
STMicroelectronics
Description
The L5970AD is a step down monolithic power switching regulator with a switch current limit of 1.5A so it is able to deliver more than 1A DC current to the load depending on the application conditions.
The output voltage can be set from 1.235V to 35V. The device uses an internal P-Channel D-MOS transistor (with a typical RDSON of 200mΩ) as switching element to avoid the use of bootstrap capacitor and guarantee high efficiency.
An internal oscillator fixes the switching frequency at 500KHz to minimize the size of external components.
Having a minimum input voltage of 4.4V only, it is particularly suitable for 5V bus, available in all computer related applications. Pulse by pulse current limit with the internal frequency modulation offers an effective constant current short circuit protection.
General Features
■ 1.5A INTERNAL SWITCH
■ OPERATING INPUT VOLTAGE FROM 4.4V TO 36V
■ 3.3V / (±2%) REFERENCE VOLTAGE
■ OUTPUT VOLTAGE ADJUSTABLE FROM 1.235V TO 35V
■ LOW DROPOUT OPERATION: 100% DUTY CYCLE
■ 500KHz INTERNALLY FIXED FREQUENCY
■ VOLTAGE FEEDFORWARD
■ ZERO LOAD CURRENT OPERATION
■ INTERNAL CURRENT LIMITING
■ INHIBIT FOR ZERO CURRENT CONSUMPTION
■ SYNCHRONIZATION
■ PROTECTION AGAINST FEEDBACK DISCONNECTION
■ THERMAL SHUTDOWN
APPLICATIONS:
■ CONSUMER: STB, DVD, TV, VCR,CAR RADIO, LCD MONITORS
■ NETWORKING: XDSL, MODEMS,DC-DC MODULES
■ COMPUTER: PRINTERS, AUDIO/GRAPHIC CARDS, OPTICAL STORAGE, HARD DISK DRIVE
■ INDUSTRIAL: CHARGERS, CAR BATTERY DC-DC CONVERTERS