L4955

5A ULDO线性稳压器系列 5A ULDO LINEAR REGULATORS FAMILY

DESCRIPTION

The is a family of monolithic ultra very low drop linear regulators designed to supply the most recent microprocessors.

The dropout voltage is only 0.75V Typ. at 5A, directly dependent on the output current conditions. Realized in BCDII technology, it has on board a charge pump to properly drive an N-channel power mos Transistor with 150mΩ of RDSON.

It operates from a 4.5V minimum supply, with a very low quiescent current irrespective of the load; a minimum of 22µF output capacitor is required for stability.

The on-chip trimming techniques improve the precision of the available output voltages to ±2%.

■ UP TO 5A OUTPUT CURRENT

■ ±2% PRECISE OUTPUT VOLTAGES

■ FAST TRANSIENT RESPONSE

■ 0.75V TYP. DROP OUT VOLTAGE AT 5A

■ OPERATING INPUT VOLTAGEFROM 4.5V

■ ADJUSTABLE VERSION:

   • VO = 1.26V

   • INHIBIT IQ = 120µA TYP.

   • POWER GOOD

   • PROGRAMMABLE CURRENT LIMIT

   • HEPTAWATT PACKAGE

■ FIXED VERSION:

   • 3.3V, 5.1V OUTPUTS

   • VERSAWATT PACKAGE

VERY LOW QUIESCENT CURRENT

SHORT CIRCUIT PROTECTION Foldback function

THERMAL SHUTDOWN

APPLICATIONS

■ PENTIUM AND POWER PC SUPPLIES

■ POST REGULATOR FOR SMPS

■ LOW COST SOLUTION FOR 5V TO 3.3V CONVERSION

■ LOW COST BATTERY CHARGER

■ CONSTANT CURRENT REGULATOR

■ SUITABLE FOR APPLICATION WITH STANDBY FEATURE