www.fairchildsemi.com
FAN1587A
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 FAN1587A, FAN1587A-1.5, and FAN1587A-3.3 are low
dropout three-terminal regulators with 3A output current capa-
bility. These devices have been optimized for low voltage
applications including V
TT
bus termination, where transient
response and minimum input voltage are critical. The
FAN1587A is ideal for low voltage microprocessor applica-
tions requiring a regulated output from 1.5V to 3.6V with an
input supply of 12V or less. The FAN1587A-1.5 offers fixed
1.5V with 3A current capability for GTL+ bus V
TT
termina-
tion. The FAN1587A-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 FAN1587A, FAN1587A-1.5, and FAN1587A-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
12V to 5V linear regulator
3.3V to 1.5V linear regulator
Typical Applications
V
IN = 12V
22µF
+
FAN1587A
V
IN
V
OUT
ADJ
R1
124Ω
R2
768Ω
+
9V at 3A
22µF
V
OUT =
V
REF
(1+R2/R1)+I
ADJ
*R2
FAN1587A-3.3
V
IN = 9V
+
22µF
V
IN
V
OUT
GND
3.3V at 3A
+
22µF
65-1587-16
Pentium is a registered trademark of Intel Corporation.
REV. 1.0.5 11/10/03
FAN1587A
PRODUCT SPECIFICATION
Pin Assignments
FAN1587AT
FRONT VIEW
FAN1587AT-1.5, -3.3V
FRONT VIEW
FAN1587AM-1.5
FRONT VIEW
FAN1587AM
FRONT VIEW
Tab is Out.
Tab is Out.
1
2
3
1
2
3
1
2
3
1
2
3
GND OUT IN
ADJ OUT IN
ADJ OUT IN
GND OUT IN
3-Lead Plastic TO-263
θ
JC
= 3°C/W*
3-Lead Plastic TO-220
θ
JC
= 3°C/W
FAN1587AMC-1.5, 3.3
FRONT VIEW
FAN1587AMC
FRONT VIEW
FAN1587AD-1.5, 3.3
FRONT VIEW
FAN1587AD
FRONT VIEW
Tab is Out.
Tab is Out.
1
2
3
1
2
3
1
2
3
1
2
3
GND
GND
IN
ADJ
IN
IN
ADJ
IN
3-Lead Plastic TO-252
θ
JC
= 3°C/W*
3-Lead Plastic TO-263 Center Cut
θ
JC
= 3°C/W*
* With package soldered to 0.5 square inch copper area over backside ground plane or internal power plane,
θ
JA
can vary from 30°C/W to more than 40°C/W. Other mounting techniques can provide a thermal resistance
lower than 30°C/W.
2
REV. 1.0.5 11/10/03
PRODUCT SPECIFICATION
FAN1587A
Absolute Maximum Ratings
Parameter
V
IN
(V
IN
– V
OUT
) * I
OUT
Operating Junction Temperature Range
Storage Temperature Range
Lead Temperature (Soldering, 10 sec.)
0
-65
Min.
Max.
18
See Figure 1
125
150
300
°
C
°
C
°
C
Unit
V
4
I
OUT
(Amps)
3
2
1
0
0
2
4
6
8
10
12
14
V
IN
–V
OUT
(V)
Figure 1. Absolute Maximum Safe Operating Area
REV. 1.0.5 11/10/03
3
PRODUCT SPECIFICATION
FAN1587A
Electrical Characteristics
Tj = 25°C unless otherwise specified.
The
•
denotes specifications which apply over the specified operating temperature range.
Parameter
Reference
Voltage
3
Conditions
1.5V
≤
(V
IN
– V
OUT
)
≤
8.25V,
10mA
≤
I
OUT
≤
3A
3.0V
≤
V
IN
≤
8.5V
10mA
≤
I
OUT
≤
3A
4.8V
≤
V
IN
≤
10.3V
10mA
≤
I
OUT
≤
3A
(V
OUT
+ 1.5V)
≤
V
IN
≤
12V,
I
OUT
=
10mA
(V
IN
– V
OUT
) = 3V
10mA
≤
I
OUT
≤
3A
∆
V
REF
= 1%, I
OUT
= 3A
(V
IN
– V
OUT
) = 2V
1.5V
≤
(V
IN
– V
OUT
)
≤
12V,
10mA
≤
I
OUT
≤
3A
1.5V
≤
(V
IN
– V
OUT
)
≤
12V
V
IN
= 5V
f = 120Hz, C
OUT
= 22
µ
F Tantalum,
(V
IN
– V
OUT
) = 3V, I
OUT
= 3A
T
A
= 25
°
C, 30ms pulse
•
T
A
= 125
°
C, 1000 hrs.
