Ver: 0.2 Preliminary
Oct 01, 2004
TEL: 886-3-5788833
http://www.gmt.com.tw
1
G924
Global Mixed-mode Technology Inc.
300mA Low-Noise LDO Regulators
Features
Low, 90A No-Load Supply Current
Guaranteed 300mA Output Current
Dropout Voltage is 200mV @ 150mA Load
PSRR=53dB @ 1kHz
Over-Temperature Protection and Short-Circuit
Protection
Max. Supply Current in Shutdown Mode < 1A
Low Output Noise at 28V
RMS
Stable with low cost ceramic capacitors
Output voltage: 1.20V~5.00V
Applications
Notebook Computers
Cellular Phones
PDAs
Digital still Camera and Video Recorders
Hand-Held Devices
Audio Codec
General Description
The G924 is a low supply current, low dropout linear
regulator that comes in a space saving SOT-23-5
package. The supply current at no-load is 90A. In the
shutdown mode, the maximum supply current is less
than 1A. Operating voltage range of the G924 is from
2.5V to 5.5V. The over-current protection limit is set at
550mA typical and 400mA minimum. An over-tem-
perature protection circuit is built-in in the G924 to
prevent thermal overload. These power saving
features make the G924 ideal for use in the battery-
powered applications such as notebook computers,
cellular phones, and PDA's.
Pin Configuration
Typical Application Circuit
OUT
BYP
SOT-23-5
G924
5
4
1
2
3
GND
SHDN
VIN
OUT
GND
SHDN
G924
C
IN
1F
_
BATTERY
OUTPUT
VOLTAGE
C
OUT
1
F
Fixed mode
BYP
C
BYP
10nF
VIN
OUT
BYP
SOT-23-5
G924
5
4
1
2
3
GND
SHDN
VIN
OUT
GND
SHDN
G924
C
IN
1F
_
BATTERY
OUTPUT
VOLTAGE
C
OUT
1
F
Fixed mode
BYP
C
BYP
10nF
VIN
Ver: 0.2 Preliminary
Oct 01, 2004
TEL: 886-3-5788833
http://www.gmt.com.tw
2
G924
Global Mixed-mode Technology Inc.
Ordering Information
For other output voltage, please contact us at sales
@
gmt.com.tw
Note:
T1: SOT-23-5
U: Tape & Reel
Selector Guide
ORDER NUMBER
ORDER NUMBER
(Pb free)
OUTPUT VOLTAGE (V)
MARKING
G924-120T1U G924-120T1Uf
1.20
94AAx
G924-130T1U G924-130T1Uf
1.30
94ABx
G924-140T1U G924-140T1Uf
1.40
94ACx
G924-150T1U G924-150T1Uf
1.50
94ADx
G924-160T1U G924-160T1Uf
1.60
94AEx
G924-170T1U G924-170T1Uf
1.70
94AFx
G924-180T1U G924-180T1Uf
1.80
94AGx
G924-190T1U G924-190T1Uf
1.90
94AHx
G924-200T1U G924-200T1Uf
2.00
94AIx
G924-210T1U G924-210T1Uf
2.10
94AJx
G924-220T1U G924-220T1Uf
2.20
94AKx
G924-230T1U G924-230T1Uf
2.30
94ALx
G924-240T1U G924-240T1Uf
2.40
94AMx
G924-250T1U G924-250T1Uf
2.50
94ANx
G924-260T1U G924-260T1Uf
2.60
94AOx
G924-270T1U G924-270T1Uf
2.70
94APx
G924-280T1U G924-280T1Uf
2.80
94AQx
G924-285T1U G924-285T1Uf
2.85
94ARx
G924-290T1U G924-290T1Uf
2.90
94ASx
G924-300T1U G924-300T1Uf
3.00
94ATx
G924-310T1U G924-310T1Uf
3.10
94AUx
G924-315T1U G924-315T1Uf
3.15
94AVx
G924-320T1U G924-320T1Uf
3.20
94AWx
G924-330T1U G924-330T1Uf
3.30
94AXx
G924-340T1U G924-340T1Uf
3.40
94AYx
G924-350T1U G924-350T1Uf
3.50
94AZx
G924-360T1U G924-360T1Uf
3.60
94BAx
G924-370T1U G924-370T1Uf
3.70
94BBx
G924-380T1U G924-380T1Uf
3.80
94BCx
G924-390T1U G924-390T1Uf
3.90
94BDx
G924-400T1U G924-400T1Uf
4.00
94BEx
G924-410T1U G924-410T1Uf
4.10
94BFx
G924-420T1U G924-420T1Uf
4.20
94BGx
G924-430T1U G924-430T1Uf
4.30
94BHx
G924-440T1U G924-440T1Uf
4.40
94BIx
G924-450T1U G924-450T1Uf
4.50
94BJx
G924-460T1U G924-460T1Uf
4.60
94BKx
G924-470T1U G924-470T1Uf
4.70
94BLx
G924-475T1U G924-475T1Uf
4.75
94BMx
G924-480T1U G924-480T1Uf
4.80
94BNx
G924-490T1U G924-490T1Uf
4.90
94BOx
G924-500T1U G924-500T1Uf
5.00
94BPx
ORDER
NUMBER
ORDER NUMBER
(Pb free)
MARKING VOLTAGE
TEMP.
