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FAN1086
1.5A Adjustable/Fixed Low Dropout Linear Regulator
Features
•
•
•
•
•
•
Low dropout voltage
Load regulation: 0.05% typical
Trimmed current limit
On-chip thermal limiting
Standard SOT-223, TO-263, and TO-252 packages
Three-terminal adjustable or fixed 2.5V, 2.85V, 3.3V, 5V
Description
The FAN1086 and FAN1086-2.5, -2.85, -3.3 and -5 are low
dropout three-terminal regulators with 1.5A output current
capability. These devices have been optimized for low voltage
where transient response and minimum input voltage are
critical. The 2.85V version is designed specifically to be
used in Active Terminators for SCSI bus.
Current limit is trimmed to ensure specified output current
and controlled short-circuit current. On-chip thermal limiting
provides protection against any combination of overload and
ambient temperatures that would create excessive junction
temperatures.
Unlike PNP type regulators where up to 10% of the output
current is wasted as quiescent current, the quiescent current
of the FAN1086 flows into the load, increasing efficiency.
The FAN1086 series regulators are available in the industry-
standard SOT-223, TO-263, and TO-252 power packages.
Applications
•
•
•
•
•
•
Active SCSI terminators
High efficiency linear regulators
Post regulators for switching supplies
Battery chargers
5V to 3.3V linear regulators
Motherboard clock supplies
Typical Applications
FAN1086
V
IN
= 3.3V
10µF
ADJ
+
V
IN
V
OUT
R1
124Ω
+
22µF
1.5V at 1.5A
V
OUT
= V
REF
(1 + R2/R1) + I
Adj
• R2
R2
24.9Ω
FAN1086-2.85
V
IN
= 5V
10µF
GND
+
V
IN
V
OUT
+
22µF
2.85V at 1.5A
REV. 1.0.7 11/10/03
PRODUCT SPECIFICATION
FAN1086
Pin Assignments
Front View
3
Tab is
V
OUT
2
1
IN
OUT
ADJ/GND
1
2
3
Tab is
V
OUT
Tab is
V
OUT
4-Lead Plastic SOT-223
Θ
JC
= 15°C/W*
1
2
3
ADJ/
GND
OUT
IN
ADJ/
GND
IN
3-Lead Plastic TO-263
Θ
JC
= 3°C/W*
3-Lead Plastic TO-252
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 50°C/W. Other mounting techniques may provide better thermal resistance 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.
7.5
125
150
300
Unit
V
°
C
°
C
°
C
2
REV. 1.0.7 11/10/03
FAN1086
PRODUCT SPECIFICATION
Electrical Characteristics
Operating Conditions: V
IN
≤
7V, T
J
= 25°C unless otherwise specified.
The
•
denotes specifications which apply over the specified operating temperature range.
Parameter
Reference Voltage
3
, V
REF
Output Voltage
Conditions
1.5V
≤
(V
IN
- V
OUT
)
≤
5.75V,
10mA
≤
I
OUT
≤
1A
10mA
≤
I
OUT
≤
1A
FAN1086-2.5, 4V
≤
V
IN
≤
7V
FAN1086-2.85, 4.35V
≤
V
IN
≤
7V
FAN1086-3.3, 4.8V
≤
V
IN
≤
7V
FAN1086-5, 6.5V
≤
V
IN
≤
7V
(V
OUT
+ 1.5V)
≤
V
IN
≤
7V, I
OUT
= 10mA
(V
IN
– V
OUT
) = 2V, 10mA
≤
I
OUT
≤
1A
∆
V
REF
= 1%, I
OUT
= 1.5A
(V
IN
– V
OUT
) = 2V
1.5V
≤
(V
IN
– V
OUT
)
≤
5.75,
10mA
≤
I
OUT
≤
1A
1.5V
≤
(V
IN
– V
OUT
)
≤
5.75
V
IN
= V
OUT
+ 1.25V
f = 120Hz, C
OUT
= 22
µ
F Tantalum,
(V
IN
– V
OUT
) = 3V, I
OUT
= 1.5A
T
A
= 25
°
C, 30ms pulse
•
T
A
= 125
°
C, 1000hrs.
