UTC LD1117AL-12-TN3-B-R Low drop fixed and adjustable positive voltage regulator Datasheet

UNISONIC TECHNOLOGIES CO., LTD
LD1117/A
LINEAR INTEGRATED CIRCUIT
LOW DROP FIXED AND
ADJUSTABLE POSITIVE
VOLTAGE REGULATORS
„
DESCRIPTION
The UTC LD1117/A is a low dropout, 3-terminal positive
voltage regulator designed to provide output current up to
800mA/1A, There are adjustable version (VREF=1.25V) and various
fixed versions.
„
FEATURES
* Low dropout voltage
* Suitable for SCSI-2 active termination if VOUT set to 2.85V
* Output current up to 0.8A for 1117 and 1.0A for 1117A
* Built-in current limit and over temperature protection
* Available in ±1%(at 25°C) and 2% in all temperature range
* Low current consumption
„
*Pb-free plating product number:
LD1117L-xx / LD1117AL-xx
ORDERING INFORMATION
Order Number
Normal
Lead Free Plating
LD1117①-xx-AA3-②-③
LD1117①L-xx-AA3-②-③
LD1117①-xx-AB3-②-③
LD1117①L-xx-AB3-②-③
LD1117①-xx-TA3-②-③
LD1117①L-xx-TA3-②-③
LD1117①-xx-TN3-②-③
LD1117①L-xx-TN3-②-③
LD1117①-xx-TQ2-②-③
LD1117①L-xx-TQ2-②-③
LD1117①-xx-TQ3-②-③
LD1117①L-xx-TQ3-②-③
LD1117①-xx-S08-②-③
LD1117①L-xx-S08-②-③
Note: Pin Assignment: I:VIN O:VOUT G:GND
www.unisonic.com.tw
Copyright © 2005 Unisonic Technologies Co., Ltd
Package
SOT-223
SOT-89
TO-220
TO-252
TO-263
TO-263-3
SOP-8
②
Pin Assignment
A: GOI
B: OGI
C: GIO
D: IGO
③
Packing
R: Tape Reel
T: Tube
GOOIxOOx
1 of 12
QW-R102-006,Q
LD1117/A
„
LINEAR INTEGRATED CIRCUIT
MARKING INFORMATION
PACKAGE
VOLTAGE CODE
MARKING
SOT-89
SOT-223
12
15
18
25
2J
30
33
36
50
AD
:1.2V
:1.5V
:1.8V
:2.5V
:2.85V
:3.0V
:3.3V
:3.6V
:5.0V
:ADJ
TO-220
TO-252
TO-263
TO-263-3
Note: Current code:
„
Blank: 0.8A
A: 1A
PIN CONFIGURATION
GND
1
8
NC
VOUT
2
7
VOUT
VOUT
3
6
VOUT
VIN
4
5
NC
UNISONIC TECHNOLOGIES CO., LTD
www.unisonic.com.tw
2 of 12
QW-R102-006,Q
LD1117/A
„
LINEAR INTEGRATED CIRCUIT
BLOCK DIAGRAM
UNISONIC TECHNOLOGIES CO., LTD
www.unisonic.com.tw
3 of 12
QW-R102-006,Q
LD1117/A
„
LINEAR INTEGRATED CIRCUIT
ABSOLUTE MAXIMUM RATINGS (Ta=25℃)
PARAMETER
SYMBOL
RATINGS
DC Input Voltage
VIN
18
Power Dissipation
PD
Internally limited
Junction Temperature
TJ
+150
Storage temperature
TSTG
-65 ~ +150
Note Absolute maximum ratings are those values beyond which the device could be permanently damaged.
Absolute maximum ratings are stress ratings only and functional device operation is not implied.
