GTM GQ2131

ISSUED DATE :2005/07/05
REVISED DATE :
GQ2131
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 GQ2131 is a fixed 1.2V of positive, linear regulators feature low quiescent current (60 A typ.) with low
dropout voltage, making them ideal for battery applications.
This rugged device has both Thermal Shutdown, and Current Fold-back to prevent device failure under the
“Worst” of operating conditions.
An additional feature is a “Power Good” detector, which pulls low when the output is out of regulation.
The GQ2131 is stable with an output capacitance of 2.2 F or greater.
Features
Very Low Dropout Voltage
Guaranteed 150mA output
Over-Temperature Shutdown
Current Limiting
Short Circuit Current Fold-back
Accurate± 3.0%
Power Good Output Function
Power-saving Shutdown Mode
Low Temperature coefficient
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 :2005/07/05
REVISED DATE :
Fig 1. Typical Application Schematic
Fig 2. Typical Application For Processor
VID Code Power Sequencing Schematic
Pin Description
Pin Number
1
2
Pin Name
VIN
Gnd
3
EN
4
5
PG
VOUT
Pin Function
Supply Input
Ground
Enable/Shutdown (Input): CMOS compatible input.
Logic high= enable; Logic low= shutdown. Do not leave open.
Power Good Output
Regulator Output
Ordering Information ( contd. )
Part Number
GQ2131-12
Marking
1C122
XXXX
Output Voltage
Part Number
Marking
Output Voltage
1.2V
Detailed Description
The GQ2131 of COMS regulator contains a PMOS pass transistor, voltage reference, error amplifier, over
-current protection, thermal shutdown and Power Good function.
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 GQ2131 switches from voltage mode to current mode when the load exceeds the rated output current.
This prevents over-stress. The GQ2131 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 GQ2131 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.
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.
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ISSUED DATE :2005/07/05
REVISED DATE :
Power Good
The GQ2131 includes the Power Good feature. When the output is not within 15% of the specified voltage, it
pulls low. This can occur under the following conditions:
1) Input Voltage too low.
2) During Over-Temperature.
3) During Over-Current.
4) If output is pulled up.
(Note: PG pin is an open-drain output.)
Absolute Maximum Ratings
Parameter
Symbol
Ratings
Unit
Input Max Voltage
VIN
7
V
Output Current
IOUT
PD/( VIN- VO)
mA
GND-0.3 to VIN+0.3
V
Input, Output Voltage
Operating Ambient Temperature
Junction Temperature
Maximum Junction Temperature
Thermal Resistance
Power Dissipation( T=100 )
Topr
-40 ~ +85
Tj
-40 ~ +125
Tj Max
150
ja
260
/W
PD
380
mW
EDS Classification
B
Electrical Characteristics Ta=25
Parameter
Output Voltage
Current Limit
Load Regulation
Dropout Voltage
Quiescent Current
Ground Pin Current
Line Regulation
Input Voltage
Over Temperature Shutdown
Over Temperature Hysterisis
Symbol
VO
ILIM
REGLOAD
VDROPOUT
IQ
IGND
REGLINE
VIN
OTS
OTH
Output Voltage
Temperature Coefficient
TC
Power Supply Rejection
PSRR
Output Voltage Noise
EN Input Threshold
EN Input Bias Current
Shutdown Supply Current
Shutdown Output Voltage
Output Under Voltage
PG Leakage Current
PG Voltage Low
VPG Delay
eN
VEH
VEL
IEH
IEL
ISD
VO,SD
VUV
ILC
VOL
TPGD
VIN=2.7V, VEN= VIN,
O=100uA
unless otherwise noted
Condition
Min
TYP
Max
Unit
IO=0.1mA
-3.0%
-
3.0%
V
VO<0.1V
IO=0.1mA to 150mA
IO=150mA, VOUT=VO-2%
150
-4
-
350
1
-
4
1300
mA
%
mV
VIN=6V, IO=0mA, VO=VO(NOM)
VIN=6V, IO=1mA to150mA
IO=0.1mA, VIN=2.7V to 6V
-0.3
60
65
-
80
0.3
A
A
%
2.7
-
6
V
-
150
-
-
30
-
-
30
-
Io=100mA
Co=2.2 F
f=10Hz to 100kHz
Io=10mA
ppm/
f=1kHz
-
50
-
f=10kHz
-
20
-
f=100kHz
-
15
-
Co=2.2 F
-
30
-
Vrms
1.6
0
0
1.5
0.1
0.1
0.5
0.1
-
VIN
0.4
1
0.4
95
0.1
5
V
V
A
A
A
V
%Vo(NOM)
A
V
ms
VEN=VIN
VEN= 0V
VIN=5V, VO=0V, VEN=0V
Output Loading 1200 , VEN=0V
PG ON @ % of VOUT
VPG=6V, PG is off
ISINK=0.1mA
See Timing Diagram on page 5
dB
Note 1: VIN (MIN) =VOUT+VDROPOUT
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ISSUED DATE :2005/07/05
REVISED DATE :
Characteristics Curve
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ISSUED DATE :2005/07/05
REVISED DATE :
Timing Diagram
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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