LTC1426 Datasheet | Linear Technology

LTC1426 Micropower Dual 6-Bit PWM DAC Features s s s DESCRIPTION The LTC®1426 is a dual micropower 6-bit PWM DAC featuring versatile PWM outputs and a flexible pushbutton patible digital interface. The DAC outputs provide a PWM signal that swings from 0V to VREF, allowing the fullscale output to be varied by adjusting the voltage at VREF. The PWM output frequency is typically 5k Hz, easing output filtering requirements. VCC supply current is typically 50µA and drops to 0.2µA in shutdown. The LTC1426 can be controlled using one of two interface modes: pushbutton and pulse. The LTC1426 automatically configures itself into the appropriate mode at startup by monitoring the state of the CLK pins. In pushbutton mode, the CLK pins can be directly connected to external pushbuttons to control the DAC output. In pulse mode, the CLK pins can be connected to CMOS patible logic. The DAC outputs initially power up at half scale and the contents of the internal DAC registers are retained in shutdown. The LTC1426 is available in 8-pin MSOP and SO packages. , LTC and LT are registered trademarks of Linear Technology Corporation. s s s s s s s Wide Supply Range: 2.7V ≤ VCC ≤ 5.5V Wide Reference Voltage Range: 0V to 5.5V Two Interface Modes: Pulse Mode (Increment Only) Pushbutton Mode (Increment/Decrement) Low Supply Current: 50µA 0.2µA Supply Current in Shutdown Available in 8-Pin MSOP and SO Packages DAC Contents Are Retained in Shutdown DACs Power-Up at Midrange Low Output Impedance: < 100Ω Output Frequency: 5k Hz Typ U APPLICATIONS s s s s s LCD Contrast and Backlight Brightness Control Power Supply Voltage Adjustment Battery Charger Voltage and Current Adjustment Ga As FET Bias Adjustment Trimmer Pot Elimination TYPICAL APPLICATION Pushbutton Adjustable CCFL/LCD Contrast Generator UP TO 6m A LAMP HIGH VOLTAGE ROYER 16 15 14 13 12 11 10 9 5V C9 2.2µF 8V TO 28V ICCFL = 0µA TO 50µA 1 2 3 4 C7 1µF 8 7 6 5 R5 20k 1% C4 0.1µF C8 0.68µF 5 6 CCFL PGND CCFL VSW ICCFL DIO CCFL...