GMT G914 150ma low-dropout linear regulator Datasheet

G914
Global Mixed-mode Technology Inc.
150mA Low-Dropout Linear Regulators
Features
General Description
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The G914 is a low supply current, low dropout linear
regulator that comes in a space saving SOT23-5 package. The supply current at no-load is 52µA. In the
shutdown mode, the maximum supply current is less
than 1µA. Operating voltage range of the G914 is from
2.5V to 5.5V. The over-current protection limit is set at
370mA typical and 150mA minimum. An overtemperature protection circuit is built-in in the G914 to
prevent thermal overload. These power saving features make the G914 ideal for use in the battery-powered applications such as notebook computers, cellular phones, and PDA’s.
Low, 52µA Ground Current
Guaranteed 150mA Output Current
Dropout Voltage is 100mV @ 50mA Load
Over-Temperature Protection and Short-Circuit
Protection
„ Adjustable Mode: from 2.5V to 5.5V
„ Max. Supply Current in Shutdown Mode < 1µA
„ Low Output Noise is 170 µVRMS
Applications
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Notebook Computers
Cellular Phones
PDAs
Digital still Camera and Video Recorders
Hand-Held Devices
Bar Code Scanners
The G914 is a adjustable output version in a small
SOT 23-5 package.
Ordering Information
TEMP.
RANGE
PINPACKAGE
-40°C~ +85°C
SOT 23-5
PART MARKING VOLTAGE
G914
14
Adjustable
Pin Configuration
IN
1
5
OUTPUT
VOLTAGE
OUT
IN
OUT
R1
+
G914
ADJ
GND
2
-
G914
BATTERY
C IN
1µF
SHDN
GND
COUT
1µF
R2
470pF
SHDN
3
4
ADJ
Adjustable mode
SOT23-5
VOUT =1.250 X ( R2/R1+1)
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Ver 0.1 Preliminary
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G914
Global Mixed-mode Technology Inc.
Continuous Power Dissipation (TA = +25°C)
SOT23-5……………………………………...…..568 mW
Operating Temperature Range………...-40°C to +85°C
Junction Temperature……………………….……+150°C
θJA….…..……………….…………….…..…..220°C/Watt
Storage Temperature Range………….-65°C to +160°C
Lead Temperature (soldering, 10sec)..…………+300°C
Absolute Maximum Ratings
VIN to GND……………………………………-0.3V to +7V
Output Short-Circuit Duration………………….….Infinite
SET to GND.……………………………..…..-0.3V to +7V
SHDN to GND…………………..………….-0.3V to +7V
SHDN to IN….…………………..…………..-7V to +0.3V
OUT to GND…………………………-0.3V to (VIN + 0.3V)
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
(VIN = VOUT +1V; V SHDN = VIN; CIN = COUT = 1µF = TA = TJ = +25°C, unless otherwise noted.) (Note 1)
PARAMETER
SYMBOL CONDITIONS
MIN TYP MAX UNITS
Input Voltage (Note 2)
Output Voltage Accuracy
Adjustable Output Voltage Range (Note 3)
Maximum Output Current
Current Limit
VIN
VOUT
VOUT
Dropout Voltage (Note 3)
VDROP
Line Regulation
∆VLNR
VOUT = 0V
ILOAD = 0mA
ILOAD = 150mA
IOUT = 1mA
IOUT = 50mA
IOUT =150mA
VIN=VO +0.1V to 5.5V, IOUT = 1mA
Load Regulation
∆VLDR
IOUT = 0mA to 150mA
Ground Pin Current
Output Voltage Temperature Coefficient
Output Voltage Noise (10HZ to 100KHZ)
ILIM
Variation from specified VOUT, IOUT=1mA
IQ
Note2
-2
2.5
150
52
%/V
mV
40
ppm/°C
CADJ = 10nF
170
TA = +25°C
µA
30
192
VIH
VIL
80
2
100
340
0.1
CADJ = 470pF
IL = 150mA
V
%
V
mA
mA
370
∆VO / ∆T IOUT = 40mA, TJ = 25°C to 125°C
en
5.5
2
5.5
mV
µVRMS
SHUTDOWN
SHDN Input Bias Current
I SHDN
Regulator enabled
Regulator shutdown
V SHDN = VIN
0.007
0.1
µA
Shutdown Supply Current
ADJ INPUT
ADJ Input Leakage Current
THERMAL PROTECTION
Thermal Shutdown Temperature
Thermal Shutdown Hysteresis
IQSHDN
VOUT = 0V
TA = +25°C
0.06
1
µA
VADJ = 1.3V
TA = +25°C
5
20
nA
SHDN Input Threshold
IADJ
TSHDN
∆TSHDN
2
0.4
150
15
V
°C
°C
Note 1: Limits is 100% production tested at TA= +25°C. Low duty pulse techniques are used during test to
maintain junction temperature as close to ambient as possible.
Note 2: VIN (min) = VOUT +VDROP.
Note 3: The dropout voltage is defined as (VIN-VOUT) when VOUT is 100mV below the value of VOUT for VIN = VOUT +2V.
TEL: 886-3-5788833
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Ver 0.1 Preliminary
Nov 05, 2001
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Global Mixed-mode Technology Inc.
G914
Pin Description
PIN
NAME
FUNCTION
1
IN
2
GND
3
SHDN
4
ADJ
5
OUT
Regulator Input. Supply voltage can range from +2.5V to +5.5V. Bypass with 1µF to GND
Ground. This pin also functions as a heatsink. Solder to large pads or the circuit board ground plane to
maximize thermal dissipation.
