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FAN1117A
1A 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-220, and TO-252 packages
Three-terminal adjustable or fixed 1.8V, 2.5V, 2.85V,
3.3V, 5V
Description
The FAN1117A and FAN1117A-1.8, -2.5, -2.85, -3.3 and -5
are low dropout three-terminal regulators with 1A 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 FAN1117A flows into the load, increasing efficiency.
The FAN1117A series regulators are available in the
industry-standard SOT-223, TO-220, and TO-252 (DPAK)
power packages.
Applications
•
•
•
•
•
•
Active SCSI terminators
High efficiency linear regulators
Post regulators for switching supplies
Battery chargers
12V to 5V linear regulators
Motherboard clock supplies
Typical Applications
FAN1117A
V
IN
= 12V
10µF
ADJ
R1
124Ω
+
V
IN
V
OUT
+
22µF
9V at 1A
V
OUT
= V
REF
(1 + R2/R1) + I
ADJ
• R2
R2
768Ω
FAN1117A-5
V
IN
= 12V
10µF
GND
+
V
IN
V
OUT
+
22µF
5V at 1A
REV. 1.1.0 11/7/03
PRODUCT SPECIFICATION
FAN1117A
Pin Assignments
Front View
Tab is V
OUT
Front View
Tab is V
OUT
Front View
3
Tab is
V
OUT
2
1
IN
OUT
ADJ/GND
ADJ/ OUT
GND
4-Lead Plastic SOT-223
Θ
JC
= 15°C/W*
IN
ADJ/ OUT IN
GND
3-Lead Plastic TO-220
Θ
JC
= 3°C/W*
1
2
3
1
2
3
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
(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
1.2
1.0
I
OUT
(A)
0.8
0.6
0.4
0.2
0
0
2
4
6
8
10
V
IN
– V
OUT
(V)
12
14
16
18
20
Figure 1. Absolute Maximum Safe Operating Area
2
REV. 1.1.0 11/7/03
FAN1117A
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
Conditions
1.5V
≤
(V
IN
– V
OUT
)
≤
7V,
10mA
≤
I
OUT
≤
1A
10mA
≤
I
OUT
≤
1A
FAN1117A-1.8, 3.3V
≤
V
IN
≤
8.8V
FAN1117A-2.5, 4V
≤
V
IN
≤
9.5V
FAN1117A-2.85, 4.35V
≤
V
IN
≤
9.85V
FAN1117A-3.3, 4.8V
≤
V
IN
≤
10.3V
FAN1117A-5, 6.5V
≤
V
IN
≤
12V
(V
OUT
+ 1.5V)
≤
V
IN
≤
12V, I
OUT
= 10mA
(V
IN
– V
OUT
) = 2V, 10mA
≤
I
OUT
≤
1A
∆
V
REF
= 1%, I
OUT
= 1A
(V
IN
– V
OUT
) = 2V
•
Min.
1.225
(-2%)
1.764
2.450
2.793
3.234
4.900
Typ.
1.250
Max.
1.275
(+2%)
1.836
2.550
2.907
3.366
5.100
0.2
0.5
1.200
120
5
Units
V
Output Voltage
4
•
•
•
•
•
•
•
•
•
•
•
•
•
1.8
2.5
2.85
3.3
5.0
0.005
0.05
1.100
V
V
V
V
V
%
%
V
A
µ
A
µ
A
mA
Line Regulation
1,2
Load Regulation
1,2
Dropout Voltage
Current Limit
Adjust Pin Current
3
1.1
1.5
35
0.2
Adjust Pin Current Change
3,4
1.5V
≤
(V
IN
– V
OUT
)
≤
7V,
10mA
≤
I
OUT
≤
1A
Minimum Load Current
Quiescent Current
Ripple Rejection
Thermal Regulation
Temperature Stability
Long-Term Stability
RMS Output Noise
(% of V
OUT
)
T
A
= 125
°
C, 1000hrs.
T
A
= 25
°
C, 10Hz
≤
f
≤
10kHz
1.5V
≤
(V
IN
– V
OUT
)
≤
15V
V
IN
= V
OUT
+ 1.25V
f = 120Hz, C
OUT
= 22
µ
F Tantalum,
(V
IN
– V
OUT
) = 3V, I
OUT
= 1A
T
A
= 25
°
C, 30ms pulse
10
4
60
72
0.004
0.02
1.0
13
mA
dB
%/W
%
%
%
°
C/W
°C/W
°C
°C
•
0.5
0.03
0.003
15
3
155
10
Thermal Resistance, Junction SOT-223
to Case
TO-252, TO-220
Thermal Shutdown
Thermal Shutdown
Hysteresis
Junction Temperature
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 current. Guaranteed maximum output power will not be available over the full input/
output voltage range.
3. FAN1117A only.
4. Output current must be limited to meet the absolute maximum ratings of the part.
REV. 1.1.0 11/7/03
3
PRODUCT SPECIFICATION
FAN1117A
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
0.2
0.4
0.6
0.8
1.0
T
J
= 25°C
T
J
= 125°C
T
J
= 0°C
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 2. Dropout Voltage vs. Output Current
1.260
1.255
REFERENCE VOLTAGE (V)
1.250
1.245
1.240
1.235
1.230
1.225
1.220
1.215
1.210
-75 -50 -25 0
25 50 75 100 125 150 175
REFERENCE VOLTAGE (V)
Figure 3. Load Regulation vs. Temperature
3.70
3.65
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
Note:
1. FAN1117A Only
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
5
MINIMUM LOAD CURRENT (mA)
ADJUST PIN CURRENT (µA)
Figure 5. Output Voltage vs. Temperature
100
90
Note:
1. FAN1117A 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 6. Minimum Load Current vs. Temperature
Figure 7. Adjust Pin Current vs. Temperature
4
REV. 1.1.0 11/7/03
FAN1117A
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 8. Short-Circuit Current vs. Temperature
Figure 9. Ripple Rejection vs. Frequency
10
OUTPUT CAP'S ESR (mΩ)
5000
V
IN
= 12V
4000
10ma < I
OUT
< I
MAX
7.5
POWER (W)
TO-252, TO-220
5
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 10. Maximum Power Dissipation
Figure 11. Stability Region (SOA) vs. ESR of the C
OUT
REV. 1.1.0 11/7/03
5