www.fairchildsemi.com
FAN1585A
5A Adjustable/Fixed Low Dropout Linear Regulator
Features
•
•
•
•
•
•
Fast transient response
Low dropout voltage at up to 5A
Load regulation: 0.05% typical
Trimmed current limit
On-chip thermal limiting
Packages: TO-220, TO-252, TO-263 and TO-263 Centercut
Description
The FAN1585A, FAN1585A-1.5, and FAN1585A-1.8 are
low dropout three-terminal regulators with 5A output current
capability. These devices have been optimized for low volt-
age applications including V
TT
bus termination for FC-PGA,
where transient response and minimum input voltage are
critical. The FAN1585A-1.5 offers fixed 1.5V with 5A
current capabilities for AGTL+ bus V
TT
termination for
FC-PGA. The FAN1585A is ideal for low voltage micro-
processor applications requiring a regulated output from
1.5V to 3.6V with an input supply of 5V or less, or for
FC-PGA applications with significant trace resistance.
Current limit is trimmed to ensure specified output current
and controlled short-circuit current. On-chip thermal limit-
ing provides protection against any combination of overload
and ambient temperature that would create excessive junc-
tion temperatures.
The FAN1585A series regulators are available in the industry-
standard TO-220, TO-252, TO-263 and TO-263 Centercut
power packages.
Applications
•
•
•
•
•
AGTL+ bus supply for FC-PGA
Low voltage logic supply
Post regulator for switching supply
3.3V to 1.5V linear regulator
5V to 1.8V linear regulator
Typical Applications
V
IN = 3.3V
22µF
+
FAN1585A
V
OUT
V
IN
ADJ
R1
124Ω
R2
24.9Ω
V
OUT
= V
REF
(1 + R2/R1) + I
Adj
• R2
+
1.5V at 5A
22µF
V
IN = 3.3V
+
22µF
FAN1585A-1.5
V
IN
V
OUT
GND
+
1.5V at 5A
22µF
REV. 1.1.6 7/8/05
FAN1585A
PRODUCT SPECIFICATION
Pin Assignments
FRONT VIEW
Tab is Out.
1
2
3
FRONT VIEW
Tab is V
OUT
FRONT VIEW
FRONT VIEW
Tab is Out.
1
1
2
3
2
3
1
2
3
Tab is Out.
ADJ/ OUT IN
GND
3-Lead Plastic TO-220
θ
JC
= 3°C/W
ADJ/ OUT
GND
IN
ADJ/ OUT IN
GND
3-Lead Plastic TO-263
θ
JC
= 3°C/W*
ADJ/
GND
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.
Absolute Maximum Ratings
Parameter
V
IN
Operating Junction Temperature Range
Storage Temperature Range
Lead Temperature (Soldering, 10 sec.)
0
-65
Min.
Max.
18
125
150
300
Unit
V
°C
°C
°C
7
6
5
I
OUT
(Amps)
4
3
2
1
0
0
2
4
6
8
10
12
14
V
IN
–V
OUT
(V)
Absolute Maximum Safe Operating Area
2
REV. 1.1.6 7/8/05
PRODUCT SPECIFICATION
FAN1585A
Electrical Characteristics
Tj = 25°C unless otherwise specified.
The
•
denotes specifications which apply over the specified operating temperature range.
Parameter
Reference Voltage
3
Output Voltage
4
Output Voltage
5
Line Regulation
1, 2
Load Regulation
1, 2, 3
Dropout Voltage
Current Limit
Adjust Pin Current
3
Adjust Pin Current Change
3
1.5V
≤
(V
IN
– V
OUT
)
≤
5.75V,
10mA
≤
I
OUT
≤
5A
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
T
A
= 125°C, 1000 hrs.
