed Pad	5.5 V	Switched Capacitor (Charge Pump)	4		25 mA	85 °C	-40 °C	Surface Mount	16-TQFN (3x3)	Backlight	1 MHz	1.3 MHz	7 V	2.5 V	DC DC Regulator

Catalog

LED Driver, 4-Channel

Key Features

• High efficiency 1.33x charge pump

• Quad-mode charge pump: 1x, 1.33x, 1.5x, 2x

• Drives up to 4 LEDs at 25 mA each

• 1-wire EZDim™ LED current programming

• Power efficiency up to 92%

• Low noise input ripple in all modes

• "Zero" current shutdown mode

• Soft start and current limiting

• Short circuit protection

• Thermal shutdown protection

Description

The CAT3644 is a high efficiency fractional charge pump that can drive up to four LEDs programmable by a one wire digital interface. The inclusion of a 1.33x fractional charge pump mode increases device efficiency by up to 10% over traditional 1.5x charge pumps with no added external capacitors. Low noise input ripple is achieved by operating at a constant switching frequency which allows the use of small external ceramic capacitors. The multi-fractional charge pump supports a wide range of input voltages from 2.5 V to 5.5 V. The EN/DIM logic input functions as a chip enable and a digital dimming interface for current setting of all LEDs. Six different current ratios are available via the interface.