RANGE
PACKAGE
G924-330T1U G924-330T1Uf
94AXx
3.30V -40C~
+85C SOT-23-5
Ver: 0.2 Preliminary
Oct 01, 2004
TEL: 886-3-5788833
http://www.gmt.com.tw
3
G924
Global Mixed-mode Technology Inc.
Absolute Maximum Ratings
V
IN
to GND.....................................-0.3V to +6.5V
Output Short-Circuit Duration........................Infinite
SHDN to GND.............................-0.3V to V
IN
+0.3V
OUT to GND...........................-0.3V to (V
IN
+ 0.3V)
Continuous Power Dissipation (T
A
= +25C)
SOT-23-5................................................520mW
Operating Temperature Range...........-40C to +85C
Junction Temperature..............................+150C
JA
(1)
.............................................240C/Watt
Storage Temperature Range..........-65C to +150C
Reflow Temperature (soldering, 10sec)............260C
Note (1): See Recommended Minimum Footprint
Stresses beyond those listed under "Absolute Maximum Ratings" may cause permanent damage to the device. These are stress ratings
only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the
specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.
Electrical Characteristics
(V
IN
=5V, V
SHDN
=V
IN
, T
A
=T
J
=25C, unless otherwise noted.) (Note 1)
PARAMETER SYMBOL
CONDITION MIN
TYP
MAX UNIT
Input Voltage (Note 2)
V
IN
2.5
---
5.5
V
V
OUT
2.50V, I
OUT
=1mA
-2 --- 2
2.50V>V
OUT
1.80V, I
OUT
=1mA
-3 --- 3
Output Voltage Accuracy
V
OUT
1.80V>V
OUT
1.20V, I
OUT
=1mA
-4 --- 4
%
Maximum Output Current
300
---
---
mA
Current Limit (Note 3)
I
LIM
400
550
---
mA
Short Circuit Current
Isc
---
280
---
mA
Ground Pin Current
I
Q
--- 90 ---
A
V
OUT
=1.50V ---
1.36
---
V
OUT
=1.80V ---
1.10
---
V
OUT
=2.50V ---
0.58
---
V
OUT
=3.00V ---
0.41
---
V
OUT
=3.30V ---
0.36
---
V
OUT
=4.75V ---
0.25
---
Dropout Voltage (Note 4)
V
DROP
I
OUT
=300mA
V
OUT
=5.00V ---
0.24
---
V
Line Regulation
V
LNR
V
IN
=V
OUT
+0.1V,to 5.5V I
OUT
=10mA ---
0.06
---
%/V
Load Regulation
V
LDR
I
OUT
= 10mA to 300mA
---
0.02 ---
%/mA
Ripple Rejection
PSRR F=1kHz, 0.45V
P-P
, I
OUT
=10mA ---
53
---
dB
Output Voltage Noise
(10Hz to 100kHz)
e
n
C
OUT
= 1F, I
OUT
= 1mA, C
BYP
= 10nF
--- 28 ---
V
RMS
SHUTDOWN
V
IH
Regulator
enabled
1.5 --- ---
SHDN
Input Threshold
V
IL
Regulator
shutdown
--- --- 0.4
V
SHDN
Input Bias Current
I
SHDN
V
SHDN
= V
IN
T
A
= +25C
--- 0.003 1 A
Shutdown Supply Current
I
QSHDN
V
OUT
= 0V
T
A
= +25C
---
0.2
1
A
THERMAL PROTECTION
Thermal Shutdown Temperature
T
SHDN
--- 145 ---
C
Thermal Shutdown Hysteresis
T
SHDN
---
25
---
C
Note 1: Limits is 100% production tested at T
A
= +25C. Low duty pulse techniques are used during test to
maintain junction temperature as close to ambient as possible.