T
A
= 25°C, 10Hz
≤
f
≤
10kHz
TO-220, TO-252, TO-263, and
TO-263 CC
1.5V
≤
(V
IN
– V
OUT
)
≤
12V
V
IN
= 5V
f = 120Hz, C
OUT
= 22µF Tantalum,
(V
IN
– V
OUT
) = 3V, I
OUT
= 5A
T
A
= 25°C, 30ms pulse
•
Conditions
1.5V
≤
(V
IN
– V
OUT
)
≤
5.75V,
10mA
≤
I
OUT
≤
5A
3.0V
≤
V
IN
≤
8V
10mA
≤
I
OUT
≤
5A
3.3V
≤
V
IN
≤
8.3V
10mA
≤
I
OUT
≤
5A
(V
OUT
+ 1.5V)
≤
V
IN
≤
12V,
I
OUT
=
10mA
(V
IN
– V
OUT
) = 3V,
10mA
≤
I
OUT
≤
5A
∆V
REF
= 1%, I
OUT
= 5A
(V
IN
– V
OUT
) = 2V
•
•
•
•
•
•
•
•
•
•
•
60
10
4
72
0.004
0.5
0.03
0.003
3
150
1.0
0.02
13
5.1
Min.
1.225
(-2%)
1.47
1.764
Typ.
1.250
1.5
1.8
0.005
0.05
1.150
5.9
35
0.2
120
5
Max
1.275
(+2%)
1.53
1.836
0.2
0.5
1.300
Units
V
V
V
%
%
V
A
µA
µA
mA
mA
dB
%/W
%
%
%
°C/W
°C
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. 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. FAN1585A only.
4. FAN1585A-1.5 only.
5. FAN1585A-1.8 only.
REV. 1.1.6 7/8/05
3
FAN1585A
PRODUCT SPECIFICATION
Typical Performance Characteristics
1.5
OUTPUT VOLTAGE DEVIATION (%)
0.10
1.4
DROPOUT VOLTAGE (V)
1.3
1.2
1.1
1.0
0.9
T=25°C
0.8
0.7
0.6
0.5
0
1
2
3
4
5
6
OUTPUT CURRENT (A)
T=0°C
T=125°C
∆I
= 5A
0.05
0
-0.05
-0.10
-0.15
-0.20
-75 -50 -25
0
25 50 75 100 125 150 175
JUNCTION TEMPERATURE (°C)
Figure 1. Dropout Voltage vs. Output Current
Figure 2. Load Regulation vs. Temperature
1.275
1.270
3.70
V
OUT
set with 1% Resistors
3.65
REFERENCE VOLTAGE (V)
3.60
3.55
3.50
3.45
3.40
3.35
3.30
3.25
V
OUT
= 3.3V
1
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
Note:
1. FAN1585A Only
3.20
-75 -50 -25
0
25 50 75 100 125 150 175
JUNCTION TEMPERATURE (°C)
JUNCTION TEMPERATURE (°C)
Figure 3. Reference Voltage vs. Temperature
Figure 4. Output Voltage vs. Temperature
5
MINIMUM LOAD CURRENT (mA)
100
90
Note:
1. FAN1585A Only
4
ADJUST PIN CURRENT (µA)
0
25 50 75 100 125 150 175
80
70
60
50
40
30
20
10
3
2
1
0
-75 -50 -25
0
-75 -50 -25
0
25 50 75 100 125 150 175
JUNCTION TEMPERATURE (°C)
JUNCTION TEMPERATURE (°C)
Figure 5. Minimum Load Current vs. Temperature
Figure 6. Adjust Pin Current vs. Temperature
4
REV. 1.1.6 7/8/05
PRODUCT SPECIFICATION
FAN1585A
Typical Performance Characteristics
(continued)
8.0
SHORT-CIRCUIT CURRENT (A)
90
80
RIPPLE REJECTIONS (dB)
7.0
70
60
50
40
30
20
10
(V
IN
– V
OUT
)
≤
3V
0.5V
≤
V
RIPPLE
≤
2V
I
OUT
= 5A
100
1K
FREQUENCY (Hz)
10K
100K
6.0
5.0
4.0
-75 -50 -25
0
25 50 75 100 125 150 175
0
10
JUNCTION TEMPERATURE (°C)
Figure 7. Short-Circuit Current vs. Temperature
Figure 8. Ripple Rejection vs. Frequency
20
OUTPUT CAPACITANCE ESR, (Ω)
2.5
2
POWER (W)
15
1.5
Area of Instability
1
10
5
0.5
Stable Area
0
0
1000
2000
3000
4000
5000
LOAD CURRENT (mA)
0
50 60 70 80 90 100 110 120 130 140 150
CASE TEMPERATURE (°C)
Figure 9. Maximum Power Dissipation
Figure 10. Stability Region V
IN
/V
OUT
= 5V/1.5V
REV. 1.1.6 7/8/05
5