UTC LD1985
LINEAR INTEGRATED CIRCUIT
UTC
UNISONIC TECHNOLOGIES CO., LTD.
1
QW-R102-021,B
VERY LOW DROP AND LOW
NOISE VOLTAGE REGULATOR
LOW ESR CAP. COMPATIBLE,
WITH INHIBIT FUNCTION
DESCRIPTION
The UTC LD1985 is a 150mA fixed output voltage
regulator. The ultra low drop voltage and the low
quiescent current make them particularly suitable for low
noise, low power applications, and in battery powered
systems. In sleep mode quiescent current is less than
1A when INHIBIT pin is pulled low. Shutdown Logic
Control Function is available on pin 3 (TTL compatible).
This means that when the device is used as local
regulator, it is possible to put a part of the board in
standby, decreasing the total power consumption.
An external capacitor, C
BYP
=10nF, connected between
bypass pin and GND reduce the noise to 30Vrms.
Typical application are in cellular phone, palmtop
laptop computer, personal digital assistant (PDA),
personal stereo, camcorder and camera.
FEATURES
*VERY LOW DROPOUT VOLTAGE (280mV at 150mA
AND 7mV at 1mA LOAD)
*VERY LOW QUIESCENT CURRENT (2mA Typ. at
150mA LOAD AND 80A at NO LOAD)
*OUTPUT CURRENT UP TO 150mA
*LOGIC CONTROLLED ELECTRONIC SHUTDOWN
*OUTPUT VOLTAGE OF 1.5, 1.8, 2.5, 2.8, 2.85, 3, 3.1,
3.2, 3.3, 3.5, 3.6, 3.8, 4, 4.7, 5V
*INTERNAL CURRENT AND THERMAL LIMIT
*AVAILABLE IN 1% TOLLERANCE (at 25, A
VERSION)
*LOW OUTPUT NOISE VOLTAGE 30Vrms
SOT-25
1
2
3
4
5
1:V
IN
2:GND 3:INHIBIT
4:Bypass 5:V
OUT
PIN DESCRIPTION
PIN
NO.
PIN
NAME
FUNCTION
1 IN
Input
Port
2 GND
Ground
Pin
3 INHIBIT
Control switch ON/OFF.
Inhibit is not internally
pulled-up; it cannot be left
floating. Disable the device
when connected to GND or
to a positive voltage less
than 0.18V
4 Bypass
Bypass Pin: Capacitor to
be connected to GND in
order to improve the
thermal noise
performances.
5 OUT
Output
Port
UTC LD1985
LINEAR INTEGRATED CIRCUIT
UTC
UNISONIC TECHNOLOGIES CO., LTD.
2
QW-R102-021,B
MARKING INFORMATION
PART
NUMBER
VOLTAGE
VOLTAGE
CODE
PART
NUMBER
VOLTAGE
VOLTAGE
CODE
MARKING
LD1985-1.5V 1.5V
15 LD1985-3.3V 3.3V
33
LD1985-1.8V 1.8V
18 LD1985-3.5V 3.5V
35
LD1985-2.5V 2.5V
25 LD1985-3.6V 3.6V
36
LD1985-2.8V 2.8V
28 LD1985-3.8V 3.8V
38
LD1985-2.85V 2.85V
2J LD1985-4.0V
4.0V
40
LD1985-3.0V 3.0V
30 LD1985-4.7V 4.7V
47
LD1985-3.1V 3.1V
31 LD1985-5.0V 5.0V
50
LD1985-3.2V 3.2V
32
5
4
3
VOLTAGE
CODE
2
1
L D
BLOCK DIAGRAM
Vout
DRIVER
ERROR
AMPLIFIER
CURRENT
LIMIT
REFERENCE
VOLTAGE
START-UP
SHUTDOWN
TERM. PROTEC.
GND
BYPASS
SHDN
Vin
ABSOLUTE MAXIMUM RATINGS
PARAMETER SYMBOL RATINGS
UNIT
DC Input Voltage
V
i
7
V
INHIBIT Input Voltage
V
INH
7
V
Output Current
I
o
Internally
limited
Power Dissipation
P
tot
Internally
limited
Storage Temperature Range
T
stg
-65 ~ +150
Operating Junction Temperature Range
T
op
-40 ~ +125
THERMAL DATA
PARAMETER SYMBOL
RATINGS
UNIT
Thermal Resistance Junction-case
R
thj-case
81
/W
UTC LD1985
LINEAR INTEGRATED CIRCUIT
UTC
UNISONIC TECHNOLOGIES CO., LTD.