Note 2: Guaranteed by line regulation test.
Note 3: Not tested. For design purposes, the current limit should be considered 400mA minimum.
Note 4: The dropout voltage is defined as (V
IN
-V
OUT
) when V
OUT
is 100mV below the target value of V
OUT
. The per-
formance of every G924 part, see "Typical Performance Characteristics".
Ver: 0.2 Preliminary
Oct 01, 2004
TEL: 886-3-5788833
http://www.gmt.com.tw
4
G924
Global Mixed-mode Technology Inc.
Typical Performance Characteristics
(V
IN
=5V, C
IN
=1F, C
OUT
=1F, V
SHDN
= V
IN
, G924-475, T
A
=25C, unless otherwise noted.)
Short Circuit Current
Turn-ON
Turn-OFF
Line Transient
Load Transient
0
10
20
30
40
50
60
70
0.01
0.1
1
10
100
Frequency (KHz)
PSR
R (
d
B)
100mA
300mA
200mA
V
IN
=6V ;
C
IN
=1F ; C
OUT
=1F
C
BYP
=10nF ; V
r
=224mv
Ripple Rejection
Ver: 0.2 Preliminary
Oct 01, 2004
TEL: 886-3-5788833
http://www.gmt.com.tw
5
G924
Global Mixed-mode Technology Inc.
Typical Performance Characteristics
(continued)
0
50
100
150
200
250
300
0
50
100
150
200
250
300
I
L
(mA)
D
r
opout
V
o
lt
age (
m
V
)
T
A
=85C
4.2
4.3
4.4
4.5
4.6
4.7
4.8
4.9
5.0
5.1
5.2
-25 -15 -5
5 15 25 35 45 55 65 75 85
Temperature (C)
O
u
tput Voltage (V)
V
IN
=5.0V
V
IN
=5.5V
I
L
=10mA
Overcurrent Protection Characteristics
Dropout Voltage vs. I
L
T
A
=25C
T
A
=-25C
Output Voltage vs. Temperature
Output Noise
0
50
100
150
200
250
300
350
400
0.1
0.4
0.7
1.0
1.3
1.6
1.9
2.2
Input-Output Voltage Differential V
IN
-V
OUT
(V)
Out
put
Cur
r
ent
(m
A
)
1oz Copper on SOT-23-5 Package
Mounted on recommended mimimum
footprint (R
JA
=240C/W)
Note: V
IN
(max) <= 5.5V
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
25 35 45 55 65 75 85 95 105 115 125
Amibent Temperature T
A
(C)
P
o
wer Di
s
s
i
pat
i
on (W)
Still Air
1oz Copper on SOT-23-5 Package
Mounted on recommended mimimum
footprint (R
JA
=240C/W)
Still air
T
A
=85C
Maximum Recommended Output Current
Safe Operating Area
[Power Dissipation Limit]
T
A
=55C
T
A
=25C
Max. Power Dissipation vs. Temperature
Ver: 0.2 Preliminary
Oct 01, 2004
TEL: 886-3-5788833
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6
G924
Global Mixed-mode Technology Inc.
Pin Description
PIN
NAME
FUNCTION
1
SHDN
Active-High Enable Input. A logic low reduces the supply current to less than 1A. Connect to IN for
normal operation.
2 GND
Ground. This pin also functions as a heat sink. Solder to large pads or the circuit board ground
plane to maximize thermal dissipation.
3 BYP
This is a reference bypass pin. It should connect external 10nF capacitor to GND to reduce output
noise. Bypass capacitor must be no less than 1nF. (C
BYP
1nF)
4
OUT
Regulator Output. Sources up to 300mA. Bypass with a 1F capacitor to GND.
5
VIN
Regulator Input. Supply voltage can range from +2.5V to +5.5V. Bypass with 1F to GND.
Detailed Description
The block diagram of the G924 is shown in Figure 1. It
consists of an error amplifier, 1.20V bandgap refer-
ence, PMOS output transistor, internal feedback
voltage divider, shutdown logic, over current protection
circuit, and over temperature protection circuit.
