Global Mixed-mode Technology Inc.
G954
2A Low Dropout Regulator
Features
Fixed Output Voltage 1.2V, 1.5V, 1.8V and 2.5V
Over Current and Over Temperature Protection
Output Current 2A
TO-263 & TO-263T Package
General Description
The G954 is a high performance positive voltage
regulator designed for use in applications requiring
very low dropout voltage at up to 2 Amps. Since it has
superior dropout characteristics compared with regular
LDOs, it can be used to supply 2.5V on motherboards
or 1.5V, 1.8V on peripheral cards from the power sup-
ply thus allowing the elimination of costly heatsinks.
The G954 provides excellent regulation over variations
in line, load and temperature. It provides over current
and over temperature protection functions.
The G954 is available with 1.2V, 1.5V, 1.8V, 2.5V and
adjustable outputs in TO-263 & TO-263T package.
Applications
Battery Powered Systems
Motherboards
Peripheral Cards
Network Cards
Set Top Boxes
Notebook Computers
ORDER
NUMBER
G954-12T55U
G954-15T55U
G954-18T55U
G954-25T55U
G954-12TU5U
G954-15TU5U
G954-18TU5U
G954-25TU5U
Note: T5: TO-263
5: Bonding Code
U: Tape & Reel
MARKING
G954-12
G954-15
G954-18
G954-25
G954-12
G954-15
G954-18
G954-25
TU: TO-263T
VOLTAGE
1.2V
1.5V
1.8V
2.5V
1.2V
1.5V
1.8V
2.5V
TEMP.
RANGE
-40°C ~ +85°C
-40°C ~ +85°C
-40°C ~ +85°C
-40°C ~ +85°C
-40°C ~ +85°C
-40°C ~ +85°C
-40°C ~ +85°C
-40°C ~ +85°C
PACKAGE
(Pb free)
TO-263
TO-263
TO-263
TO-263
TO-263T
TO-263T
TO-263T
TO-263T
Pin Configuration
Typical Application Circuit
VIN
VO
Top View
1
2
3
220µF
G954
220µF
VIN GND VO
TO-263/TO-263T
Ver: 0.9
Apr 24, 2007
TEL: 886-3-5788833
http://www.gmt.com.tw
1
Global Mixed-mode Technology Inc.
(Note 1)
Input Voltage. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7V
Power Dissipation Internally Limited
(Note 2)
Maximum Junction Temperature. . . . . . . . . . . . 150°C
Storage Temperature Range. . . . -65°C
≤T
J
≤
+150°C
Reflow Temperature (soldering, 10sec) . . . . . .260°C
Thermal Resistance Junction to Ambient, (θ
JA
)
TO-263T
(1)
. . . . . . . . . . . . . . . . . . . . . . . . . . . .80°C/W
Thermal Resistance Junction to Case, (θ
Jc
)
TO-263T . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8°C/W
ESD Rating (Human Body Model) . . . . . . . . . . . . 2kV
Note
(1)
: See Recommended Minimum Footprint
G954
Absolute Maximum Ratings
(Note 1)
Input Voltage . . . . . . . . . . . . . . . . . . . . . . . 2.2V ~5.5V
Temperature Range . . . . . . . . . . . .-40°C
≤T
A
≤
+85°C
Operation Conditions
Electrical Characteristics
V
IN
= 5V, I
O
= 0.5A, C
IN
= C
OUT
= 220µF, T
A
= T
J
= 25°C unless otherwise specified (Note 3)
PARAMETER
Supply Voltage
Output Voltage
Line Regulation
SYMBOL
V
IN
V
O
CONDITION
V
IN
= V
O
+0.7V, I
O
= 10mA
V
O
+0.7V < V
IN
< 5.5V, I
O
= 10mA
G954-12 V
IN
= 2.5V, 10mA < I
OUT
< 2A
G954-15 V
IN
= 2.5V, 10mA < I
OUT
< 2A
G954-18 V
IN
= 3.8V, 10mA < I
OUT
< 2A
G954-25 V
IN
= 5V, 10mA < I
OUT
< 2A
V
IN
= 5V
fi = 120Hz, 1V
P-P
, I
O
= 100mA
G954-15
Δ
V
OUT
= 2%, I
OUT
= 2A
G954-18
Δ
V
OUT
= 2%, I
OUT
= 2A
G954-25
Δ
V
OUT
= 2%, I
OUT
= 2A
MIN
2.2
-2
---
TYP
---
V
O
0.2
MAX
5.5
2
2
UNIT
V
%
%
Load Regulation
---
1
2
%
Quiescent Current
Ripple Rejection
Dropout Voltage
Short Circuit Current
Over Temperature
I
Q
V
D
---
---
---
---
---
---
---
2.7
55
0.9
0.7
0.5
1
150
4.5
---
1.1
0.9
0.7
---
---
mA
dB
V
A
°C
Note 1:
Absolute Maximum Ratings are limits beyond which damage to the device may occur. Operating Conditions are
conditions under which the device functions but the specifications might not be guaranteed. For guaranteed specifications
and test conditions see the Electrical Characteristics.