3
QW-R102-021,B
ELECTRICAL CHARACTERISTICS FOR LD1985 V
O
1.0%
(T
J
=25, V
i
=Vo+1V, Io=1mA, V
SHDN
=2V, C
i
=1F, Co=1F, unless otherwise specified)
PARAMETER SYMBOL TEST
CONDITIONS MIN
TYP
MAX
UNIT
Operating Input Voltage
Vop
2.5
7
V
V
i
=2.5V 1.485
1.5
1.515
V
Io=1 ~ 150mA
1.462
1.538
V
Output Voltage
Vo
Io=1 ~ 150mA, T
J
=-40 ~ 125
1.447 1.553 V
V
i
=2.8V 1.782
1.8
1.818
V
Io=1 ~ 150mA
1.755
1.845
V
Output Voltage
Vo
Io=1 ~ 150mA, T
J
=-40 ~ 125
1.737 1.863 V
V
i
=3.5V 2.475
2.5
2.525
V
Io=1 ~ 150mA
2.4375
2.5625
V
Output Voltage
Vo
Io=1 ~ 150mA, T
J
=-40 ~ 125
2.4125 2.5875 V
V
i
=3.8V 2.772
2.8
2.828
V
Io=1 ~ 150mA
2.730
2.870
V
Output Voltage
Vo
Io=1 ~ 150mA, T
J
=-40 ~ 125
2.702 2.898 V
V
i
=3.85V 2.821
2.85
2.879
V
Io=1 ~ 150mA
2.778
2.921
V
Output Voltage
Vo
Io=1 ~ 150mA, T
J
=-40 ~ 125
2.750 2.950 V
V
i
=4.0V 2.970
3.0
3.030
V
Io=1 ~ 150mA
2.925
3.075
V
Output Voltage
Vo
Io=1 ~ 150mA, T
J
=-40 ~ 125
2.895 3.105 V
V
i
=4.1V 3.069
3.1
3.131
V
Io=1 ~ 150mA
3.022
3.1775
V
Output Voltage
Vo
Io=1 ~ 150mA, T
J
=-40 ~ 125
2.9915 3.2085 V
V
i
=4.2V 3.168
3.2
3.232
V
Io=1 ~ 150mA
3.120
3.280
V
Output Voltage
Vo
Io=1 ~ 150mA, T
J
=-40 ~ 125
3.088 3.312 V
V
i
=4.3V 3.267
3.3
3.333
V
Io=1 ~ 150mA
3.2175
3.3825
V
Output Voltage
Vo
Io=1 ~ 150mA, T
J
=-40 ~ 125
3.1845 3.4155 V
V
i
=4.5V 3.465
3.5
3.535
V
Io=1 ~ 150mA
3.412
3.587
V
Output Voltage
Vo
Io=1 ~ 150mA, T
J
=-40 ~ 125
3.377 3.622 V
V
i
=4.6V 3.564
3.6
3.636
V
Io=1 ~ 150mA
3.510
3.690
V
Output Voltage
Vo
Io=1 ~ 150mA, T
J
=-40 ~ 125
3.474 3.726 V
V
i
=4.8V 3.762
3.8
3.838
V
Io=1 ~ 150mA
3.705
3.895
V
Output Voltage
Vo
Io=1 ~ 150mA, T
J
=-40 ~ 125
3.667 3.933 V
V
i
=5.0V 3.96
4
4.04
V
Io=1 ~ 150mA
3.9
4.1
V
Output Voltage
Vo
Io=1 ~ 150mA, T
J
=-40 ~ 125
3.86 4.14 V
V
i
=5.7V 4.653
4.7
4.747
V
Io=1 ~ 150mA
4.582
4.817
V
Output Voltage
Vo
Io=1 ~ 150mA, T
J
=-40 ~ 125
4.5355 4.8645 V
V
i
=6.0V 4.95
5
5.05
V
Io=1 ~ 150mA
4.875
5.125
V
Output Voltage
Vo
Io=1 ~ 150mA, T
J
=-40 ~ 125
4.825 5.175 V
UTC LD1985
LINEAR INTEGRATED CIRCUIT
UTC
UNISONIC TECHNOLOGIES CO., LTD.
