GTM GSC2127

ISSUED DATE :2006/02/24
REVISED DATE :
GSC2127
7 5 0 m A 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 GSC2127 series of positive, linear regulators feature low quiescent current (45 A typ.) with low dropout
voltage, making then ideal for battery applications.
Output voltages are set at the factory and trimmed to 1.5% accuracy.
These rugged devices have 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 GSC2127 is stable with an output capacitance of 4.7 F or greater.
Features
Very Low Dropout Voltage
Guaranteed 750mA output
Over-Temperature Shutdown
Current Limiting
Short Circuit Current Fold-back
Low Temperature Coefficient
Noise Reduction Bypass Capacitor
Power-saving Shutdown Mode
Power Good Output Function
Functional Block Diagram
Applications
Battery Powered Widgets
Instrumentation
Wireless Devices
PC Peripherals
Portable Electronics
Package Dimensions
REF.
A
B
C
D
E
F
Millimeter
Min.
Max.
5.80
4.80
3.80
0°
0.40
0.19
6.20
5.00
4.00
8°
0.90
0.25
REF.
M
H
L
J
K
G
Millimeter
Min.
Max.
0.10
0.25
0.35
0.49
1.35
1.75
0.375 REF.
45°
1.27 TYP.
Typical Application Circuit
GSC2127
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ISSUED DATE :2006/02/24
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
1.5~3.3
V
Operating Ambient Temperature
Topr
-40 ~ +85
Junction Temperature
Maximum Junction Temperature
Internal Power Dissipation( T=100 )
Tj
-40 ~ +125
Tj Max
150
PD
810
EDS Classification
mW
B
Electrical Characteristics TA=25
unless otherwise noted
(VIN=VOUT (T) +2V, VEN=VIN, CIN=1 F, COUT=4.7 F)
Parameter
Output Voltage
Output Current
Current Limit
Short Circuit Current
Load Regulation
Dropout Voltage
Symbol
VOUT (E)
(Note1)
Condition
Min
TYP
Max
Unit
IO=1mA, VIN=VOUT(T)+2V
-1.5
VOUT(T)
1.5
%
VO>1.2V
750
-
-
mA
IO
ILIM
ISC
VO>1.2V
750
-
-
mA
VIN=VOUT(T)+1V, VO < 0.4V
-
750
-
mA
REGLOAD
VIN=VOUT(T)+2V, IO=1mA to 750mA
%
VDROPOUT
IO=750mA
VO=VOUT(E)-2%
-1
0.2
1
VOUT(T)=1.5V
-
-
1000
VOUT(T)=1.8V
-
-
650
VOUT(T) 2.0V
Quiescent Current
Ground Pin Current
IQ
VIN=VOUT(T)+2V, IO=0mA
IGND
VIN=VOUT(T)+2V, IO=1mA to 750mA
VOUT(T)<2.0V
Line Regulation
Input Voltage
Over Temperature Shutdown
Over Temperature Hysterisis
Output Voltage
Temperature Coefficient
Power Supply Rejection
Output Voltage Noise
EN Input Threshold
EN Input Bias Current
Shutdown Supply Current
Output Under Voltage
Output Over Voltage
PG Leakage Current
PG Voltage Low
(Note2)
REGLINE
IO=1mA
VIN=VOUT(T)+1 to 2.0V VOUT(T)<4.0V
VOUT(T)+2
4.0V VOUT(T)
-
-
500
-
45
70
A
A
-
45
-
-0.15
-
0.15
-0.1
0.02
0.1
-0.4
-
0.4
VIN
OTS
OTH
Note3
-
7
-
150
-
-
30
-
TC
-
30
-
f=1kHz
-
75
-
f=10kHz
-
55
-
f=100kHz
PSRR
eN
VEH
VEL
IEH
IEL
ISD
VUV
VOV
ILC
VOL
Io=100mA
Co=4.7 F
(ceramic)
mV
%
V
ppm/
dB
-
30
-
f=10Hz~100kHz, Io=10mA, Co=4.7 F
-
30
-
Vrms
VIN=2.7V to 7V
2.0
-
VIN
V
VIN=2.7V to 7V
0
-
0.4
V
VEN=VIN, VIN=2.7V to 7V
-
-
1
A
VEN= 0V, VIN=2.7V to 7V
-
-
1
A
VIN=5V, VO=0V, VEN<VEL
-
0.5
2
PG goes Low when VOUT too Low
-
-
84
% VOUT(T)
PG goes Low when VOUT too High
105
-
-
% VOUT(T)
A
VPG=7V
-
-
1.0
A
ISINK=0.25mA
-
-
0.4
V
Note 1: V OUT (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
GSC2127
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ISSUED DATE :2006/02/24
REVISED DATE :
Ordering Information ( contd. )
Part Number
GSC2127-15
GSC2127-25
Marking
7B152
XXXX
7B252
XXXX
Output Voltage
Part Number
1.5V
GSC2127-18
2.5V
GSC2127-33
Marking
7B182
XXXX
7B332
XXXX
Output Voltage
1.8V
3.3V
Detailed Description
The GSC2127 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
140 , or the current exceeds 2.2A. During thermal shutdown, the output voltage remains low. Normal
operation is restored when the junction temperature drops below 120 .
The GSC2127 behaves like a current source when the load reaches 2.2A. However, if the load impedance
drops below 0.3ohms, the current drops back to 600mA to prevent excessive power dissipation. Normal
operation is restored when the load resistance exceeds 0.75ohms.
External Capacitors
The GSC2127 is stable with an output capacitance to ground of 4.7 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
When EN pin is pulled low, the PMOS pass transistor shuts off, and all internal circuits are powered down. In
this state, the quiescent current is less than 2 A. This pin behaves much like an electronic switch.
100K resistor is necessary between VEN source and EN pin when VEN is high than VIN.
(Note: There is no internal pull-up for EN pin. It can not be floating.)
Power Good
The GSC2127 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.)
GSC2127
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ISSUED DATE :2006/02/24
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Characteristics Curve
GSC2127
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ISSUED DATE :2006/02/24
REVISED DATE :
GSC2127
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ISSUED DATE :2006/02/24
REVISED DATE :
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
GSC2127
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