ChipFind - документация

Электронный компонент: FAN1112S

Скачать:  PDF   ZIP
www.fairchildsemi.com
REV. 1.0.1 9/27/01
Features
Low dropout voltage
Load regulation: 0.05% typical
Trimmed current limit
On-chip thermal limiting
Standard SOT-223 and TO-252 packages
Three-terminal fixed 1.2V
Applications
Post regulator for switching supplies
Supply for low-voltage processors
Description
The FAN1112 is a 1.2V low dropout three-terminal
regulator with 1A output current capability. The device has
been optimized for low voltage where transient response and
minimum input voltage are critical.
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 FAN1112 flows into the load, increasing efficiency.
The FAN1112 regulator is available in the industry-standard
SOT-223 and TO-252 (DPAK) power packages.
Typical Application
V
IN
= 3.3V
V
IN
V
OUT
GND
1.2V at 1A
FAN1112
10
F
+
+
22
F
FAN1112
1A 1.2V Low Dropout Linear Regulator
PRODUCT SPECIFICATION
FAN1112
2
REV. 1.0.1 9/27/01
Pin Assignments
*With package soldered to 0.5 square inch copper area over backside ground plane or internal power plane.,
JA
can vary from
30C/W to more than 50C/W. Other mounting techniques may provide better thermal resistance than 30C/W.
Absolute Maximum Ratings
Figure 1. Absolute Maximum Safe Operating Area
Parameter
Min.
Max.
Unit
V
IN
18
V
(V
IN
V
OUT
) * I
OUT
See Figure 1
Operating Junction Temperature Range
0
125
C
Storage Temperature Range
-65
150
C
Lead Temperature (Soldering, 10 sec.)
300
C
Front View
Front View
4-Lead Plastic SOT-223
JC
= 15
C/W*
3-Lead Plastic TO-252
JC
= 3
C/W*
Tab is
V
OUT
Tab is V
OUT
1
GND
OUT
IN
2
3
3
2
1
IN
OUT
GND
1.2
1.0
0.8
0.6
0.4
0.2
0
0
6
8
10
12
14
16
18
20
4
2
V
IN
V
OUT
(V)
I
OUT
(A)
FAN1112
PRODUCT SPECIFICATION
REV. 1.0.1 9/27/01
3
Electrical Characteristics
Operating Conditions: V
IN
7V, T
J
= 25C unless otherwise specified.
The
denotes specifications which apply over the specified operating temperature range.
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. Output current must be limited to meet the absolute maximum ratings of the part.
Parameter
Conditions
Min.
Typ.
Max.
Units
Output Voltage
3
10mA
I
OUT
1A
FAN1112, 3.0V
V
IN
7.2V
1.140
1.200
1.260
V
Line Regulation
1,2
3.0V
V
IN
12V, I
OUT
= 10mA
0.005
0.2
%
Load Regulation
1,2
(V
IN
V
OUT
) = 2V, 10mA
I
OUT
1A
0.05
0.5
%
Dropout Voltage
V
REF
= 1%, I
OUT
= 1A
1.100
1.200
V
Current Limit
(V
IN
V
OUT
) = 2V
1.1
1.5
A
GND Pin Current
35
120
A
GND Pin Current Change
3.0V
V
IN
7V, 10mA
I
OUT
1A
0.2
5
A
Minimum Load Current
3.0V
V
IN
15V
10
mA
Quiescent Current
V
IN
= 7V
4
13
mA
Ripple Rejection
f = 120Hz, C
OUT
= 22
F Tantalum,
(V
IN
V
OUT
) = 3V, I
OUT
= 1A
60
72
dB
Thermal Regulation
T
A
= 25
C, 30ms pulse
0.004
0.02
%/W
Temperature Stability
0.5
%
Long-Term Stability
T
A
= 125
C, 1000hrs.
0.03
1.0
%
RMS Output Noise
(% of V
OUT
)
T
A
= 25
C, 10Hz
f
10kHz
0.003
%
Thermal Resistance, Junction
to Case
SOT-223
15
C/W
TO-252
3
C/W
Thermal Shutdown
Junction Temperature
155
C
Thermal Shutdown
Hysteresis
10
C
PRODUCT SPECIFICATION
FAN1112
4
REV. 1.0.1 9/27/01
Typical Performance Characteristics
1.5
0.10
0.05
0
-0.05
-0.10
-0.15
-0.20
1.4
1.3
1.2
1.1
1.0
0.9
0.8
0.7
0.6
0.5
1.225
1.220
1.215
1.210
1.205
1.200
1.195
1.190
1.185
1.180
1.175
0
0
0.6
0.8
0.4
0.2
OUTPUT CURRENT (A)
JUNCTION TEMPERATURE (
C)
JUNCTION TEMPERATURE (
C)
DR
OPOUT V
O
L
T
A
GE
(V)
OUTPUT V
O
L
T
A
GE
(V)
100
90
80
70
60
50
40
30
20
10
0
ADJUST PIN CURRENT (
A)
5
4
3
2
1
0
MINIMUM LO
AD CURRENT (mA)
DR
OPOUT
V
O
L
T
A
GE DEVIA
T
ION (%)
1.0
-75 -50 -25 0
25 50 75 100 125 150 175
-75 -50 -25 0
25 50 75 100 125 150 175
JUNCTION TEMPERATURE (
C)
-75 -50 -25 0
25 50 75 100 125 150 175
JUNCTION TEMPERATURE (
C)
-75 -50 -25 0
25 50 75 100 125 150 175
T
J
= 125
C
T
J
= 0
C
T
J
= 25
C
I = 1A
2.0
1.75
1.5
1.25
1.0
SHOR
T
-
CIRCUIT CURRENT (A)
JUNCTION TEMPERATURE (
C)
-75 -50 -25 0
25 50 75 100 125 150 175
Figure 2. Dropout Voltage vs. Output Current
Figure 3. Load Regulation vs. Temperature
Figure 4. Reference Voltage vs. Temperature
Figure 5. Minimum Load Current vs. Temperature
Figure 6. GND Pin Current vs. Temperature
Figure 7. Short-Circuit Current vs. Temperature
FAN1112
PRODUCT SPECIFICATION
REV. 1.0.1 9/27/01
5
Typical Performance Characteristics
(continued)
10
7.5
5
2.5
0
PO
WER (W)
CASE TEMPERATURE (
C)
25
45
65
85
105
125
TO-252
SOT-223
90
80
70
60
50
40
30
20
10
0
RIPPLE REJECTION (dB)
FREQUENCY (Hz)
10
100
1K
10K
100K
(V
IN
- V
OUT
) = 3V
0.5 < V
RIPPLE
< 2V
I
OUT
= 1A
Figure 8. Ripple Rejection vs. Frequency
Figure 9. Maximum Power Dissipation