The internal feedback voltage divider's central tap is
connected to the non-inverting input of the error ampli-
fier. The error amplifier compares non-inverting input
with the 1.20V bandgap reference. If the feedback
voltage is higher than 1.20V, the error amplifier's out-
put becomes higher so that the PMOS output transis-
tor has a smaller gate-to-source voltage (V
GS
). This
reduces the current carrying capability of the PMOS
output transistor, as a result the output voltage de-
creases until the feedback voltage is equal to 1.20V.
Similarly, when the feedback voltage is less than
1.20V, the error amplifier causes the output PMOS to
conduct more current to pull the feedback voltage up
to 1.20V. Thus, through this feedback action, the error
amplifier, output PMOS, and the voltage dividers effec-
tively form a unity-gain amplifier with the feedback
voltage force to be the same as the 1.20V bandgap
reference. The output voltage, V
OUT
, is then given by
the following equation:
V
OUT
= 1.20 (1 + R1/R2).
(1)
Alternatively, the relationship between R1 and R2 is
given by:
R1 = R2 (V
OUT
/ 1.20 - 1).
(2)
For the output voltage versions of G924, the output
voltages are 1.20V for G924-120, 2.50V for G924-250,
3.30V for G924-330, etc.
Figure 1. Functional Diagram
SHDN
VIN
OUT
SHUTDOWN
LOGIC
1.2V
Vref
ERROR
AMP
OVER CURRENT
PROTECT & DYNAMIC
FEEDBACK
GND
R1
R2
OVER TEMP.
PROTECT
BYP
C
BYP
SHDN
VIN
OUT
SHUTDOWN
LOGIC
1.2V
Vref
ERROR
AMP
OVER CURRENT
PROTECT & DYNAMIC
FEEDBACK
GND
R1
R2
OVER TEMP.
PROTECT
BYP
C
BYP
Ver: 0.2 Preliminary
Oct 01, 2004
TEL: 886-3-5788833
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7
G924
Global Mixed-mode Technology Inc.
Over Current Protection
The G924 uses a current mirror to monitor the output
current. A small portion of the PMOS output transis-
tor's current is mirrored onto a resistor such that the
voltage across this resistor is proportional to the output
current. This voltage is compared against the 1.20V
reference. Once the output current exceeds the limit,
the PMOS output transistor is turned off. Once the
output transistor is turned off, the current monitoring
voltage decreases to zero, and the output PMOS is
turned on again. If the over current condition persist,
the over current protection circuit will be triggered
again. Thus, when the output is shorted to ground, the
output current will be alternating between 0 and the
over current limit. The typical over current limit of the
G924 is set to 550mA. Note that the input bypass ca-
pacitor of 1F must be used in this case to filter out
the input voltage spike caused by the surge current
due to the inductive effect of the package pin and the
printed circuit board's routing wire. Otherwise, the ac-
tual voltage at the IN pin may exceed the absolute
maximum rating.
Over Temperature Protection
To prevent abnormal temperature from occurring, the
G924 has a built-in temperature monitoring circuit.
When it detects the temperature is above 145
o
C, the
output transistor is turned off. When the IC is cooled
down to below 120
o
C, the output is turned on again. In
this way, the G924 will be protected against abnormal
junction temperature during operation.
Shutdown Mode
When the SHDN pin is connected a logic low voltage,
the G924 enters shutdown mode. All the analog cir-
cuits are turned off completely, which reduces the
current consumption to only the leakage current. The
output is disconnected from the input. When the output
has no load at all, the output voltage will be dis-
charged to ground through the internal resistor voltage
divider.
Operating Region and Power Dissipation
Since the G924 is a linear regulator, its power dissipa-
tion is always given by P = I
OUT
(V
IN
V
OUT
). The
maximum power dissipation is given by:
P
DMAX
= (T
J
T
A
)/
JA
= (150-25) / 240 = 520mW
Where (T
J
T
A
) is the temperature difference the
G924 die and the ambient air,
JA
, is the thermal re-
sistance of the chosen package to the ambient air. For
surface mount device, heat sinking is accomplished by
using the heat spreading capabilities of the PC board
and its copper traces. In the case of a SOT-23-5
package, the thermal resistance is typically
240
o
C/Watt. (See Recommended Minimum Footprint).
Refer to "Safe Operating Area" of the Typical Per-
formance Characteristics is the G924 valid operating
region & refer to "Maximum Power Dissipation vs.