T
A
= 25
°
C, 10Hz
≤
f
≤
10kHz
TO-220
TO-263, TO-252
•
•
•
•
•
•
•
•
•
•
•
60
10
4
72
0.004
0.5
0.03
0.003
3
3
150
1.0
0.02
13
3.1
Min.
1.225
(-2%)
1.47
3.234
Typ.
1.250
1.5
3.3
0.005
0.05
1.150
4
35
0.2
120
5
Max
1.275
(+2%)
1.53
3.366
0.2
0.5
1.300
Units
V
V
V
%
%
V
A
µ
A
µ
A
mA
mA
dB
%/W
%
%
%
°
C/W
°
C/W
°C
Output Voltage
4, 6
Output Voltage
5, 6
Line Regulation
1, 2
Load Regulation
1, 2
Dropout Voltage
Current Limit
Adjust Pin Current
3
Adjust Pin Current
Change
3, 6
Minimum Load Current
Quiescent Current
Ripple Rejection
Thermal Regulation
Temperature Stability
Long-Term Stability
RMS Output Noise
(% of V
OUT
)
Thermal Resistance,
Junction to Case
Thermal Shutdown
Notes:
1. See thermal regulation specifications for changes in output voltage due to heating effects. Load and line regulation are
measured at a constant junction temperature by low duty cycle pulse testing.
2. Line and load regulation are guaranteed up to the maximum power dissipation (18W). Power dissipation is determined by
input/output differential and the output currrent. Guaranteed maximum output power will not be available over the full input/
output voltage range.
3. FAN1587A only.
4. FAN1587A-1.5 only.
5. FAN1587A-3.3 only.
6. Output current must be limited to meet the absolute maximum ratings of the part.
REV. 1.0.5 11/10/03
4
FAN1587A
PRODUCT SPECIFICATION
Typical Performance Characteristics
1.5
OUTPUT VOLTAGE DEVIATION (%)
0.10
∆I
= 3A
1.4
DROPOUT VOLTAGE (V)
1.3
1.2
1.1
1.0
0.9
T=25°C
0.8
65-1587-03
0.05
0
T=0°C
T=125°C
-0.05
-0.10
65-1587-04
0.7
0.6
0.5
0
0.5
1
1.5
2
2.5
OUTPUT CURRENT (A)
-0.15
3.0
-0.20
-75 -50 -25
0
25 50 75 100 125 150 175
JUNCTION TEMPERATURE (°C)
Figure 2. Dropout Voltage vs. Output Current
Figure 3. Load Regulation vs. Temperature
1.275
1.270
3.70
3.65
REFERENCE VOLTAGE (V)
3.60
3.55
3.50
3.45
3.40
3.35
3.30
3.25
Note:
1. FAN1587A Only
2. FAN1587A, -3.3
V
OUT
SET WITH 1% RESISTORS
V
OUT
= 3.6V
1
REFERENCE VOLTAGE (V)
1.265
1.260
1.255
1.250
1.245
1.240
1.235
1.230
1.225
-75 -50 -25
0
25 50 75 100 125 150 175
V
OUT
= 3.3V
2
3.20
-75 -50 -25
0
25 50 75 100 125 150 175
JUNCTION TEMPERATURE (°C)
JUNCTION TEMPERATURE (°C)
Figure 4. Reference Voltage vs. Temperature
Figure 5. Output Voltage vs. Temperature
5
MINIMUM LOAD CURRENT (mA)
100
90
ADJUST PIN CURRENT (µA)
Note:
1. FAN1587A Only
4
80
70
60
50
40
30
65-1587-08
3
2
65-1587-07
1
20
10
0
-75 -50 -25
0
0
-75 -50 -25
0
25 50 75 100 125 150 175
25 50 75 100 125 150 175
JUNCTION TEMPERATURE (°C)
JUNCTION TEMPERATURE (°C)
Figure 6. Minimum Load Current vs. Temperature
Figure 7. Adjust Pin Current vs. Temperature
5
REV. 1.0.5 11/10/03
65-1587-06