FAN2500-XX Fairchild Semiconductor, FAN2500-XX Datasheet - Page 2

• Manufacturer Part Number: FAN2500-XX
• Description: Low-dropout Voltage Regulator
• Manufacturer: Fairchild Semiconductor

PRODUCT SPECIFICATION
Pin Assignments
Pin Descriptions
Functional Description
Designed utilizing CMOS process technology, the
FAN2500/01 family of products are carefully optimized for
use in compact battery-powered devices, offering a unique
combination of low power consumption, extremely low
dropout voltages, high tolerance for a variety of output
capacitors, and the ability to disable the output to less than
1µA under user control. In the circuit, a difference amplifier
controls the current through a series-pass P-Channel
MOSFET, comparing the load voltage at the output with an
onboard low-drift bandgap reference. The series resistance
of the pass P-Channel MOSFET is approximately 1 ,
resulting in an unusually low dropout voltage under load
when compared to older bipolar pass-transistor designs.
2
Pin Name
V
GND
ERR
BYP
ADJ
V
EN
OUT
IN
Pin No.
1.
2.
3.
4.
5.
Pin No.
4
4
4
3
1
5
2
Type
Input
Passive
Open drain
Digital Input
Power in
Power out
Power
FAN2500
GND
V
GND
ADJ
V
EN
V
EN
OUT
IN
IN
Pin Function Description
FAN2500 Adjust. Ratio of potential divider from VOUT to ADJ
determines output voltage.
FAN2500-XX Bypass. Connect 470 pF capacitor for noise reduction.
FAN2501-XX Error. Error flag output.
0: Output voltage < 95% of nominal.
1: Output voltage > 95% of nominal.
Enable.
0: Shutdown V
1: Enable V
Voltage Input. Supply voltage input.
Voltage Output. Regulated output voltage.
Ground.
1
2
3
OUT
OUT
.
Protection circuitry is provided onboard for overload condi-
tions. In conditions where the device reaches temperatures
exceeding the specified maximums, an onboard circuit shuts
down the output, where it remains suspended until it has
cooled before re-enabling. The user is also free to shut down
the device using the Enable control pin at any time.
Careful design of the output regulator amplifier assures loop
stability over a wide range of ESR values in the external
output capacitor. A wide range of values and types can be
accomodated, allowing the user to select a capacitor meeting
his space, cost, and performance requirements, and enjoy
reliable operation over temperature, load, and tolerance
variations.
5
4
.
FAN2500-XX
V
ADJ/BYP/ERR
OUT
V
GND
BYP
V
EN
OUT
IN
FAN2501-XX
V
GND
ERR
REV. 1.0.6 2/14/03
V
EN
FAN2500/FAN2501
OUT
IN