GTM GSC2129

ISSUED DATE :2005/06/21
REVISED DATE :2005/10/04B
GSC2129
C M O S L o w D r o p o u t Vo l t a g e R e g u l a t o r
Description
The GSC2129 series of positive, linear regulators feature low quiescent current (45 A typ.) with low dropout
voltage, making them 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.
In applications requiring a low noise, regulated supply, place a 1000pF capacitor between Bypass and Ground.
The GSC2129 is stable with an output capacitance of 4.7 F or greater.
Features
Very Low Dropout Voltage
Guaranteed 1.55A output
Over-Temperature Shutdown
Current Limiting
Highly Accurate± 1.5%
Low Temperature Coefficient
Noise Reduction Bypass Capacitor
Power-Saving Shutdown Mode
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
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ISSUED DATE :2005/06/21
REVISED DATE :2005/10/04B
Absolute Maximum Ratings
Parameter
Symbol
Ratings
Unit
Input Max Voltage
VIN
8
V
Output Current
IOUT
PD/( VIN- VO)
A
Output Voltage
VOUT
1.5~5.0
V
Operating Ambient Temperature
Topr
-40 ~ +85
Junction Temperature
Maximum Junction Temperature
Thermal Resistance
Internal Power Dissipation(
T=100 )*
Tj
-40 ~ +125
Tj Max
150
jc
20**
PD
2.5
EDS Classification
/W
W
B
*Assuming a heat sink capable of twice times ( jc)
**Estimated
Electrical Characteristics VIN=VOUT(T)+2V, VEN=VIN, TA=25
unless otherwise
Condition
Min
Typ
Max
Unit
Output Voltage
Symbol
VOUT (E)
IO=1mA
-1.5%
VOUT(T)
1.5%
V
Output Current
Current Limit
Load Regulation
IO
ILIM
REGLOAD
VOUT>1.2V
1.55
-
-
A
VOUT>1.2V
1.55
2.0
-
A
%
Parameter
(Note1)
IO=1mA to 1.5A
1.5V<VOUT(T)
Dropout Voltage
VDROPOUT
IO=1.55A
VO=VOUT(E)-2% 2.0V<VOUT(T)
-1
0.2
1
2.0V
-
-
1000
2.8V
-
-
800
-
-
600
2.8V<VOUT(T)
Quiescent Current
Ground Pin Current
IQ
IGND
(Note2)
mV
IO=0mA
-
45
70
A
IO=1mA~1.5A
-
45
-
A
VOUT(T)<2.0V
-
-
0.15
2.0V VOUT(T)
-
0.02
0.1
VIN
OTS
OTH
Note3
-
7
-
150
-
-
30
-
Output Voltage
Temperature Coefficient
TC
-
30
-
Power Supply Rejection
PSRR
Io=100mA
Co=4.7 F ceramic
Power Supply Rejection
PSRR
Io=100mA
Co=4.7 F ceramic
CBYP=0.01 F
-
50
20
15
75
55
30
-
-
30
-
Vrms
-
30
-
Vrms
2.0
-
VIN
V
VIN=2.7V to 7V
0
-
0.4
V
VEN=VIN, VIN=2.7V to 7V
-
-
0.1
A
Line Regulation
Input Voltage
Over Temperature Shutdown
Over Temperature Hysterisis
REGLINE
Output Voltage Noise
eN
Output Voltage Noise
eN
EN Input Threshold
EN Input Bias Current
Shutdown Supply Current
VEH
VEL
IEH
IEL
ISD
IO=1mA
VIN=VOUT(T)+1 to
VOUT(T)+2
f=1kHz
f=10kHz
f=100kHz
f=1kHz
F=10kHz
f=100kHz
f=10Hz~100kHz
Io=10mA,
Co=4.7 F
CBYP=0 F
f=10Hz~100kHz
Io=10mA,
Co=4.7 F
CBYP=0.01 F
VIN=2.7V to 7V
%
V
ppm/
dB
dB
VEN= 0V, VIN=2.7V to 7V
-
-
0.5
A
VIN=5.0V, VO=0, VEN<VEL
-
30
-
A
VIN=2.5V, VO=0, VEN<VEL
-
0.5
2
A
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ISSUED DATE :2005/06/21
REVISED DATE :2005/10/04B
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) =V OUT+VDROPOUT
Ordering Information ( contd. )
Part Number
GSC2129-15
GSC2129-25
GSC2129-47
Marking
9B152
XXXX
9B252
XXXX
9B472
XXXX
Output Voltage
Part Number
1.5V
GSC2129-18
2.5V
GSC2129-33
4.75V
GSC2129-50
Marking
9B182
XXXX
9B332
XXXX
9B502
XXXX
Output Voltage
1.8V
3.3V
5.0V
Characteristics Curve
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ISSUED DATE :2005/06/21
REVISED DATE :2005/10/04B
115
85
55
25
-5
-45
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ISSUED DATE :2005/06/21
REVISED DATE :2005/10/04B
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ISSUED DATE :2005/06/21
REVISED DATE :2005/10/04B
Detailed Description
The GSC2129 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 .
External Capacitors
The GSC2129 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.
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
When 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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