high efficiency synchronous PWM step down DC/DC converter
■General
description
ELM600LA is high efficiency synchronous step down DC/DC converter operated with current mode and 1.4MHz
constant frequency; internal switch and synchronous rectifier are integrated for high efficiency. In application,
ELM600LA does not require any external Schottky diode. Internal current consumption under operation of
ELM600LA is as low as 200µA and drops to less than 1µA in shutdown mode. With supply voltage from 2.5V
to 6V, ELM600LA can supply load current of 800mA; the output voltage can be regulated as low as 0.6V.
With 1.4MHz switching frequency, ELM600LA makes it possible to adopt small surface amount inductors and
capacitors. Switch duty cycle would be on continuously and 100% at maximum when input voltage is set be to
lower than output voltage.
ELM600LA
800mA 1.4MHz
■Features
•
•
•
•
•
•
•
•
•
•
Current mode operation
Thermal shutdown protection and short circuit protection
Constant frequency
: Typ.1.4MHz
: 800mA
Output current
: Max.95%
High efficiency
: Max.1µA(Ven=0V, Vin=6V)
Shutdown current
Supply voltage
: 2.5V to 6V
Low quiescent current
: Typ.200µA
: 0 to 100% (in dropout)
Full duty ratio
Package
: TSOT-25
■Application
•
•
•
•
•
•
•
Cellular phone
PDA and smart phone
MP3 player
Digital camera
Wireless and DSL card
Microcomputer and DSP power supply
Portable machine
■Maximum absolute ratings
Parameter
VIN power supply voltage
Apply voltage to SW
Apply voltage to EN
Apply voltage to FB
SW peak current
Power dissipation
Operating temperature range
Storage temperature range
Symbol
Vin
Vsw
Ven
Vfb
Isw
Pd
Top
Tstg
Limit
-0.3 to +6.5
GND-0.3 to Vin+0.3
GND-0.3 to Vin+0.3
GND-0.3 to Vin+0.3
1.7
200
-40 to +85
-65 to +150
Unit
V
V
V
V
A
mW
°C
°C
Caution:Permanent damage to the device may occur when ratings above maximum absolute ones are used.
■Selection guide
Symbol
a
b
c, d
e
ELM600LA-S, ELM600LA-xx-S
Package
Product version
Output voltage
Taping direction
L: TSOT-25
A
e.g. :
12: Vout=1.2V, 18: Vout=1.8V
S: Refer to PKG file
• Adj. version
ELM600LA - S
↑↑ ↑
ab e
• Fixed version
* Taping direction is one way.
ELM600 LA - x x - S
↑↑ ↑ ↑ ↑
ab c d e
Rev.1.1
10 - 1