www.fairchildsemi.com
RC1587
3A Adjustable/Fixed Low Dropout Linear Regulator
Features
• Fast transient response
• Low dropout voltage at up to 3A
• Load regulation: 0.05% typical
• Trimmed current limit
• On-chip thermal limiting
• Standard TO-220, TO-263, TO-263 center cut,
and TO-252 packages
Description
The RC1587, RC1587-1.5, and RC1587-3.3 are low dropout
three-terminal regulators with 3A output current capability.
These devices have been optimized for low voltage applica-
tions including V
TT
bus termination, where transient response
and minimum input voltage are critical. The RC1587 is ideal
for low voltage microprocessor applications requiring a reg-
ulated output from 1.5V to 3.6V with an input supply of 5V
or less. The RC1587-1.5 offers fixed 1.5V with 3A current
capability for GTL+ bus V
TT
termination. The RC1587-3.3
offers fixed 3.3V current capability for logic IC operation.
Current limit is trimmed to ensure specified output current and
controlled short-circuit current. On-chip thermal limiting pro-
vides protection against any combination of overload and
ambient temperature that would create excessive junction
temperatures.
The RC1587, RC1587-1.5, and RC1587-3.3 are available in
the industry-standard TO-220, TO-263, TO-263 center cut,
and TO-252 (DPAK) power packages.
Applications
• Pentium
®
Class GTL+ bus supply
• Low voltage logic supply
• Post regulator for switching supply
Typical Applications
V
IN = 3.3V
10µF
+
RC1587
V
IN
V
OUT
ADJ
R1
124Ω
R2
24.9Ω
V
OUT =
V
REF
(1 + R2/R1) + I
ADJ
*
R2
RC1587-1.5
V
OUT
V
IN
+
10µF
GND
+
+
1.5V at 3A
22µF
V
IN = 3.3V
1.5V at 3A
22µF
V
IN = 5V
+
10µF
RC1587-3.3
V
IN
V
OUT
GND
+
3.3V at 3A
22µF
65-1587-16
Pentium is a registered trademark of Intel Corporation.
REV. 1.5.4 3/25/02
ETC [ ETC ]