„
°C
°C
RECOMMENDED OPERATING RATINGS
PARAMETER
Input Voltage
Operating Junction Temperature Range
„
UNIT
V
SYMBOL
VIN
TJ
RATINGS
15
0 ~ +125
UNIT
V
°C
ELECTRICAL CHARACTERISTICS
(Ta=25℃, refer to the test circuits, TJ=0 to 125°C, Co=10μF unless otherwise specified)
For LD1117/A-1.2
PARAMETER
Output Voltage
Output Voltage
Line Regulation
Load Regulation
Temperature stability
Long Term Stability
Operating Input Voltage
Quiescent Current
Current Limit
Minimum Load Current
Output Noise Voltage
Supply Voltage Rejection
Dropout Voltage
Thermal Regulation
SYMBOL
TEST CONDITIONS
VOUT VIN=3.2V, IOUT=10mA, TJ=25°C
VIN=2.7 to 8V
VOUT LD1117 : IOUT=0 ~ 800mA
LD1117A : IOUT=0 ~ 1.0A
ΔVOUT VIN=2.7 to 8V, IOUT=0mA
VIN=2.7V
ΔVOUT LD1117 : IOUT=0 ~ 800mA
LD1117A : IOUT=0 ~ 1000mA
ΔVOUT
ΔVOUT 1000 hrs, TJ =125°C
VIN
IOUT=100mA
IQ
VIN≤10V
LD1117
ILIMIT VIN=6.2V, TJ =25°C
LD1117A
IO(MIN) VIN=15V
eN
B=10Hz to 10KHz, TJ =25°C
IOUT=40mA, f=120Hz, TJ =25°C,
SVR
VIN=4.2V, VRIPPLE=1Vpp
IOUT=100mA
IOUT=500mA
VD
IOUT=800mA
IOUT=1000 mA
Ta=25°C, 30ms Pulse
UNISONIC TECHNOLOGIES CO., LTD
www.unisonic.com.tw
MIN.
1.188
TYP.
1.200
MAX.
1.212
UNIT
V
1.176
1.200
1.224
V
1
6
mV
1
10
mV
15
10
%
%
V
mA
0.5
0.3
5
800
1000
mA
2
100
60
5
75
1.00
1.15
1.20
1.20
0.01
mA
μV
dB
1.10
1.25
1.30
1.30
0.10
V
V
V
V
%/W
4 of 12
QW-R102-006,Q
LD1117/A
„
LINEAR INTEGRATED CIRCUIT
ELECTRICAL CHARACTERISTICS(Cont.)
For LD1117/A-1.5
PARAMETER
Output Voltage
Output Voltage
Line Regulation
Load Regulation
Temperature stability
Long Term Stability
Operating Input Voltage
Quiescent Current
Current Limit
Output Noise Voltage
Supply Voltage Rejection
Dropout Voltage
Thermal Regulation
For LD1117/A-1.8
PARAMETER
Output Voltage
Output Voltage
Line Regulation
Load Regulation
Temperature stability
Long Term Stability
Operating Input Voltage
Quiescent Current
Current Limit
Output Noise Voltage
Supply Voltage Rejection
Dropout Voltage
Thermal Regulation
SYMBOL
TEST CONDITIONS
VOUT VIN=3.5V, IOUT=10mA, TJ=25°C
VIN=3 to 8V
VOUT LD1117 : IOUT=0 ~ 800mA
LD1117A : IOUT=0 ~ 1.0A
ΔVOUT VIN=3 to 8V, IOUT=0mA
VIN=3V
ΔVOUT LD1117 : IOUT=0 ~ 800mA
LD1117A : IOUT=0 ~ 1000mA
ΔVOUT
