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www.semtech.com
SC5205
150mA Ultra Low Dropout, Low
Noise Micropower Linear Regulator
POWER MANAGEMENT
PRELIMINARY
Revision 1, January 2001
The SC5205 is a 150mA ultra low dropout linear
regulator with a built in CMOS/TTL logic level enable
switch. It is designed specifically for battery powered
applications where low quiescent current and low
dropout are critical for battery longevity.
The SC5205 uses a Semtech proprietary internal PNP
device for the pass element, providing a low dropout
voltage of 165mV at a load of 150mA, while maintaining
a ground pin current of 2750A.
The output noise is reduced by placing a 10nF capacitor
on pin 4 (bypass).
Each device contains a bandgap reference, error
amplifier, PNP pass element, thermal and current
limiting circuitry and resistor divider network for setting
output voltage.
The SC5205 is packaged in a 5 pin SOT-23 surface mount
package for a very small footprint and it requires only a
1F capacitor on the output and a 0.01F on the bypass
pin for a minimum amount of external components.
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Ultra low dropout voltage - 165mV @ 150mA
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Guaranteed 150mA output current
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Low ground pin current at all loads
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<5A quiescent current in shutdown
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Wide input supply voltage range 2.5V to 16V in
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Wide output voltage range
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Excellent line regulation
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Industrial temperature range
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Surface mount packaging (5 pin SOT-23)
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Battery Powered Systems
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Cellular Telephones
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Cordless Telephones
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Pagers
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Personal Digital Assistants
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Portable Instrumentation
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Cameras
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Portable Consumer Equipment
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PCMCIA cards
EN
VIN
VO
+
C1
1uF
U1
SC5205
1
2
3
4
5
VIN
GND
EN
BYP
VO
+
C3
1uF
C2
10nF
Description
Features
Applications
Typical Application Circuit
Notes:
(1) C
IN
(C1) is needed if the device is far from the supplys filter capacitors, or for operation from a battery. A value
of 1.0F or greater should be used. C
IN
may be tantalum or aluminum electrolytic.
(2) C
O
(C3) should be a 1F or greater tantalum or aluminum electrolytic capacitor. Larger value capacitors will
improve the overall transient response.
(3) C
BYP
(C2 - required) should be placed as close as possible to pin 4 and ground. A 10nF ceramic capacitor is
recommended.
(4) EN may be tied to V
IN
if the shutdown feature is not required. Maximum EN voltage = V
IN
.