Diodes AP1184 - Manual (Page 2)

AP1184
4A ULTRA LOW DROPOUT POSITIVE ADJUSTABLE OR
FIXED-MODE REGULATOR
AP1184 Rev. 5 2 of 12 SEPTEMBER 2008
www.diodes.com © Diodes Incorporated
Pin Assignments
TO263-5L
FRONT VIEW
Tab is Vout
3
2
1
Vout
Vsense
Adj(GND)
Vctrl
Vin
4
5
TO220-5L
Tab is Vout
FRONT VIEW
Vout
Vsense
Adj(GND)
Vctrl
Vin 5
2
1
4
3
Pin Numbers with standard type are for TO220-5L, TO263-5L packages.
Name I/O Description
Adj
(GND)
A resistor divider from this pin to the Vout pin and ground sets the output voltage. (GND
only for fixed mode)
Vsense I
This pin is the positive side of the reference that allows remote load sensing to achieve
excellent load regulation. A minimum of 10uF capacitor must be connected from this pin
to ground to insure stability.
Vin I
The input of the regulator. Typically a large storage capacitor is connected from this pin
to ground to insure that the input voltage does not sag below the minimum dropout
voltage during the load transient response. This pin must always be higher than Vout in
order for the device to regulate.
Vctrl I
This pin is the supply pin for the internal control circuit as well as the base drive for the
pass transistor. This pin must always be higher than the Vout pin in order to regulate the
device. A minimum of 100uF capacitor must be connected from this pin to ground to
insure stability.
Vout O
The output of the regulator. A minimum of 100uF capacitor must be connected from this
pin to ground to insure stability.
Block Diagram
THERMAL
SHUTDOWN
Vout
Adj
1.25V
+
CURRENT
LIMIT
Vin
+ -
+
+
-
Vsense
Vctrl
Pin Descriptions