ELM92 Datasheet, PDF (1/14 Pages) ELM Electronics – CMOS 600kHz High output current PWM step-up DC/DC converter

ELM92xxxx CMOS 600kHz High output current PWM step-up DC/DC converter
■General description
ELM92xxxx is CMOS PWM step-up DC/DC converter which consists of reference voltage source, error
amplifier, oscillation circuit, start-up circuit, output voltage setting resistor, LX transistor and switching current
limiter. For external parts, coil, diode and capacitor are possible choices; with external parts, ELM92 series is
able to acquire constant output voltage higher than input voltage. The standard output voltages are 2.7V, 3.0V,
3.3V, and 5.0V; ELM92 series can also be designed as semi-custom IC within the range of 2.5V to 5.5V by 0.1V
step. Meanwhile, 600kHz high frequency PWM control scheme makes it easy to design DC/DC converter which
can generate large output current with high stability and small ripples by only using small external inductor.
With newly developed intermittent operation control scheme, ELM92 series is able to work with high efficiency
under wide range of load conditions.
■Features
• Output voltage range : 2.5V to 5.5V (by 0.1V)
• Low voltage operation : Vin≥0.9V
• Oscillating frequency : Typ.600kHz
• Output current(e.g.) : 250mA(Vin=1.5V, Vout=3.0V)
• CE(Chip-enable pin) available
: Max.0.5μA(ELM92xx2x Iss at shutdown)
• High efficiency
: Typ.85%
• Switching current limiter
• Package
: SOT-89, SOT-89-5
■Application
• Constant voltage source for
battery-operated devices
• Constant voltage source for PDAs,
cameras, portable communications
equipments and videos
• Local regulator
■Maximum absolute ratings
Parameter
Symbol
Limit
Unit
Apply voltage to LX pin
Vlx
Vss-0.3 to 8.0
V
Apply voltage to VOUT pin
Vout
Vss-0.3 to 8.0
V
Apply voltage to CE pin
Vce
Vss-0.3 to 8.0
V
Power dissipation
Pd
500 (SOT-89)
500 (SOT-89-5)
mW
Operating temperature
Top
-40 to +85
°C
Storage temperature
Tstg
-55 to +125
°C
■Selection guide
ELM92xxxx-x
Symbol
a, b
Output voltage
c
CE selection
d
Package
e
Taping direction
e.g. :
27: Vout=2.7V 30: Vout=3.0V
33: Vout=3.3V 50: Vout=5.0V
1: No CE type (SOT-89)
2: CE type (SOT-89-5)
B: SOT-89, SOT-89-5
S: Refer to PKG file
N: Refer to PKG file
ELM92 x x x x - x
↑↑↑↑ ↑
abcd e
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