Active-Low Shutdown Input. A logic low reduces the supply current to less than 1µA. Connect to IN for normal
operation.
Adjust (Input): Adjustable regulator feedback input. It can connect to an external resistor divider for adjustable output voltage. It also must connect ≥470pF ceramic capacitor from ADJ pin to GND for reduce
output noise.
Regulator Output. Fixed or adjustable from +2.5V to +5.5V. Sources up to 150mA. Bypass with a 1µF,
<0.2Ω typical ESR capacitor to GND.
Detailed Description
This equation is correct due to the configuration of the
bandgap reference. The bandgap voltage is relative to
the output, as seen in the block diagram. Traditional
regulators normally have the reference voltage relative
to ground and have a different VOUT equation. Resistor
values are not critical because ADJ (adjust)has a high
input impedance, but for best results use resistors of
470kΩ or less. A capacitor from ADJ to ground provides greatly improved noise performance.
The block diagram of the G914 is shown in Figure 1. It
consists of an error amplifier, 1.25V bandgap reference, PMOS output transistor, shutdown logic, over
current protection circuit, and over temperature protection circuit.
The G914 can be adjusted to a specific output voltage
by using two external resistors (Figure 2). The resistors set the output voltage based on the following
equation:
R2
VOUT =1.250V X
+1
R1
IN
SHDN
SHUTDOWN
LOGIC
ERROR
AMP.
+
OVER TEMP. &
OVER CURRENT
PROTECTION
OUT
1.25V
ref
ADJ
GND
Figure 1. Functional Diagram
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G914
Global Mixed-mode Technology Inc.
OUT
IN
of the chosen package to the ambient air. In the case
of a SOT23-5 package, the thermal resistance is typically 220oC/Watt.
OUTPUT
VOLTAGE
R1
+
The die attachment area of the G914’s lead frame is
connected to pin 2, which is the GND pin. Therefore,
the GND pin of G914 can carry away the heat of the
G914 die very effectively. To improve the power dissipation, connect the GND pin to ground using a large
ground plane near the GND pin.
G914
ADJ
- BATTERY CIN
1µF
SHDN
GND
COUT
1µF
R2
RL
470pF
Applications Information
Figure 2. Adjustable Output Using External
Feedback Resistors
Capacitor Selection and Regulator Stability
Normally, use a 1µF capacitor on the input and a 1µF
capacitor on the output of the G914. Larger input capacitor values and lower ESR provide better supply-noise rejection and transient response. A highervalue input capacitor (10µF) may be necessary if large,
fast transients are anticipated and the device is located several inches from the power source.
Over Current Protection
The G914 use a current mirror to monitor the output
current. A small portion of the PMOS output transistor’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 reference voltage. Once the output current exceeds the
limit, the PMOS output transistor enters constant current mode. The current is set to 370mA typically.
Power-Supply Rejection and Operation from Sources
Other than Batteries
The G914 is designed to deliver low dropout voltages
and low quiescent currents in battery powered systems. Power-supply rejection is 42dB at low frequencies.
Over Temperature Protection
To prevent abnormal temperature from occurring, the
G914 has a built-in temperature monitoring circuit.
When it detects the temperature is above 150oC, the
output transistor is turned off. When the IC is cooled
down to below 135oC, the output is turned on again. In
this way, the G914 will be protected against abnormal
junction temperature during operation.
When operating from sources other than batteries,
improve supply-noise rejection and transient response
by increasing the values of the input and output capacitors, and using passive filtering techniques.
Load Transient Considerations
The G914 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 0mA to 100mA is
12mV. Increasing the output capacitor's value and
decreasing its ESR attenuates transient spikes.
Shutdown Mode
When the SHDN pin is connected a logic low voltage,
the G914 enters shutdown mode. All the analog circuits 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 discharged to ground through the internal resistor voltage
divider.
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. Because the G914 use a P-channel MOSFET pass transistor, their dropout voltage is a function of RDS(ON)
multiplied by the load current.
Operating Region and Power Dissipation
Since the G914 is a linear regulator, its power dissipation is always given by P = IOUT (VIN – VOUT). The
maximum power dissipation is given by:
PD(MAX) = (TJ–TA)/θJA,=150oC-25oC/220oC/W= 568mW
Where (TJ–TA) is the temperature difference the G914
die and the ambient air,θJA, is the thermal resistance
TEL: 886-3-5788833
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Ver 0.1 Preliminary
Nov 05, 2001
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Global Mixed-mode Technology Inc.
Layout Guide
An input capacitance of ≅ 1µF is required between the
G914 input pin and ground (the amount of the capacitance 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.
G914
routing 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
routing wire. Figure 3 is suggested PCB layout of
G914.
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
Figure 3. Suggested PCB Layout
*Distance between pin & capacitor must no more than 1cm
TEL: 886-3-5788833
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Ver 0.1 Preliminary
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G914
Global Mixed-mode Technology Inc.
Package Information
C
D
L
E
H
θ1
e1
e
A
A2
A1
b
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
SYMBOLS
DIMENSIONS IN MILLIMETERS
NOM
MIN
A
A1
A2
b
C
D
E
e
e1
H
L
θ1
1.00
0.00
0.70
0.35
0.10
2.70
1.40
--------2.60
0.37
1º
1.10
----0.80
0.40
0.15
2.90
1.60
1.90(TYP)
0.95
2.80
-----5º
MAX
1.30
0.10
0.90
0.50
0.25
3.10
1.80
--------3.00
----9º
Taping Specification
Feed Direction
SOT23-5 Package Orientation
TEL: 886-3-5788833
http://www.gmt.com.tw
Ver 0.1 Preliminary
Nov 05, 2001
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