ΔVOUT 1000 hrs, TJ =125°C
VIN
IOUT=100mA
IQ
VIN≤10V
LD1117
ILIMIT VIN=6.5V, TJ =25°C
LD1117A
eN
B=10Hz to 10KHz, TJ =25°C
IOUT=40mA, f=120Hz, TJ =25°C,
SVR
VIN=4.5V, VRIPPLE=1Vpp
IOUT=100mA
IOUT=500mA
VD
IOUT=800mA
IOUT=1000 mA
Ta=25°C, 30ms Pulse
SYMBOL
TEST CONDITIONS
VOUT VIN=3.8V, IOUT=10mA, TJ =25°C
VIN=3.3 to 8V
VOUT LD1117 : IOUT=0 ~ 800mA
LD1117A : IOUT=0 ~ 1000mA
ΔVOUT VIN=3.3 to 8V, IOUT=0mA
VIN=3.3V
ΔVOUT LD1117 : IOUT=0 ~ 800mA
LD1117A : IOUT=0 ~ 1000mA
ΔVOUT
ΔVOUT 1000 hrs, TJ =125°C
VIN
IOUT=100mA
IQ
VIN≤8V
LD1117
ILIMIT VIN=6.8V, TJ =25°C
LD1117A
eN
B=10Hz to 10KHz, TJ =25°C
IOUT=40mA, f=120Hz, TJ =25°C,
SVR
VIN=5.5V, Vripple=1Vpp
IOUT=100mA
IOUT=500mA
VD
IOUT=800mA
IOUT=1000 mA
Ta=25°C, 30ms Pulse
UNISONIC TECHNOLOGIES CO., LTD
www.unisonic.com.tw
MIN.
1.485
TYP.
1.500
MAX.
1.515
UNIT
V
1.470
1.500
1.530
V
1
6
mV
1
10
mV
15
10
%
%
V
mA
0.5
0.3
5
800
1000
60
mA
100
μV
75
dB
1.00
1.15
1.20
1.20
0.01
1.10
1.25
1.30
1.30
0.10
V
V
V
V
%/W
MIN.
1.780
TYP.
1.800
MAX.
1.820
UNIT
V
1.760
1.800
1.840
V
1
6
mV
1
10
mV
10
10
%
%
V
mA
0.5
0.3
5
800
1000
60
mA
100
μV
75
dB
1.00
1.15
1.20
1.20
0.01
1.10
1.25
1.30
1.30
0.10
V
V
V
V
%/W
5 of 12
QW-R102-006,Q
LD1117/A
„
LINEAR INTEGRATED CIRCUIT
ELECTRICAL CHARACTERISTICS(Cont.)
For LD1117/A-2.5
PARAMETER
SYMBOL
Output Voltage
VOUT
Output Voltage
VOUT
Line Regulation
ΔVOUT
Load Regulation
ΔVOUT
Temperature stability
Long Term Stability
Operating Input Voltage
Quiescent Current
ΔVOUT
ΔVOUT
VIN
IQ
Current Limit
ILIMIT
Output Noise Voltage
Supply Voltage Rejection
eN
SVR
Dropout Voltage
VD
Thermal Regulation
For LD1117/A-2.85
PARAMETER
Output Voltage
SYMBOL
VOUT
Output Voltage
VOUT
Line Regulation
ΔVOUT
Load Regulation
ΔVOUT
Temperature stability
Long Term Stability
Operating Input Voltage
Quiescent Current
ΔVOUT
ΔVOUT
VIN
IQ
Current Limit
ILIMIT
Output Noise Voltage
Supply Voltage Rejection
eN
SVR
Dropout Voltage
Thermal Regulation
VD
TEST CONDITIONS
VIN=4.5V,IOUT=10mA,
TJ=25°C
VIN=3.9 to 10V
LD1117 : IOUT=0 ~ 800mA
LD1117A : IOUT=0 ~ 1.0A
VIN=3.9 to 10V, IOUT=0mA
VIN=3.9V
LD1117 : IOUT=0 ~ 800mA
LD1117A : IOUT=0 ~ 1000mA
MIN.
2.475
2.450
TYP.
2.500
2.500
MAX.
