GTM GJ2148

ISSUED DATE :2004/12/28
REVISED DATE :2006/04/18B
GJ2148
1 . 5 A C M O S L o w D ro p o u t Vo l t ag e R e g u l a t o r
Description
The GJ2148 series of positive, linear regulators feature low quiescent current (45 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.
The GJ2148 is stable with an output capacitance of 4.7 F or greater.
Features
Very Low Dropout Voltage
Guaranteed 1.5A output
Over-Temperature Shutdown
Current Limiting
Short Circuit Current Fold-back
Highly Accurate± 1.5%
Low Temperature Coefficient
Functional Block Diagram
Applications
Battery Powered Widgets
Instrumentation
Wireless Devices
PC Peripherals
Portable Electronics
Package Dimensions
TO-252
REF.
A
B
C
D
E
F
S
Millimeter
Min.
Max.
6.40
6.80
5.20
5.50
6.80
7.20
2.40
3.00
2.30 REF.
0.70
0.90
0.60
0.90
REF.
G
H
J
K
L
M
R
Millimeter
Min.
Max.
0.50
0.70
2.20
2.40
0.45
0.55
0
0.15
0.90
1.50
5.40
5.80
0.80
1.20
Typical Application Circuit
GJ2148
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ISSUED DATE :2004/12/28
REVISED DATE :2006/04/18B
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
Tj
-40 ~ +125
Tj Max
150
Junction Temperature
Maximum Junction Temperature
Thermal Resistance
jc (Conductive Epoxy)*
5
/W
ja
90
/W
PD
1.2
Internal Power Dissipation
EDS Classification
W
B
*Measure jc on backside center of tab.
Electrical Characteristics VIN=VOUT(T)+2V, Ta=25
Parameter
Output Voltage
Symbol
VOUT (E)
Output Current
Current Limit
Load Regulation
IO
ILIM
REGLOAD
Dropout Voltage
VDROPOUT
unless otherwise noted
Condition
Min
IQ
IGND
Line Regulation
REGLINE
Input Voltage
Over Temperature Shutdown
Over Temperature Hysterisis
Output Voltage
Temperature Coefficient
Short Circuit Current
1.5%
V
-
A
-1.5%
VO>1.2V
1.5
VO>1.2V
1.5
2.0
-
A
VIN=VOUT(T)+2V, IO=1mA to 1.5A
-1
0.2
1
%
1.4V<VOUT(T) 2.0V
-
-
1300
2.0V<VOUT(T) 2.8V
-
-
800
2.8V<VOUT(T)
-
-
600
IO=1.5A
VO=VOUT(E)-2%
(Note2)
-
mV
VIN= VOUT(T)+2V, IO=0mA
-
45
70
A
VIN= VOUT(T)+2V, IO=1mA~1.5A
-
45
-
A
VOUT(T)<2.0V
IO=1mA
VIN=VOUT(T)+1 to 2.0V VOUT(T)<4.0V
VOUT(T)+2
4.0V VOUT(T)
-0.15
-
0.15
-0.1
0.02
0.1
-0.4
-
0.4
%
Note3
-
7
-
150
-
-
30
-
TC
-
30
-
ppm/
-
750
70
50
20
30
-
mA
PSRR
Output Voltage Noise
Unit
VIN
OTS
OTH
ISC
Power Supply Rejection
Max
IO=1mA
(Note1)
Quiescent Current
Ground Pin Current
TYP
VOUT(T)
eN
VIN=VOUT(T)+1V, VOUT<0.4V
f=100Hz
f=1kHz
f=10kHz
f=10Hz~100kHz, Io=10mA, Co=4.7 F
Io=100mA
Co=4.7 F
V
dB
Vrms
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
GJ2148-15
GJ2148-19
GJ2148-33
GJ2148-50
GJ2148
Marking
8V152
XXXX
8V192
XXXX
8V332
XXXX
8V502
XXXX
Output Voltage
1.5V
Part Number
GJ2148-18
1.9V
GJ2148-25
3.3V
GJ2148-47
Marking
8V182
XXXX
8V252
XXXX
8V472
XXXX
Output Voltage
1.8V
2.5V
4.75V
5.0V
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ISSUED DATE :2004/12/28
REVISED DATE :2006/04/18B
Detailed Description
The GJ2148 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 2.2A. During thermal shutdown, the output voltage remains low. Normal
operation is restored when the junction temperature drops below 120 .
The GJ2148 behaves like a current source when the load reaches 2.2A. However, if the load impedance drops
below 0.3 , the current drops back to 600mA to prevent excessive power dissipation. Normal operation is
restored when the load resistance exceeds 0.75 .
External Capacitors
The GJ2148 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.
Characteristics Curve
GJ2148
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ISSUED DATE :2004/12/28
REVISED DATE :2006/04/18B
115
85
55
25
-5
-45
GJ2148
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ISSUED DATE :2004/12/28
REVISED DATE :2006/04/18B
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
GJ2148
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