GTM GQ2123

ISSUED DATE :2004/12/16
REVISED DATE :
GQ2123
C M O S P o s i t i v e Vo l t a g e R e g u l a t o r
Description
The GQ2123 series of positive, linear regulators feature low quiescent current (30 A typ.) with low dropout
voltage, making them ideal for battery applications.
These rugged devices have both Thermal Shutdown, and Current Fold-back to prevent device failure under
the “Worst” of operating conditions.
In applications requiring a low noise, regulated supply, place a 1000pF capacitor between Bypass and Ground.
The GQ2123 is stable with an output capacitance of 2.2 F or greater.
Features
Very Low Dropout Voltage
Guaranteed 300mA output
Over-Temperature Shutdown
Current Limiting
Short Circuit Current Fold-back
Highly Accurate± 1.5%
Noise Reduction Bypass Capacitor
Power-saving Shutdown Mode
Factor Pre-set Output Voltage
Functional Block Diagram
Applications
Battery Powered Widgets
Instrumentation
Wireless Devices
PC Peripherals
Portable Electronics
Cordless Phones
Electronic Scales
Package Dimensions
REF.
A
B
C
D
E
F
Millimeter
Min.
Max.
2.70
3.10
2.60
3.00
1.40
1.80
0.30
0.55
0
0.10
0°
10°
REF.
G
H
I
J
K
L
Dimensions
Millimeter
1.90 REF.
1.20 REF.
0.12 REF.
0.37 REF.
0.60 REF.
0.95 REF.
Typical Application Circuit
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ISSUED DATE :2004/12/16
REVISED DATE :
Absolute Maximum Ratings
Parameter
Symbol
Ratings
Unit
Input Max Voltage
VIN
8
V
Output Current
IOUT
PD/( VIN- VO)
mA
Output Voltage
VOUT
1.5~5.0
V
Operating Ambient Temperature
Topr
-40 ~ +85
Junction Temperature
Maximum Junction Temperature
Power Dissipation( T=100 )
Tj
-40 ~ +125
Tj Max
150
PD
380
EDS Classification
Electrical Characteristics Ta=25
Parameter
Output Voltage
Output Current
Current Limit
Load Regulation
Dropout Voltage
unless otherwise noted
Symbol
Condition
Min
VOUT (E)
VIN=VOUT(T)+2V, IO=1mA
-1.5%
Over Temperature Shutdown
Over Temperature Hysterisis
Output Voltage
Temperature Coefficient
Short Circuit Current(Note4)
Power Supply Rejection
Output Voltage Noise
EN Input Threshold
EN Input Bias Current
Shutdown Supply Current
Shutdown Output Voltage
Unit
VOUT(T)
V
2.5%
V
-
mA
VIN=VOUT(T)+2V, IO=300mA
-2.5%
IO
ILIM
VIN=VOUT(T)+2V, VOUT VOUT(E)*0.96
300
-
VIN=VOUT(T)+2V, VO>1.2V
300
450
-
mA
REGLOAD
VIN=VOUT(T)+2V, IO=1mA to 300mA
-1
0.2
1
%
-
-
1300
VDROPOUT
1.2V VOUT(T) 2.0V
IO=300mA
VO=VOUT(E)-2% 2.0V<VOUT(T) 2.8V
-
-
400
-
-
300
-
30
50
A
-
35
-
A
IQ
VIN= VOUT(T)+1V, IO=0mA
IGND
VIN= VOUT(T)+2V, IO=1mA~300mA
REGLINE
1.4V
IO=1mA
VIN=VOUT(T)+1 to 1.4V<VOUT(T) 2.0V
VOUT(T)+2
2.0V<VOUT(T)<4
4.0V VOUT(T)
Input Voltage
Max
1.5%
(Note1)
1.2V VOUT(T)
Line Regulation
TYP
(Note2)
2.8V<VOUT(T)
Quiescent Current
Ground Pin Current
mW
B
-0.2
-
0.2
-0.15
-
0.15
-0.1
0.02
0.1
-0.4
0.2
0.4
mV
%
VIN
OTS
OTH
Note3
-
7
-
150
-
-
30
-
TC
-
30
-
VIN=VOUT(T)+1V, VOUT<0.8V
-
150
300
f=100Hz
-
60
-
f=1kHz
-
50
-
-
20
-
-
30
-
Vrms
2.0
-
VIN
V
VIN=2.7V to 7V
0
-
0.4
V
ISC
PSRR
eN
VEH
VEL
IEH
IEL
ISD
VO,SD
Io=100mA
Co=2.2 F
f=10kHz
f=10Hz~100kHz
Co=2.2 F
Io=10mA
VIN=2.7V to 7V
V
ppm/
mA
dB
VEN=VIN, VIN=2.7V to 7V
-
-
0.1
A
VEN= 0V, VIN=2.7V to 7V
-
-
0.5
A
VIN=5V, VO=0V, VEN<VEL
-
0.5
1
A
Io=0.4mA, VEN<VEL
0
-
0.4
V
Note 1: VOUT (E) =Effective Output Voltage (i.e. the output voltage when “VOUT (T) + 2.0V” is provided at the VIN pin while maintaining a
certain IOUT value).