2.525
2.550
2%
2.450
2.500
2.550
4%
2.400
2.500
2.600
1
6
mV
1
10
mV
15
10
%
%
V
mA
0.5
0.3
1000 hrs, TJ =125°C
IOUT=100mA
VIN≤10V
LD1117
LD1117A
B=10Hz to 10KHz, TJ =25°C
IOUT=40mA, f=120Hz, TJ =25°C,
VIN=5.5V, Vripple=1Vpp
IOUT=100mA
IOUT=500mA
IOUT=800mA
IOUT=1000 mA
Ta=25°C, 30ms Pulse
VIN=7.5V, TJ =25°C
TEST CONDITIONS
VIN=4.85V, IOUT=10mA, TJ =25°C
VIN=4.25 to 10V
LD1117 : IOUT=0 ~ 800mA
LD1117A : IOUT=0 ~ 1.0A
VIN=4.25 to 10V, Io=0mA
VIN=4.25V
LD1117 : IOUT=0 ~ 800mA
LD1117A : IOUT=0 ~ 1000mA
5
800
1000
60
LD1117
LD1117A
B=10Hz to 10KHz, TJ =25°C
IOUT=40mA, f=120Hz, TJ =25°C,
VIN=5.85V, Vripple=1Vpp
IOUT=100mA
IOUT=500mA
IOUT=800mA
IOUT=1000 mA
Ta=25°C, 30ms Pulse
VIN=7.85V, TJ =25°C
UNIT
V
V
mA
100
μV
75
dB
1.00
1.15
1.20
1.20
0.01
1.10
1.25
1.30
1.30
0.10
V
V
V
V
%/W
MIN.
TYP.
MAX.
UNIT
2.828
2.850
2.880
V
2.790
2.850
2.910
V
1
6
mV
1
10
mV
15
10
%
%
V
mA
0.5
0.3
1000 hrs, TJ =125°C
IOUT=100mA
VIN≤10V
UNISONIC TECHNOLOGIES CO., LTD
www.unisonic.com.tw
1%
2%
5
800
1000
60
mA
100
μV
75
dB
1.00
1.15
1.20
1.20
0.01
1.10
1.25
1.30
1.30
0.10
V
V
V
V
%/W
6 of 12
QW-R102-006,Q
LD1117/A
„
LINEAR INTEGRATED CIRCUIT
ELECTRICAL CHARACTERISTICS(Cont.)
For LD1117/A-3.0
PARAMETER
SYMBOL
Output Voltage
VOUT
Output Voltage
VOUT
Line Regulation
ΔVOUT
Load Regulation
ΔVOUT
Temperature stability
Long Term Stability
Operating Input Voltage
Quiescent Current
ΔVOUT
ΔVOUT
VIN
IQ
Current Limit
ILIMIT
Output Noise Voltage
Supply Voltage Rejection
eN
SVR
Dropout Voltage
VD
Thermal Regulation
For LD1117/A-3.3
PARAMETER
SYMBOL
Output Voltage
VOUT
Output Voltage
VOUT
Line Regulation
ΔVOUT
Load Regulation
ΔVOUT
Temperature stability
Long Term Stability
Operating Input Voltage
Quiescent Current
ΔVOUT
ΔVOUT
VIN
IQ
Current Limit
ILIMIT
Output Noise Voltage
Supply Voltage Rejection
eN
SVR
Dropout Voltage
Thermal Regulation
VD
TEST CONDITIONS
VIN=5V,IOUT=10mA,TJ =25°C
VIN=4.5 to 10V
LD1117 : IOUT=0 ~ 800mA
LD1117A : IOUT=0 ~ 1.0A
VIN=4.5 to 12V, IOUT=0mA
VIN=4.5V
LD1117 : IOUT=0 ~ 800mA
LD1117A : IOUT=0 ~ 1000mA
MIN.
2.970
2.940
TYP.
3.000
3.000
MAX.
