UTC LD3870
LINEAR INTEGRATED CIRCUIT
UTC
UNISONIC TECHNOLOGIES CO., LTD.
1
QW-R102-027,B
LOW DROPOUT VOLTAGE
REGULATOR
DESCRIPTION
The UTC LD3870 is low dropout voltage regulator
designed for cellular phone application.
FEATURES
* High Ripple Rejection: 56dB
RR(DC<f<60kHz)
66dB typ. (f=100Hz)
60dB typ. (f=1kHz)
* Output Noise Voltage: Vno=30
V , Cp=0.01
F
* Output Current: Io(max)=150mA
* High Precision Output: Vo
2%
* Low Dropout Voltage:
V
l
-o=0.12V typ.
(Io=60mA,Vo
1.8V)
* Input Voltage range: +2~+14V(Vo=1.5V Version)
* ON/OFF Control: Active High
* Output capacitor with 4.7uF ceramic capacitor
* Internal Short Circuit Current Limit
* Internal Thermal Overload Protection
SOT-25
1
2
3
4
5
1:CONTROL(Active High) 2:GND
3:NOISE BYPASS 4:V
OUT
5: V
IN
MARKING INFORMATION
PART
NUMBER
VOLTAGE
VOLATGE
CODE
PART
NUMBER
VOLTAGE
VOLATGE
CODE
MARKING
LD3870-1.5V 1.5V
15 LD3870-3.1V
3.1V
31
LD3870-1.8V 1.8V
18 LD370-3.2V
3.2V
32
LD3870-1.9V 1.9V
19 LD3870-3.3V
3.3V
33
LD3870-2.0V 2.0V
20 LD3870-3.4V
3.4V
34
LD3870-2.1V 2.1V
21 LD3870-3.5V
3.5V
35
LD3870-2.3V 2.3V
23 LD3870-3.6V
3.6V
36
LD3870-2.4V 2.4V
24 LD3870-3.8V
3.8V
38
LD3870-2.5V 2.5V
25 LD3870-4.0V
4.0V
40
LD3870-2.6V 2.6V
26 LD3870-4.5V
4.5V
45
LD3870-2.7V 2.7V
27 LD3870-4.6V
4.6V
46
LD3870-2.8V 2.8V
28 LD3870-4.7V
4.7V
47
LD3870-2.85V 2.85V
2J
LD3870-4.8V
4.8V
48
LD3870-2.9V 2.9V
29 LD3870-5.0V
5.0V
50
LD3870-3.0V 3.0V
30
5
4
3
VOLTAGE
CODE
2
1
M B
UTC LD3870
LINEAR INTEGRATED CIRCUIT
UTC
UNISONIC TECHNOLOGIES CO., LTD.
2
QW-R102-027,B
BLOCK DAGRAM
+
-
V
IN
Cont
GND
Bandgap
Reference
Thermal
Protection
V
OUT
Noise
Bypass
ABSOLUTE MAXIMUM RATINGS
(Ta=25
)
PARAMETER SYMBOL
RATINGS
UNIT
Input Voltage
V
IN
+14
V
Control Voltage
V
CONT
+14(Note
1)
V
Power Dissipation
P
D
200
mW
Operating Temperature
Topr
-40 ~ +85
Storage Temperature
Tstg
-40 ~ +125
Note 1: When input voltage is less than +14V,the absolute maximum control voltage is equal to the input voltage.
ELECTRICAL CHARACTERISTICS
(V
IN
=Vo+1V, C
IN
=0.1
F, Co=4.7
F, Cp=0.01
F, Ta=25
)
PARAMETER SYMBOL TEST
CONDITONS MIN.
TYP.
MAX.
UNIT
Output Voltage
Vo
Io=30mA
-2%
+2%
V
Quiescent Current
I
Q
Io=0mA, expect lcont
200
300
A
Quiescent Current
At Control OFF
I
Q(OFF)
V
CONT
=0V
100 nA
Output Current
Io
Vo-0.3V
150
200
mA
Line Regulation
Vo/
V
IN
V
IN
=Vo+1V ~ Vo+6V, Io=30mA
0.10
%/V
Load Regulation
Vo/
Io Io=0 ~ 100mA
0.03
%/mA
Dropout Voltage
V
I
-o
Io=60mA
0.12
0.2
V
Ripple Rejection
RR
ein=200mVrms, f=1kHz, Io=10mA,
V
IN
=Vo+2V,
Vo=3V Version
60 dB
Average Temperature
Coefficient of Output Voltage
Vo/
Ta
Ta=0~85
, Io=10mA,
Vo=3V Version
0.2
mV/
Output Noise Voltage
V
NO
f=10Hz ~ 80kHz, Io=10mA,
Vo=3V Version
30
Vrms
Control Voltage for ON-state
V
CONT(ON)
1.6
V
Control Voltage for OFF-state V
CONT(OFF)
0.6
V
Note 2: The above specification is a common specification for all output voltages.Therefore, it may be different from
the individual specification for a specific output voltage.
