DUAL INPUT
LOW DROPOUT REGULATOR
February 26, 1999
EZ1580/EZ1581
EZ1582/EZ1583
TYPICAL APPLICATIONS
Adjustable Output Parts
(3)
(1)(2)
U1
1
SENSE
EZ158XCX
VREF
3
3.3V POWER IN
5V CONTROL IN
5
4
POWER
OUTPUT
CONTROL
ADJ
2.5V OUT
R1
124
C3
68uF
C1
33uF
C2
10uF
2
R2
124
GROUND
GROUND
R2
ö
æ
V
OUT
=
V
REF
ç
1
+
+
I
ADJ
•
R 2
R1
è
Fixed Output Parts
U1
1
SENSE
3.3V POWER IN
5V CONTROL IN
5
4
POWER
OUTPUT
CONTROL
GND
C1
33uF
GROUND
C2
10uF
2
C3
68uF
GROUND
3
EZ158XCX-2.5
2.5V OUT
U1
1
SENSE
2.5V POWER IN
3.3V CONTROL IN
5
4
POWER
EZ158XCX-1.5
OUTPUT
CONTROL
GND
C1
47uF
GROUND
C2
10uF
2
3
1.5V OUT
C3
100uF
GROUND
NOTES:
(1) Capacitor values are for reference only. Good quality, low ESR tantalum or aluminum electrolytic capacitors
should be used. Increasing the value of the output capacitor will improve the overall transient response.
(2) If the same voltage is input to both POWER and CONTROL, then the dropout voltage will become 1.3V maxi-
mum.
(3) A small (~0.033µF) capacitor can be used to bypass the ADJUST pin to improve transient response, if needed.
4
© 1999 SEMTECH CORP.
652 MITCHELL ROAD NEWBURY PARK CA 91320
SEMTECH [ SEMTECH CORPORATION ]
