UTC LD3870
LINEAR INTEGRATED CIRCUIT
LOW DROPOUT VOLTAGE
REGULATOR
DESCRIPTION
The UTC LD3870 is low dropout voltage regulator
designed for cellular phone application.
1
2
3
FEATURES
* High Ripple Rejection: 56dB≤RR(DC<f<60kHz)
66dB typ. (f=100Hz)
60dB typ. (f=1kHz)
* Output Noise Voltage: Vno=30ΜV , Cp=0.01μF
* 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
5
4
SOT-25
1:CONTROL(Active High)
3:NOISE BYPASS
4:V
OUT
2:GND
5: V
IN
MARKING INFORMATION
PART
NUMBER
LD3870-1.5V
LD3870-1.8V
LD3870-1.9V
LD3870-2.0V
LD3870-2.1V
LD3870-2.3V
LD3870-2.4V
LD3870-2.5V
LD3870-2.6V
LD3870-2.7V
LD3870-2.8V
LD3870-2.85V
LD3870-2.9V
LD3870-3.0V
VOLTAGE
1.5V
1.8V
1.9V
2.0V
2.1V
2.3V
2.4V
2.5V
2.6V
2.7V
2.8V
2.85V
2.9V
3.0V
VOLATGE
CODE
15
18
19
20
21
23
24
25
26
27
28
2J
29
30
PART
NUMBER
LD3870-3.1V
LD370-3.2V
LD3870-3.3V
LD3870-3.4V
LD3870-3.5V
LD3870-3.6V
LD3870-3.8V
LD3870-4.0V
LD3870-4.5V
LD3870-4.6V
LD3870-4.7V
LD3870-4.8V
LD3870-5.0V
VOLTAGE
3.1V
3.2V
3.3V
3.4V
3.5V
3.6V
3.8V
4.0V
4.5V
4.6V
4.7V
4.8V
5.0V
VOLATGE
CODE
31
32
33
34
35
36
38
40
45
46
47
48
50
MARKING
3
2
1
MB
VOLTAGE
CODE
4
5
UTC
UNISONIC
TECHNOLOGIES
CO., LTD.
1
QW-R102-027,B
UTC LD3870
BLOCK DAGRAM
V
IN
Cont
LINEAR INTEGRATED CIRCUIT
V
OUT
Thermal
Protection
Noise
Bypass
Bandgap
Reference
+
-
GND
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
=0.1μF, Co=4.7μF, Cp=0.01μF, Ta=25℃)
PARAMETER
Output Voltage
Quiescent Current
Quiescent Current
At Control OFF
Output Current
Line Regulation
Load Regulation
Dropout Voltage
Ripple Rejection
SYMBOL
Vo
I
Q
I
Q(OFF)
TEST CONDITONS
Io=30mA
Io=0mA, expect lcont
V
CONT
=0V
MIN.
-2%
TYP.
200
MAX.
+2%
300
100
UNIT
V
μA
nA
mA
%/V
%/mA
Io
Vo-0.3V
△Vo/△V
IN
V
IN
=Vo+1V ~ Vo+6V, Io=30mA
△Vo/△Io
Io=0 ~ 100mA
△V
I
-o
150
200
0.10
0.03
Io=60mA
0.12
0.2
V
ein=200mVrms, f=1kHz, Io=10mA,
RR
60
dB
V
IN
=Vo+2V,
Vo=3V Version
Ta=0~85℃, Io=10mA,
Average Temperature
△Vo/△Ta
mV/℃
0.2
Coefficient of Output Voltage
Vo=3V Version
Output Noise Voltage
f=10Hz ~ 80kHz, Io=10mA,
μVrms
V
NO
30
Vo=3V Version
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
UNISONIC
TECHNOLOGIES
CO., LTD.
2
QW-R102-027,B
UTC LD3870
PARAMETER
Output Voltage
Quiescent Current
Quiescent Curretn
At Control OFF
Output Curretn
Line Regulation
Load Regulation
Ripple Rejection
Average Temperature
Coefficient of Output Voltage
Output Noise Voltage
Control Voltage for ON-state
Control Voltage for OFF-state
LINEAR INTEGRATED CIRCUIT
SYMBOL
Vo
I
Q
I
Q(OFF)
ELECTRICAL CHARACTERISTICS
(Vo=1.5V Version, V
IN
=2.4V, C
IN
=0.1μF, Co=4.7μF, Cp=0.01μF, Ta=25℃)
TEST CONDITONS
Io=30mA
Io=0mA, expect Icont
V
CONT
=0V
MIN.