Note2:
The maximum power dissipation is a function of the maximum junction temperature, T
Jmax
; total thermal resistance,
θ
JA
, and ambient temperature T
A
. The maximum allowable power dissipation at any ambient temperature is (T
jmax
-T
A
) /
θ
JA
. If this dissipation is exceeded, the die temperature will rise above 150°C and IC will go into thermal shutdown.
Note3:
Low duty pulse techniques are used during test to maintain junction temperature as close to ambient as possible.
Ver: 0.9
Apr 24, 2007
TEL: 886-3-5788833
http://www.gmt.com.tw
2
Global Mixed-mode Technology Inc.
Definitions
Dropout Voltage
The input/output voltage differential at which the regula-
tor output no longer maintains regulation against further
reductions in input voltage. Measured when the output
drops 2% below its nominal value, dropout voltage is
affected by junction temperature, load current and mini-
mum input supply requirements.
Line Regulation
The change in output voltage for a change in input volt-
age. The measurement is made under conditions of low
dissipation or by using pulse techniques such that aver-
age chip temperature is not significantly affected.
G954
Load Regulation
The change in output voltage for a change in load
current at constant chip temperature. The measure-
ment is made under conditions of low dissipation or by
using pulse techniques such that average chip tem-
perature is not significantly affected.
Maximum Power Dissipation
The maximum total device dissipation for which the
regulator will operate within specifications.
Quiescent Bias Current
Current which is used to operate the regulator chip
and is not delivered to the load.
Ver: 0.9
Apr 24, 2007
TEL: 886-3-5788833
http://www.gmt.com.tw
3
Global Mixed-mode Technology Inc.
Typical Performance Characteristics
V
iN
-V
OUT
=3V, C
IN
= 220µF, C
OUT
=220µF, T
A
= 25°C, unless otherwise noted.
G954
Short Circuit Current
Line Transient Response
Ripple Rejection
70
60
Ripple Rejection (dB)
G954-18 Overcurrent Protection Characteristics
50
40
30
20
10
0
10
100
1000
10000
I
L
=1A
I
L
=2A
100000
1000000
Frequency (Hz)
G954-18-Start-up
G954-18-Start-up
Ver: 0.9
Apr 24, 2007
TEL: 886-3-5788833
http://www.gmt.com.tw
4
Global Mixed-mode Technology Inc.
Typical Performance Characteristics
(continued)
Max. Power Dissipation
vs. PCB Top Copper Area
4.5
4
Max. Dissipation Power (W)
Max. Dissipation Power (W)
G954
Max. Power Dissipation vs. T
AMB
Unit : In
2
A=0.5
A=1.0
A=1.5
4.5
4
3.5
3
3.5
3
2.5
2
1.5
1
0.5
0
0.5
1.5
2.5
3.5
2
A=2.0
2.5
2
1.5
1
0.5
0
A=2.5
A=3.0
A=3.5
A=4.0
A=4.5
A=5.0
4.5
25
35
45
55
T
AMB
PCB Top Copper Area (in )
65
(°C)
75
85
G954-18 Quiescent Current vs. Temperature
3.0
1.4
I
L
=10mA
Quiescent Current (mA)
G954-18 Dropout Voltage vs. I
L
2.5
Dropout Voltage (V)
1.2
1.0
0.8
0.6
0.4
2.0
1.5
V
IN
=4V
V
IN
=5V
0.2
0.0
T
A
=-25°C
1
1.2
1.4
T
A
=25°C
T
A
=85°C
1.0
-25 -15 -5
5
15 25 35 45 55 65 75 85
Temperature (°C)
1.6
I
L
(A)
1.8
2
G954-18 Output Voltage vs. Temperature
1.825
I
L
=10mA
Output Voltage (V)
G954-18 Output Voltage vs. I
L
1.824
1.814
1.804
1.794
1.784
1.774
1.764
V
IN
=4V
V
IN
=5V
1.820
Output Voltage (V)
1.815
1.810
I
L
=4A
1.805
I
L
=5A
T
A
=25°C
1.800
5
15
25
35
45
55
Temperature (°C)
65
75
85
0
0.5
1
1.5
2
I
L
(A)
Ver: 0.9
Apr 24, 2007
TEL: 886-3-5788833
http://www.gmt.com.tw
5