5
QW-R102-021,B
ELECTRICAL CHARACTERISTICS FOR LD1985 V
O
1.5%
(T
J
=25, V
i
=Vo+1V, Io=1mA, V
SHDN
=2V, C
i
=1F, Co=1F, unless otherwise specified)
PARAMETER SYMBOL TEST
CONDITIONS MIN
TYP
MAX
UNIT
Operating Input Voltage
Vop
2.5
7
V
V
i
=2.5V 1.477
1.5
1.523
V
Io=1 ~ 150mA
1.455
1.545
V
Output Voltage
Vo
Io=1 ~ 150mA, T
J
=-40 ~ 125
1.440 1.560 V
V
i
=2.8V 1.773
1.8
1.827
V
Io=1 ~ 150mA
1.746
1.854
V
Output Voltage
Vo
Io=1 ~ 150mA, T
J
=-40 ~ 125
1.728 1.872 V
V
i
=3.5V 2.4625
2.5
2.5375
V
Io=1 ~ 150mA
2.425
2.575
V
Output Voltage
Vo
Io=1 ~ 150mA, T
J
=-40 ~ 125
2.4 2.6 V
V
i
=3.8V 2.758
2.8
2.842
V
Io=1 ~ 150mA
2.716
2.884
V
Output Voltage
Vo
Io=1 ~ 150mA, T
J
=-40 ~ 125
2.688 2.912 V
V
i
=3.85V 2.807
2.85
2.893
V
Io=1 ~ 150mA
2.764
2.935
V
Output Voltage
Vo
Io=1 ~ 150mA, T
J
=-40 ~ 125
2.736 2.964 V
V
i
=4.0V 2.955
3.0
3.045
V
Io=1 ~ 150mA
2.91
3.09
V
Output Voltage
Vo
Io=1 ~ 150mA, T
J
=-40 ~ 125
2.88 3.12 V
V
i
=4.1V 3.0535
3.1
3.1465
V
Io=1 ~ 150mA
3.007
3.193
V
Output Voltage
Vo
Io=1 ~ 150mA, T
J
=-40 ~ 125
2.976 3.224 V
V
i
=4.2V 3.152
3.2
3.248
V
Io=1 ~ 150mA
3.104
3.296
V
Output Voltage
Vo
Io=1 ~ 150mA, T
J
=-40 ~ 125
3.072 3.328 V
V
i
=4.3V 3.2505
3.3
3.3495
V
Io=1 ~ 150mA
3.201
3.399
V
Output Voltage
Vo
Io=1 ~ 150mA, T
J
=-40 ~ 125
3.168 3.432 V
V
i
=4.5V 3.447
3.5
3.552
V
Io=1 ~ 150mA
3.395
3.605
V
Output Voltage
Vo
Io=1 ~ 150mA, T
J
=-40 ~ 125
3.360 3.640 V
V
i
=4.6V 3.546
3.6
3.654
V
Io=1 ~ 150mA
3.492
3.708
V
Output Voltage
Vo
Io=1 ~ 150mA, T
J
=-40 ~ 125
3.456 3.744 V
V
i
=4.8V 3.743
3.8
3.857
V
Io=1 ~ 150mA
3.686
3.914
V
Output Voltage
Vo
Io=1 ~ 150mA, T
J
=-40 ~ 125
3.648 3.952 V
V
i
=5.0V 3.94
4
4.06
V
Io=1 ~ 150mA
3.88
4.12
V
Output Voltage
Vo
Io=1 ~ 150mA, T
J
=-40 ~ 125
3.84 4.16 V
V
i
=5.7V 4.6295
4.7
4.7705
V
Io=1 ~ 150mA
4.559
4.841
V
Output Voltage
Vo
Io=1 ~ 150mA, T
J
=-40 ~ 125
4.512
4.888
V
V
i
=6.0V 4.925
5
5.075
V
Output Voltage
Vo
Io=1 ~ 150mA
4.85
5.15
V
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