-2%
TYP.
200
MAX.
+2%
300
100
UNIT
V
μA
nA
mA
%/V
%/mA
dB
mV/℃
μVrms
Io
Vo-0.3V
△Vo/△V
IN
V
IN
=Vo+1V ~ Vo+6V, Io=30mA
△Vo/△Io
Io=0 ~ 100mA
ein=200mVrms, f=1kHz, Io=10mA,
RR
V
IN
=Vo+2V
Ta=0 ~ 85℃, Io=10mA
△Vo/△Ta
V
NO
V
CONT(ON)
V
CONT(OFF)
f=10Hz ~ 80kHz, Io=10mA
150
200
0.10
0.03
64
0.13
15
1.6
0.6
V
V
TEST CIRCUIT
A
V
IN
I
IN
V
IN
V
OUT
+
0.1
μF
+
UTC LD3870
NOISE
BYPASS
C
P
=0.01
μF
4.7
μF
(tantalum)
I
OUT
V
V
OUT
A
I
CONT
CONTROL
GND
V
V
CONT
TYPICAL APPLICATON
①
In case that ON/OFF Control is not required:
V
IN
0.1
μF
V
OUT
V
OUT
4.7
μF
(ceramic or tantalum)
UTC LD3870
R
(0~300kΩ)
CONTROL
GND
NOISE
BYPASS
Cp=0.01
μF
UTC
UNISONIC
TECHNOLOGIES
CO., LTD.
3
QW-R102-027,B
UTC LD3870
②
LINEAR INTEGRATED CIRCUIT
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
0.1
μF
V
IN
V
OUT
V
OUT
4.7
μF
(ceramic or tantalum)
UTC LD3870
R
CONTROL
NOISE
BYPASS
GND
Cp=0.01
μF
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
UNISONIC
TECHNOLOGIES
CO., LTD.
4
QW-R102-027,B
UTC LD3870
3.2
LINEAR INTEGRATED CIRCUIT
LD3870-3.0V
Output Voltage vs.Output current
4
@:Ta=25℃
Co=4.7
μF(tantalum)
Cp=0.01
μ
F
@:Ta=25℃
VIN=4V
CL=4.7
μF(tantalum)
Cp=0.01
μ
F
TYPICAL CHARACTERISTICS
LD3870-3.0V
Output Voltage vs.Input Voltage
3.5
Outputput Voltage, Vo (V)
3
2.5
2
1.5
1
0.5
0
Outputput Voltage, Vo (V)
3.1
Io=0A
3
2.9
Io=30mA
2.8
Io=100mA
2.7
2.7
2.8
2.9
3
3.1 3.2
Input Voltage, V
IN
(V)
3.3
3.4
0
50
200
250
100
150
Output current, Io (mA)
300
LD3870-3.0V
Ground Pin Current vs.Output Current
20
@:Ta=25℃
VIN=4V
CL=4.7
μF(tantalum)
Cp=0.01
μ
F
LD3870-3.0V
Output Voltage vs.Output current
0.3
@:Ta=25℃
CL=4.7
μF(tantalum)
Cp=0.01
μ
F
Ground Pin Current, I
GND
(mA)
0.25
Dropout Voltage, dV
I-0
(V)
0.2
0.15
0.1
0.05
15
10
5
0
0
50
100
150
200
0
0
50
100
150
200
Output current, Io (mA)
LD3870-3.0V
Control Current vs. Control Voltage
60
@:Ta=25℃
VIN=4V
CL=4.7
μF(tantalum)
Cp=0.01
μ
F
Io=30mA
Output current, Io (mA)
LD3870-3.0V
Output Voltage vs.Control Voltage
4
3.5
Outputput Voltage, Vo (V)
3
2.5
2
1.5
1
0.5
4
0
0
0.5
1
1.5
2
2.5
3
@: VIN=4V
Ta=25
℃
CL=4.7
μF
Cp=0.01
μF
Io=30mA
50
Control Current, Icont (µA)
40
30
20
Rc=0Ω
Rc=0Ω
Rc=50kΩ
Rc=100kΩ
Rc=50kΩ
10
0
Rc=100kΩ
0
0.5
1
1.5 2
2.5 3
Control Voltage, Vcont (V)
3.5
Control Voltage, Vcont (V)
UTC
UNISONIC
TECHNOLOGIES
CO., LTD.
5
QW-R102-027,B