2: VOUT (T) =Specified Output Voltage
3: VIN (MIN) =VOUT+VDROPOUT
4: To prevent the Short Circuit Current protection feature from being prematurely activated, the input voltage must be applied before
a current source load is applied.
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ISSUED DATE :2004/12/16
REVISED DATE :
Ordering Information ( contd. )
Part Number
GQ2123-15
GQ2123-25
GQ2123-28
GQ2123-30
GQ2123-33
GQ2123-35
GQ2123-37
GQ2123-50
Marking
3B152
XXXX
3B252
XXXX
3B282
XXXX
3B302
XXXX
3B332
XXXX
3B352
XXXX
3B372
XXXX
3B502
XXXX
Output Voltage
Part Number
1.5V
GQ2123-18
2.5V
GQ2123-27
2.8V
GQ2123-29
3.0V
GQ2123-31
3.3V
GQ2123-34
3.5V
GQ2123-36
3.7V
GQ2123-38
5.0V
GQ2123-2H
Marking
3B182
XXXX
3B272
XXXX
3B292
XXXX
3B312
XXXX
3B342
XXXX
3B362
XXXX
3B382
XXXX
3B2H2
XXXX
Output Voltage
1.8V
2.7V
2.9V
3.1V
3.4V
3.6V
3.8V
2.85V
Characteristics Curve
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Detailed Description
The GQ2123 series of COMS regulators contain a PMOS pass transistor, voltage reference, error amplifier,
over-current protection, and thermal shutdown.
The P-channel pass transistor receives data from the error amplifier, over-current shutdown, and thermal
protection circuits. During normal operation, the error amplifier compares the output voltage to a precision
reference. Over-current and Thermal shutdown circuits become active when the junction temperature exceeds
150 , or the current exceeds 300mA. During thermal shutdown, the output voltage remains low. Normal
operation is restored when the junction temperature drops below 120 .
The GQ2123 switches from voltage mode to current mode when the load exceeds the rated output current.
This prevents over-stress. The GQ2123 also incorporates current fold-back to reduce power dissipation when
the output is short circuited. This feature becomes active when the output drops below 0.8 volts, and reduces
the current flow by 65%. Full current is restored when the voltage exceeds 0.8 volts.
External Capacitors
The GQ2123 is stable with an output capacitance to ground of 2.2 F or greater. Ceramic capacitors have the
lowest ESR, and will offer the best AC performance. Conversely, Aluminum Electrolytic capacitors exhibit the
highest ESR, resulting in the poorest AC response. Unfortunately, large value ceramic capacitors are
comparatively expensive. One option is to parallel a 0.1 F ceramic capacitor with a 10 F Aluminum Electrolytic.
The benefit is low ESR, high capacitance, and low overall cost.
A second capacitor is recommended between the input and ground to stabilize Vin. The input capacitor should
be at least 0.1 F to have a beneficial effect.
A third capacitor can be connected between the BY-PASS pin and GND. This capacitor can be a low cost
Polyester Film variety between the value of 0.001~0.01 F. A large capacitor improves the AC ripple rejection,
but also makes the output come up slowly. This “Soft” turn-on is desirable in some applications to limit turn-on
surges.
All capacitors should be placed in close proximity to the pins. A “Quiet” ground termination is desirable. This
can be achieved with a “Star” connection.
Enable
The Enable pin normally floats high. When actively, pulled low, the PMOS pass transistor shuts off, and all
internal circuits are powered down. In this state, the quiescent current is less than 1 A. This pin behaves much
like an electronic switch.
Important Notice:
All rights are reserved. Reproduction in whole or in part is prohibited without the prior written approval of GTM.
GTM reserves the right to make changes to its products without notice.
GTM semiconductor products are not warranted to be suitable for use in life-support Applications, or systems.
GTM assumes no liability for any consequence of customer product design, infringement of patents, or application assistance.
Head Office And Factory:
Taiwan: No. 17-1 Tatung Rd. Fu Kou Hsin-Chu Industrial Park, Hsin-Chu, Taiwan, R. O. C.
TEL : 886-3-597-7061 FAX : 886-3-597-9220, 597-0785
China: (201203) No.255, Jang-Jiang Tsai-Lueng RD. , Pu-Dung-Hsin District, Shang-Hai City, China
TEL : 86-21-5895-7671 ~ 4 FAX : 86-21-38950165
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