3.030
3.060
2%
2.940
3.000
3.060
4%
2.880
3.000
3.120
1
6
mV
1
10
mV
15
10
%
%
V
mA
0.5
0.3
1000 hrs, TJ =125°C
IOUT=100mA
VIN≤10V
5
LD1117
LD1117A
B=10Hz to 10KHz, TJ =25°C
IOUT=40mA, f=120Hz, TJ =25°C,
VIN=6V, VRIPPLE=1Vpp
IOUT=100mA
IOUT=500mA
IOUT=800mA
IOUT=1000 mA
Ta=25°C, 30ms Pulse
800
1000
TEST CONDITIONS
VIN=5.3V,IOUT=10mA,
TJ=25°C
VIN=4.75 to 10V
LD1117 : IOUT=0 ~ 800mA
LD1117A : IOUT=0 ~ 1.0A
VIN=4.75 to 15V, IOUT=0mA
VIN=4.75V
LD1117 : IOUT=0 ~ 800mA
LD1117A : IOUT=0 ~ 1000mA
VIN=8V, TJ =25°C
60
V
V
mA
100
μV
75
dB
1.10
1.25
1.30
1.30
0.10
V
V
V
V
%/W
TYP.
3.300
3.300
MAX.
3.333
3.365
UNIT
1%
2%
MIN.
3.267
3.235
2%
3.235
3.300
3.365
4%
3.160
3.300
3.440
1
6
mV
1
10
mV
15
10
%
%
V
mA
LD1117
LD1117A
B=10Hz to 10KHz, TJ =25°C
IOUT=40mA, f=120Hz, TJ =25°C,
VIN=6.3V, VRIPPLE=1Vpp
IOUT=100mA
IOUT=500mA
IOUT=800mA
IOUT=1000 mA
Ta=25°C, 30ms Pulse
VIN=8.3V, TJ =25°C
UNIT
1.00
1.15
1.20
1.20
0.01
0.5
0.3
1000 hrs, TJ =125°C
IOUT=100mA
VIN≤15V
UNISONIC TECHNOLOGIES CO., LTD
www.unisonic.com.tw
1%
2%
5
800
1000
60
V
V
mA
100
μV
75
dB
1.00
1.15
1.20
1.20
0.01
1.10
1.25
1.30
1.30
0.10
V
V
V
V
%/W
7 of 12
QW-R102-006,Q
LD1117/A
„
LINEAR INTEGRATED CIRCUIT
ELECTRICAL CHARACTERISTICS(Cont.)
For LD1117/A-3.6
PARAMETER
SYMBOL
Output Voltage
VOUT
Output Voltage
VOUT
Line Regulation
ΔVOUT
Load Regulation
ΔVOUT
Temperature stability
Long Term Stability
Operating Input Voltage
Quiescent Current
ΔVOUT
ΔVOUT
VIN
IQ
Current Limit
ILIMIT
Output Noise Voltage
Supply Voltage Rejection
eN
SVR
Dropout Voltage
VD
Thermal Regulation
For LD1117/A-5.0
PARAMETER
SYMBOL
Output Voltage
VOUT
Output Voltage
VOUT
Line Regulation
ΔVOUT
Load Regulation
ΔVOUT
Temperature stability
Long Term Stability
Operating Input Voltage
Quiescent Current
ΔVOUT
ΔVOUT
VIN
IQ
Current Limit
ILIMIT
Output Noise Voltage
Supply Voltage Rejection
eN
SVR
Dropout Voltage
Thermal Regulation
VD
TEST CONDITIONS
VIN=5.6V, IOUT=10mA, TJ =25°C
VIN=5 to 10V
LD1117 : IOUT=0 ~ 800mA
LD1117A : IOUT=0 ~ 1.0A
VIN=5 to 15V, IOUT=0mA
VIN=5V
LD1117 : IOUT=0 ~ 800mA
LD1117A : IOUT=0 ~ 1000mA
TYP.
3.600
MAX.
