PRELIMINARY
CM3112
PACKAGE / PINOUT DIAGRAM
Top View
IN
1
5
OUT
FA12/FB12
GND
2
EN
3
4
PG
5-pin SOT23
Note: This drawing is not to scale.
PIN DESCRIPTIONS
PIN
1
NAME
IN
DESCRIPTION
Positive input voltage for the regulator. The internal loading on this input is typically 300µA when-
ever the regulator is enabled, and less than 10µA when the regulator is disabled. If the IN pin is
within a few inches of the main input filter, a capacitor may not be necessary. Otherwise an input fil-
ter capacitor (C
IN
) of 0.1uF to 1uF will ensure adequate filtering.
The negative reference for all voltages.
Enable/shutdown input. When EN is asserted high (V
EN
≥
1.6V), the regulator is enabled. When EN
is asserted low (V
EN
≤
0.4V), the regulator’s series pass transistor is forced into a high impedance
mode and an internal discharge resistance (500
Ω
) is applied to the output to quickly reduce the out-
put voltage to 0 volts.
4
PG
Power Good output. This is an open drain output and functions as a supply voltage supervisor for
the output voltage. It is asserted low when the output falls below 84% of its nominal value. This out-
put becomes inactive when (EN > 1.5V), (2.5V < V
IN
< 5.5V) and (V
OUT
> 97% of V
OUTNOM)
, all of
which are valid for more than 1-10ms.
The regulated voltage output. Although an output capacitor is not necessary for stable regulator
operation, a optional 0.1uF capacitor can be used to provide an added measure of output stability.
2
3
GND
EN
5
OUT
Ordering Information
PART NUMBERING INFORMATION
Standard Finish
Ordering Part
Regulator
CM3112-12
Pins
5
Package
SOT23-5
Number
1
CM3112-12ST
Part Marking
FA12
Lead-free Finish
Ordering Part
Number
1
CM3112-12SO
Part Marking
FB12
Note 1: Parts are shipped in Tape & Reel form unless otherwise specified.
© 2004 California Micro Devices Corp. All rights reserved.
2
430 N. McCarthy Blvd., Milpitas, CA 95035-5112
L
Tel: 408.263.3214
L
Fax: 408.263.7846
L
www.calmicro.com
01/20/04