Temperature" is the maximum power dissipation of
SOT-23-5.
The die attachment area of the G924's lead frame is
connected to pin 2, which is the GND pin. Therefore,
the GND pin of G924 can carry away the heat of the
G924 die very effectively. To improve the power dis-
sipation, connect the GND pin to ground using a large
ground plane near the GND pin.
Applications Information
Capacitor Selection and Regulator Stability
Normally, use a 1F capacitor on the input and a 1F
capacitor on the output of the G924. Larger input ca-
pacitor values and lower ESR provide better sup-
ply-noise rejection and transient response. A higher-
value input capacitor (10F) may be necessary if large,
fast transients are anticipated and the device is lo-
cated several inches from the power source.
Power-Supply Rejection and Operation from
Sources Other than Batteries
The G924 is designed to deliver low dropout voltages
and low quiescent currents in battery powered sys-
tems. Power-supply rejection is 53dB at low frequen-
cies as the frequency increases above 20kHz; the
output capacitor is the major contributor to the rejec-
tion of power-supply noise.
When operating from sources other than batteries,
improve supply-noise rejection and transient response
by increasing the values of the input and output ca-
pacitors, and using passive filtering techniques.
Load Transient Considerations
The G924 load-transient response graphs show two
components of the output response: a DC shift of the
output voltage due to the different load currents, and
the transient response. Typical overshoot for step
changes in the load current from 10mA to 300mA is
30mV. Increasing the output capacitor's value and
decreasing its ESR attenuates transient spikes.
Input-Output (Dropout) Voltage
A regulator's minimum input-output voltage differential
(or dropout voltage) determines the lowest usable
supply voltage. In battery-powered systems, this will
determine the useful end-of-life battery voltage. Be-
cause the G924 use a P-channel MOSFET pass tran-
sistor, their dropout voltage is a function of R
DS(ON)
multiplied by the load current cause the G924 use a
P-channel MOSFET pass transistor, their dropout
voltage is a function of R
DS(ON)
multiplied by the load
current.
Ver: 0.2 Preliminary
Oct 01, 2004
TEL: 886-3-5788833
http://www.gmt.com.tw
8
G924
Global Mixed-mode Technology Inc.
Layout Guide
An input capacitance of 1F is required between the
G924 input pin and ground (the amount of the capaci-
tance may be increased without limit), This capacitor
must be located a distance of not more than 1cm from
the input and return to a clean analog ground.
Input capacitor can filter out the input voltage spike
caused by the surge current due to the inductive effect
of the package pin and the printed circuit board's rout-
ing wire. Otherwise, the actual voltage at the IN pin
may exceed the absolute maximum rating.
The output capacitor also must be located a distance
of not more than 1cm from output to a clean analog
ground. Because it can filter out the output spike
caused by the surge current due to the inductive effect
of the package pin and the printed circuit board's rout-
ing wire.
Recommend Minimum Footprint
SOT-23-5
Ver: 0.2 Preliminary
Oct 01, 2004
TEL: 886-3-5788833
http://www.gmt.com.tw
9
G924
Global Mixed-mode Technology Inc.
Package Information
Note:
1. Package body sizes exclude mold flash protrusions or gate burrs
2. Tolerance 0.1000 mm (4mil) unless otherwise specified
3. Coplanarity: 0.1000mm
4. Dimension L is measured in gage plane
DIMENSIONS IN MILLIMETERS
SYMBOLS
MIN
NOM MAX
A 1.00 1.10 1.30
A1 0.00 ----- 0.10
A2 0.70 0.80 0.90
b 0.35 0.40
0.50
C 0.10 0.15 0.25
D 2.70 2.90 3.10
E 1.40 1.60 1.80
e -----
1.90(TYP)
-----
e1 ----- 0.95 -----
H 2.60 2.80 3.00
L 0.37 ------ -----
1
1 5 9
Taping Specification
PACKAGE Q'TY/REEL
SOT-23-5 3,000
ea
GMT Inc. does not assume any responsibility for use of any circuitry described, no circuit patent licenses are implied and GMT Inc. reserves the right at any time without notice to change said circuitry and specifications.
E
e
D
H
1
L
C
b
A2
A1
A
e1
E
e
D
H
1
L
C
b
A2
A1
A
e1
Feed Direction
SOT-23-5 Package Orientation
Feed Direction
SOT-23-5 Package Orientation
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