1FEATURES

2? 6μA typ. Quiescent Current

? VOUT = 3.6V to 5.7V (max VO = 5.7V)

? Operates from a Single Lithium Ion Cell (2.3V

to 5.5V)

? 8 User-selectable Output Voltages via I2C

? High-speed 3.4 MHz I2C-compatible Interface

? Up to 1.0A Maximum Load Current Capability

? 4 Levels of Current Limiting

? Auto-mode Operation and Forced PWM

? 2.5 MHz Switching Drequency (typ.)

? ±2.5% DC Output Voltage Precision

? 1.0 μH Inductor (2520 Case Size)

? 4.7 μF Input and Output Capacitors (0603 case

size)

? PGOOD Signal

? True Shutdown Isolation

? Output Over-voltage Protection

? Internal Active Voltage Balancing for

Supercapacitors

? DSBGA 9-bump Package

– (1.58 mm x 1.62 mm x 0.35 mm)(0.5 mm

pitch)

APPLICATIONS

? Flash LED

? Mobile Phones

? WiMAX

? USB

? Audio Amplifier

DESCRIPTION

LM8850 is a step-up DC-DC converter optimized for

use with a supercapacitor to protect a battery from

power surges and enable new high power

applications in mobile device architectures. The

device creates an ideal rail from 3.6V to 5.7V

boosting from a single Li-Ion cell with an input voltage

range of 2.3V to 5.5V; Target VOUT must be at least

10% higher than VIN.

An I2C interface controlling multiple output voltage

settings, input current limits, and load currents up to

1A provides superior user flexibility. The LM8850

operates in Auto mode, where the converter is in

PFM mode at light loads and switches to PWM mode

at heavy loads. Hysteretic PFM extends the battery

life by reduction of the quiescent current to 6μA (typ.)

during light load and standby conditions.

Synchronous operation provides true shutdown

isolation and improves its efficiency at medium-to-full

load conditions.