UTC LD3870
LINEAR INTEGRATED CIRCUIT
UTC
UNISONIC TECHNOLOGIES CO., LTD.
3
QW-R102-027,B
ELECTRICAL CHARACTERISTICS
(Vo=1.5V Version, V
IN
=2.4V, C
IN
=0.1
F, Co=4.7
F, Cp=0.01
F, Ta=25
)
PARAMETER SYMBOL
TEST
CONDITONS MIN.
TYP.
MAX.
UNIT
Output Voltage
Vo
Io=30mA
-2%
+2%
V
Quiescent Current
I
Q
Io=0mA, expect Icont
200
300
A
Quiescent Curretn
At Control OFF
I
Q(OFF)
V
CONT
=0V
100 nA
Output Curretn
Io
Vo-0.3V
150
200
mA
Line Regulation
Vo/
V
IN
V
IN
=Vo+1V ~ Vo+6V, Io=30mA
0.10
%/V
Load Regulation
Vo/
Io Io=0 ~ 100mA
0.03
%/mA
Ripple Rejection
RR
ein=200mVrms, f=1kHz, Io=10mA,
V
IN
=Vo+2V
64 dB
Average Temperature
Coefficient of Output Voltage
Vo/
Ta
Ta=0 ~ 85
, Io=10mA
0.13 mV/
Output Noise Voltage
V
NO
f=10Hz ~ 80kHz, Io=10mA
15
Vrms
Control Voltage for ON-state
V
CONT(ON)
1.6
V
Control Voltage for OFF-state
V
CONT(OFF)
0.6
V
TEST CIRCUIT
V
IN
V
OUT
CONTROL
NOISE
BYPASS
GND
A
A
V
V
I
IN
V
IN
V
CONT
I
CONT
I
OUT
V
OUT
(tantalum)
4.7
F
+
+
C
P
=0.01
F
0.1
F
UTC LD3870
TYPICAL APPLICATON
In case that ON/OFF Control is not required:
V
IN
V
OUT
CONTROL
NOISE
BYPASS
GND
(ceramic or tantalum)
(0~300k
)
R
V
OUT
0.1
F
Cp=0.01
F
4.7
F
UTC LD3870
UTC LD3870
LINEAR INTEGRATED CIRCUIT
UTC
UNISONIC TECHNOLOGIES CO., LTD.
4
QW-R102-027,B
Connect control terminal to V
IN
terminal
The quiescent current can be reduced by using a resistance "R". Instead, it increases the minimum operating voltage.
For further information, please refer to Figure "Output Voltage vs. Control Voltage".
In use of ON/OFF CONTROL:
V
IN
V
OUT
CONTROL
NOISE
BYPASS
GND
(ceramic or tantalum)
R
V
OUT
V
IN
UTC LD3870
4.7
F
Cp=0.01
F
0.1
F
State of control terminal:
* "H" Output is enables.
* "L"or "open" Output is disabled.
* Noise bypass Capacitance Cp
Noise bypass capacitance Cp reduces noise generated by hand-gap reference circuit.
Noise level and ripple rejection will be improved when larger Cp is used.
Use of smaller Cp value may cause oscillation.
Use the Cp value of 0.01uF greater to avoid the problem.
UTC LD3870
LINEAR INTEGRATED CIRCUIT
UTC
UNISONIC TECHNOLOGIES CO., LTD.
