General Description

The MIC5321 is a tiny, dual ultra-low dropout linear

regulator ideally suited for applications that require high

PSRR because it provides a bypass pin for those noise

sensitive portable electronics. The MIC5321 integrates

two high-performance 150 mA ULDOs into a very

compact 1.6 mm x 1.6 mm leadless UDFN package

that provides exceptional thermal package

characteristics.

The MIC5321 is a μCap design that enables operation

with very small ceramic output capacitors for stability,

thereby reducing required board space and component

cost. The combination of extremely low dropout

voltage, very high power supply rejection, very low

output noise, and exceptional thermal package

characteristics makes it ideal for powering RF

application, cellular phone camera modules, imaging

sensors for digital still cameras, PDAs, MP3 players

and WebCam applications.

The MIC5321 is available in fixed-output voltages in the

tiny 6-pin 1.6 mm x 1.6 mm leadless UDFN package,

which is only 2.56 mm2 in area, less than 30 the area

of the SOT-23 and TSOP 3x3 packages. It’s also

available in the thin SOT-23 6-lead package and the

standard size 6-pin 1.6 mm x 1.6 mm leadless WDFN

package. Additional voltage options are available. For

more information, contact Microchip.

Features

• 2.3V to 5.5V Input Voltage Range

• Ultra-Low Dropout Voltage 35 mV @ 150 mA

• Tiny 6-Pin 1.6 mm x 1.6 mm Thin UDFN Leadless

Package

• Low Cost 6-Lead TSOT-23 Package

• Bypass Pin for Improved Noise Performance

• High PSRR: >75 dB on Each LDO

• Ultra-Low Noise Output: >30 μVRMS

• Dual 150 mA Outputs

• μCap Stable with 1 μF Ceramic Capacitor

• Low Quiescent Current: 150 μA

• Fast Turn-On Time: 45 μs

• Thermal Shutdown Protection

• Current Limit Protection

Applications

• Mobile Phones

• PDAs

• GPS Receivers

• Portable Electronics

• Portable Media Players

• Digital Still and Video Cameras