3.636
UNIT
3.528
3.600
3.672
V
1
6
mV
1
10
mV
15
10
%
%
V
mA
0.5
0.3
1000 hrs, TJ =125°C
IOUT=100mA
VIN≤15V
5
LD1117
LD1117A
B=10Hz to 10KHz, TJ =25°C
IOUT=40mA, f=120Hz, TJ =25°C,
VIN=6.6V, VRIPPLE=1Vpp
IOUT=100mA
IOUT=500mA
IOUT=800mA
IOUT=1000 mA
Ta=25°C, 30ms Pulse
VIN=8.6V, Tj=25°C
TEST CONDITIONS
VIN=7V,IOUT=10mA, TJ =25°C
VIN=6.5 to 15V
LD1117 : IOUT=0 ~ 800mA
LD1117A : IOUT=0 ~ 1.0A
VIN=6.5 to 15V, IOUT=0mA
VIN=6.5V
LD1117 : IOUT=0 ~ 800mA
LD1117A : IOUT=0 ~ 1000mA
800
1000
60
mA
100
μV
75
dB
1.00
1.15
1.20
1.20
0.01
1.10
1.25
1.30
1.30
0.10
V
V
V
V
%/W
UNIT
MIN.
4.950
4.900
TYP.
5.000
5.000
MAX.
5.050
5.100
2%
4.900
5.000
5.100
4%
4.800
5.000
5.200
1
6
mV
1
10
mV
15
10
%
%
V
mA
LD1117
LD1117A
B=10Hz to 10KHz, TJ =25°C
IOUT=40mA, f=120Hz, TJ =25°C,
VIN=8V, VRIPPLE=1Vpp
IOUT=100mA
IOUT=500mA
IOUT=800mA
IOUT=1000 mA
Ta=25°C, 30ms Pulse
VIN=10V, TJ =25°C
V
1%
2%
0.5
0.3
1000 hrs, TJ =125°C
IOUT=100mA
VIN≤15V
UNISONIC TECHNOLOGIES CO., LTD
www.unisonic.com.tw
MIN.
3.564
5
800
1000
60
V
V
mA
100
μV
75
dB
1.00
1.15
1.20
1.20
0.01
1.10
1.25
1.30
1.30
0.10
V
V
V
V
%/W
8 of 12
QW-R102-006,Q
LD1117/A
„
LINEAR INTEGRATED CIRCUIT
ELECTRICAL CHARACTERISTICS(Cont.)
For LD1117/A-ADJUSTABLE
PARAMETER
Reference Voltage
SYMBOL
TEST CONDITIONS
VREF VIN-VOUT=2V, IOUT=10mA, TJ =25°C
VIN-VOUT=1.4 to 10V
Reference Voltage
VREF LD1117 : IOUT=10 ~ 800mA
LD1117A : IOUT=10 ~ 1000mA
Line Regulation
ΔVOUT VIN-VOUT=1.5 to 13.75V, IOUT=10mA
VIN-VOUT=3V
Load Regulation
ΔVOUT LD1117 : IOUT=10 ~ 800mA
LD1117A : IOUT=10 ~ 1000mA
Temperature stability
ΔVOUT
Long Term Stability
ΔVOUT 1000 hrs, TJ =125°C
Operating Input Voltage
VIN
Adjustment Pin Current
IADJ
VIN≤15V
VIN-VOUT=1.4 to 10V,
Adjustment Pin Current Change
ΔIADJ LD1117 : IOUT=10 ~ 800mA
LD1117A : IOUT=10 ~ 1000mA
Minimum Load Current
IO(MIN) VIN=15V
LD1117
Current Limit
ILIMIT VIN-VOUT=5V, TJ =25°C
LD1117A
Output Noise (%Vo)
eN
B=10Hz to 10KHz, TJ =25°C
IOUT=40mA, f=120Hz, TJ =25°C,
Supply Voltage Rejection
SVR
VIN-VOUT=3V, Vripple=1Vpp
IOUT=100mA
IOUT=500mA
Dropout Voltage
VD
IOUT=800mA
IOUT=1000mA
Thermal Regulation
Ta=25°C, 30ms Pulse
„
MIN
1.238
TYP
1.25
MAX
1.262
UNIT
V
1.275
V
0.035
0.200
%
0.10
0.400
%
60
15
120
%
%
V
μA
1
5
μA
2
5
mA
1.225
0.50
0.3
800
1000
60
mA
0.003
%
75
dB
1.00
1.15
1.20
1.20
0.01
1.10
1.25
1.30
1.30
0.10
V
V
V
V
%/W
THERMAL DATA
PARAMETER
Thermal Resistance Junction-Case
Thermal Resistance Junction-Ambient
SOT-223
SYMBOL
RATINGS
15
SOP-8
20
TO-252
12
4
TO-263
SOT-223
SOP-8
TO-252
TO-220
TO-263
4
165
150
112
54
64
UNISONIC TECHNOLOGIES CO., LTD
www.unisonic.com.tw
θJC
TO-220
θJA