5
QW-R102-027,B
TYPICAL CHARACTERISTICS
3
3.2
2.7
2.8
2.7
3.4
2.9
2.8
3.1
3
2.9
LD3870-3.0V
Output Voltage vs.Input Voltage
O
u
t
put
put
Volt
age,
Vo (V)
3.1
3.2
3.3
Input Voltage, V
IN
(V)
@:Ta=25
Co=4.7
F(tantalum)
Cp=0.01
F
Io=0A
Io=30mA
Io=100mA
3
3.5
0
50
0
300
2.5
2
150
100
LD3870-3.0V
Output Voltage vs.Output current
O
u
t
put
put
Volt
age,
Vo (V)
4
200
250
Output current, Io (mA)
1.5
1
0.5
@:Ta=25
VIN=4V
CL=4.7
F(tantalum)
Cp=0.01
F
10
20
0
50
0
5
150
100
LD3870-3.0V
Ground Pin Current vs.Output Current
G
r
ound Pin Current
,
I
GND
(mA)
15
200
Output current, Io (mA)
0.2
0.3
0
50
0
0.15
150
100
Dropout
Volt
age,
dV
I-0
(V)
0.25
200
Output current, Io (mA)
LD3870-3.0V
Output Voltage vs.Output current
0.1
0.05
40
60
0
0.5
0
30
1.5
1
Cont
rol Current
,
I
c
ont
(A)
50
3.5
Control Voltage, Vcont (V)
LD3870-3.0V
Control Current vs. Control Voltage
20
10
3
2.5
2
4
3
3.5
0
0.5
0
3
2.5
2
1.5
1
LD3870-3.0V
Output Voltage vs.Control Voltage
O
u
t
put
put
Volt
age,
Vo (V)
4
2
2.5
Control Voltage, Vcont (V)
1.5
1
0.5
@:Ta=25
VIN=4V
CL=4.7
F(tantalum)
Cp=0.01
F
@:Ta=25
CL=4.7
F(tantalum)
Cp=0.01
F
Rc=50k
Rc=0
Rc=100k
@:Ta=25
VIN=4V
CL=4.7
F(tantalum)
Cp=0.01
F
Io=30mA
Rc=50k
Rc=0
Rc=100k
@: VIN=4V
Ta=25
CL=4.7
F
Cp=0.01
F
Io=30mA
UTC LD3870
LINEAR INTEGRATED CIRCUIT
UTC
UNISONIC TECHNOLOGIES CO., LTD.
6
QW-R102-027,B
200
300
0
10p
1p
150
1000p
100p
O
u
t
put
Noise Volt
age,
Vn (Vrms)
250
0.01u
Noise Bypass Capacitor, Cp (F)
LD3870-3.0V
Output Noise Voltage vs.Noise Bypass Capacitor
100
50
0.1u
60
100
0
0.01
0.001
1
0.1
O
u
t
put
Noise Volt
age,
Vn (Vrms)
80
10
Output Current, Io (mA)
LD3870-3.0V
Output Noise Voltage vs.Noise Output Current
40
20
100
70
80
30
100
10
60
1K
Ripple Reject
ion,
RR (dB)
10K
Frequency, f (Hz)
LD3870-3.0V
Ripple Rejection vs.Frequency
50
40
100K
70
80
30
0.01
0.001
60
0.1
Ripple Reject
ion,
RR (dB)
1
Output Current, Io (mA)
LD3870-3.0V
Ripple Rejection vs.Output Current
50
40
10
100
10
100
10
10
1
100
Equivalent
Serise Resist
ance,
ESR (
)
Output Current, Io (mA)
LD3870-3.0V
Equivalent Serise Resistance vs.Output Current
0.1
0.02
1m
10m
CL=1
F(Ceramic)
CL=4.7
F(Ceramic)
@:Ta=25
VIN=4V
Io=10mA
CL=2.2
F(Ceramic)
CL=1
F(Ceramic)
@:Ta=25
VIN=4V
Cp=0.01
F
@:Ta=25
VIN=4V
CL=1
F(Ceramic)
Cp=0.01
F
Oscillation Free
100m
Io=30mA
Io=0mA
Io=10mA
@:Ta=25
VIN=4V
ein=200mVrms
CL=1
F
Cp=0.01
F
f=10KHz
f=1KHz
@:Ta=25
VIN=5V
ein=200mVrms
CL=1
F
Cp=0.01
F
UTC LD3870
LINEAR INTEGRATED CIRCUIT
UTC
UNISONIC TECHNOLOGIES CO., LTD.
7
QW-R102-027,B
0.2
0.3
0
50
-50
0.15
150
100
Dropout
Volt
age,
dV
I-
0
(V)
0.25
Temperature, Ta (
)
LD3870-3.0V
Dropout Voltage vs.Temperature
0.1
0.05
1
2
0
50
-50
0.5
150
100
LD3870-3.0V
Control Voltage vs.Temperature
Cont
rol Volt
age,
V
CONT(OFF)
(V)
1.5
3
3.5
0
2.5
2
LD3870-3.0V
Output Voltage vs.Output current
O
u
t
put
put
Volt
age,
Vo (V)
4
1.5
1
0.5
200
300
0
50
-50
150
150
100
Qu
i
e
sce
n
t
C
u
rre
n
t, I
Q
(A)
250
LD3870-3.0V
Quiescent Current vs.Temperature
100
50
0
Temperature, Ta (
)
0
Temperature, Ta (
)
Temperature, Ta (
)
0
@:VIN=4V
Output is open
CL=4.7
F(tantalum)
Cp=0.01
F
@:VIN=4V
Output is open
CL=4.7
F(tantalum)
Cp=0.01
F
@: VIN=4V
Io=30mA
C
J
=4.7
F(tantalum)
Cp=0.01
F
@:VIN=4V
Output is open
C
J
=4.7
F(tantalum)
Cp=0.01
F
including lcont
50
-50
150
100
0
200
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.
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