T
A
= 25
°
C, 10Hz
≤
f
≤
10kHz
SOT-223
TO-263, TO-252
Junction Temperature
1,2
Min.
•
1.225
(-2%)
2.450
2.793
3.234
4.900
Typ.
1.250
Max.
1.275
(+2%)
2.550
2.907
3.366
5.100
0.2
0.5
1.500
120
5
Units
V
•
•
•
•
•
•
•
•
•
•
•
•
2.5
2.85
3.3
5.0
0.005
0.05
1.300
V
V
V
V
%
%
V
A
µ
A
µ
A
mA
Line Regulation
1,2
Load Regulation
Dropout Voltage
Current Limit
Adjust Pin Current
3
, I
Adj
Adjust Pin Current Change
3
Minimum Load Current
Quiescent Current
Ripple Rejection
Thermal Regulation
Temperature Stability
Long-Term Stability
RMS Output Noise
(% of V
OUT
)
Thermal Resistance,
Juncation to Case
Thermal Shutdown
Thermal Shutdown
Hysteresis
1.6
2.0
35
0.2
10
4
60
72
0.004
0.5
0.03
0.003
15
3
155
10
1.0
0.02
13
mA
dB
%/W
%
%
%
°
C/W
°
C/W
°
C
°
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 current. Guaranteed maximum output power will not be available over the full input/output
voltage range.
3. FAN1086 only.
REV. 1.0.7 11/10/03
3
PRODUCT SPECIFICATION
FAN1086
Typical Performance Characteristics
DROPOUT VOLTAGE DEVIATION (%)
1.5
1.4
DROPOUT VOLTAGE (V)
1.3
1.2
1.1
1.0
0.9
0.8
0.7
0.6
0.5
0
0
0.3
0.6
0.9
1.2
1.5
0.10
0.05
0
-0.05
-0.10
-0.15
-0.20
-75 -50 -25 0
∆I
= 1A
25 50 75 100 125 150 175
OUTPUT CURRENT (A)
JUNCTION TEMPERATURE (°C)
Figure 1. Dropout Voltage vs. Output Current
1.250
1.245
REFERENCE VOLTAGE (V)
Figure 2. Load Regulation vs. Temperature
3.70
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
V
OUT
SET WITH 1% RESISTORS
V
OUT
= 3.6V
1
1.240
1.235
1.230
1.225
1.220
1.215
1.210
1.205
1.200
-75 -50 -25 0
25 50 75 100 125 150 175
Note:
1. FAN1086 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
5
MINIMUM LOAD CURRENT (mA)
Figure 4. Output Voltage vs. Temperature
100
90
ADJUST PIN CURRENT (µA)
Note:
1. FAN1086 Only
4
80
70
60
50
40
30
20
10
3
2
1
0
-75 -50 -25 0
25 50 75 100 125 150 175
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. 1.0.7 11/10/03
FAN1086
PRODUCT SPECIFICATION
Typical Performance Characteristics
(continued)
2.0
SHORT-CIRCUIT CURRENT (A)
90
80
RIPPLE REJECTION (dB)
1.75
70
60
50
40
30
20
10
1.0
-75 -50 -25 0
25 50 75 100 125 150 175
0
10
(V
IN
- V
OUT
) = 3V
0.5 < V
RIPPLE
< 2V
I
OUT
= 1A
100
1K
10K
100K
1.5
1.25
JUNCTION TEMPERATURE (°C)
FREQUENCY (Hz)
Figure 7. Short-Circuit Current vs. Temperature
Figure 8. Ripple Rejection vs. Frequency
10
OUTPUT CAP'S ESR (mΩ)
5000
10ma < I
OUT
< I
MAX
7.5
POWER (W)
TO-263
5
4000
3000
V
IN
= 5V
2000
Instability
Region
Region of Stability
(SOA)
2.5
SOT-223
1000
0
25
0
45
65
85
105
125
0
1
2
3
4
5
6
7
8
9
10
CASE TEMPERATURE (°C)
V
OUT
(V)
Figure 9. Maximum Power Dissipation
Figure 11. Stability Region (SOA) vs. ESR of the C
OUT
REV. 1.0.7 11/10/03
5
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