UNIT
°C/W
°C/W
9 of 12
QW-R102-006,Q
LD1117/A
„
LINEAR INTEGRATED CIRCUIT
TYPICAL APPLICATIONS
UTC LD1117/A-5.0V
VIN
IN
+
OUT
+
GND
10μF
100μF
VOUT = -5V
Floating Input
FIG.1 Negative Supply
110
110
UTC LD1117/A2.85V
IN
+
4.75V
to
5.25V
GND
110
+
18-27
Lines
22μF
10μF
110
FIG.2 Active Terminator for SCSI-2 BUS
FIG.3 Circuit for Increasing Output Voltage
UNISONIC TECHNOLOGIES CO., LTD
www.unisonic.com.tw
10 of 12
QW-R102-006,Q
LD1117/A
„
LINEAR INTEGRATED CIRCUIT
APPLICATION NOTE of LD1117/A ADJUSTABLE
The LD1117/A ADJUSTABLE has a reference voltage of between the OUT and ADJ pins. IADJ is 60μA typ.
(120μA max.) and ΔIADJ is 1μA typ. (5μA max.).
R1 is normally fixed to 120Ω.
From figure 4 we obtain:
VOUT=VREF+R2(IADJ + IR1)=VREF + R2(IADJ + VREF / R1)=VREF(1+R2/R1) + R2 x IADJ.
Usually R2 value is in the range of few KΩ, so the R2 X IADJ product could be neglected; then the above
expression becomes: VOUT=VREF(1+R2/R1)
For better load regulation, realize a good Kelvin connection of R1 and R2 is important. Particularly R1
connection must be realized very close to OUT and ADJ pin, while R2 ground connection must be placed as
near as possible to the negative Load pin. Ripple rejection can be improved by introducing a 10μF electrolytic
capacitor placed in parallel to the R2 resistor (See Fig. 5)
UTC LD1117/A
VIN
IN
+
OUT
ADJ
10μF
VOUT
+
10μF
R1
120Ω
VREF
R2
FIG.4 Adjustable Output Voltage Application Circuit
FIG.5 Adjustable Output Voltage Application with improved Ripple Rejection.
UNISONIC TECHNOLOGIES CO., LTD
www.unisonic.com.tw
11 of 12
QW-R102-006,Q
LD1117/A
Output Voltage(V)
Reference Voltage (V)
TYPICAL PERFORMANCE CHARACTERISTICS
Power (W)
„
LINEAR INTEGRATED CIRCUIT
UTC assumes no responsibility for equipment failures that result from using products at values that
exceed, even momentarily, rated values (such as maximum ratings, operating condition ranges, or
other parameters) listed in products specifications of any and all UTC products described or contained
herein. UTC products are not designed for use in life support appliances, devices or systems where
malfunction of these products can be reasonably expected to result in personal injury. Reproduction in
whole or in part is prohibited without the prior written consent of the copyright owner. The information
presented in this document does not form part of any quotation or contract, is believed to be accurate
and reliable and may be changed without notice.
UNISONIC TECHNOLOGIES CO., LTD
www.unisonic.com.tw
12 of 12
QW-R102-006,Q
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