ELM600xB
1A 1.5MHz high efficiency synchronous PWM step down DC/DC converter

ELM600xB is a high efficiency step down DC/DC converter operated with current mode and constant frequency. The internal switch and synchronous rectifier are integrated for high efficiency. External Schottky diodes are not required. The supply current is only 100μA during operation and drops to less than 1μA in shutdown. ELM600xB can supply 1A of load current from 2.5V to 5.5V supply voltage. The switching frequency is set at 1.5MHz, allowing the use of small surface mount inductors and capacitors. It can run 100% duty cycle for low dropout application. The output voltage of ELM600xB is adjustable from the FB pin.

Current mode operation
Thermal shutdown protection
and short circuit protection
Constant frequencyTyp.1.5MHz
Output current1A
High efficiencyMax.95%
Shutdown currentMax.1µA
(Ven=0V, Vin=5.5V)
Supply voltage2.5V to 5.5V
Low quiescent currentTyp.110µA
(Outgoing stopped)
Full duty ratio0 to 100%
(in dropout)
PackageDFN6-2x2
TSOT-25
DatasheetELM600xB
Application
Cellular phone
PDA and smart phone
MP3 player
Digital camera
Wireless and DSL card
Microcomputer and DSP power supply
Portable machine

Absolute Maximum Ratings

ParameterSymbolLimitUnit
VIN power supply voltageVin-0.3 to +6.0V
Apply voltage to SWVswGND-0.3 to Vin+0.3V
Apply voltage to ENVenGND-0.3 to Vin+0.3V
Apply voltage to FBVfbGND-0.3 to Vin+0.3V
SW peak currentIsw3.0A
Power dissipationPd1000(DFN6-2x2)
600(TSOT-25)
mW
Operating temperature rangeTop-40 to +85°C
Storage temperature rangeTstg-65 to +150°C

Block diagram

block-diagram