FS8832<Preliminary>
150 mA Low Noise LDO Linear Regulator
General Description
The FS8832 is a low-noise, low-dropout linear
regulator that operates from 2.5V to 6.5V input
voltage range and delivers up to 150mA output
current. Typical output noise for the device is just
40µVRMS with an external capacitor connected to the
noise bypass pin to reduce the output noise level.
Typical dropout voltage is 240mV at 150mA.
Ordering Information
FS8832-xx x x
Package
A : SOT-23-5
C : Commercial Standard
P : Commercial Standard, Lead(Pb) Free
and Phosphorous(P) Free Package
Output Voltage
15 : 1.5V
16 : 1.6V
17 : 1.7V
18 : 1.8V
19 : 1.9V
20 : 2.0V
21 : 2.1V
22 : 2.2V
23 : 2.3V
24 : 2.4V
25 : 2.5V
26 : 2.6V
Features
z
z
z
z
z
z
27 : 2.7V
28 : 2.8V
29 : 2.85V
30 : 3.0V
31 : 3.1V
32 : 3.2V
33 : 3.3V
34 : 3.4V
35 : 3.5V
36 : 3.6V
37 : 3.7V
38 : 3.8V
39 : 3.9V
40 : 4.0V
41 : 4.1V
42 : 4.2V
43 : 4.3V
44 : 4.4V
45 : 4.5V
46 : 4.6V
47 : 4.7V
48 : 4.8V
49 : 4.9V
50 : 5.0V
Note : Output Voltage is preset at
2.5V, 2.85V, 3.0V or 3.3V,
and standard package type is
‘A’ type. Mask option output
voltages and ‘B’ package
type are available by special
order only.
Low output noise: 40µVRMS（Typ.）at 100mA
output current
Low 240mV dropout at 150mA output
High output voltage accuracy: ±35mV
Preset at 2.5V, 2.85V, 3.0V, 3.3V
Mask options from 1.5V to 5.0V
Low 70µA quiescent current（Typ.）
Logic control shutdown
Auto-discharge function
Output current limit
Thermal overload shutdown protection
SOT23-5 Package
Pin Configurations
Part
No.
Pin
1
Pin Pin Pin Pin
2
3
4
5
FS8832
IN GND EN BP OUT
-xxxA
FS8832
EN GND BP OUT IN
-xxxB
Applications
z
z
z
z
z
2.GND 3.EN
5.OUT
2.GND 3.NC
5.IN
Temperature Range
The FS8832 consists of a voltage reference, a
comparator, a P-channel pass transistor, and an
enable/disable logic circuit. Other features include
short-circuit
protection,
thermal
shutdown
protection, and auto-discharge function. The
auto-discharge function actively discharges the
output voltage to ground when the device is
placed in shutdown. The FS8853 devices are
available in SOT-23-5 package.
z
z
1.IN
4.NC
1.EN
4.OUT
B : SOT-23-5
The high-accuracy ( ± 35mV) output voltage is
preset at an internally trimmed voltage 2.5V,
2.85V, 3.0V or 3.3V. Other output voltages can be
mask-optioned from 1.5V to 5.0V with 100mV
increment, except FS8832-29Cx which has 2.85V
output voltage.
z
Pin Out
Cellular Telephones
Cordless Telephones
PCS Telephone
Wireless Handsets
Palmtop Computer
Fortune Semiconductor Corp.
http://www.fsc.com.tw
TEL : +886-2-2809-4742
FAX: +886-2-2809-4874
1/10
FS8832-DS-02_EN
Rev. 0.2
Mar. 2005
FS8832<Preliminary>
Package Marking Information
EX：FS8832-29PA
EX：FS8832-33CA
Top Point: Lot No.
Bottom Point: Year
w : week, A~Z & A ~ Z
A Dot After Marking : Pb/P Free
Top Point: Lot No.
Bottom Point: Year
w : week, A~Z & A ~ Z
Pin description
Part NO.
Symbol
IN
FS8832-xxxA
FS8832-xxxB
GND
Description
Regulator input.
Ground.
EN
Enable pin.
BP
An external bypass capacitor connect node.
Regulator voltage output.
OUT
IN is the regulator input. Supply voltage can range from 2.5V to 9.0V. Bypass with a 1µF capacitor to
GND.
GND provides the reference for all voltages. This pin also functions as a heat sink. Solder to a large
pad or the circuit-board ground plane to maximize power dissipation.
EN is the output voltage ON/OFF control pin. When in shutdown, OUT is driven low. It needs 2V supply
at En pin to active the chip. The EN pin input voltage must be less than the input voltage at IN pin.
BP is the reference-noise bypass. Bypass with a low-leakage, 0.01µF ceramic capacitor to reduce
noise at the output.
OUT is the output voltage. Sources up to 150mA. Bypass with a 3.3µF capacitor to GND
Fortune Semiconductor Corp.
2/10
Rev. 0.2
FS8832<Preliminary>
Typical Application Schematic
INPUT
2.5V
TO
9.0V
IN
OUT
3.3µF
1µF
GND
OFF
2V
ON
BP
EN
0.01µF
Function block diagram
IN
EN
Reverse
Battery
Protection
Current
Lim it
BP
Shutdown
Logic
Therm al
Protection
O UT
1.25V
Bandgap
Reference
G ND
Fortune Semiconductor Corp.
3/10
Rev. 0.2
FS8832<Preliminary>
Absolute Maximum Ratings
Input voltage VIN to GND ---------------------------------------------------------------------------------------------------- 10V
EN to GND ----------------------------------------------------------------------------------------------------------------------- VIN
Output short-circuit duration --------------------------------------------------------------------------------------- Continuous
Output current limit, I(LIMIT) ----------------------------------------------------------------------------------------------- 500mA
Continuous power dissipation, PD (∆T= TJ -TA = 100°C)
SOT-23-5 ----------------------------------------------------------------------------------------------------------------------------------------- 400mW
* The power dissipation values are based on the condition that junction temperature TJ and ambient
temperature TA difference is 100°C.
Junction Temperature, TJ ------------------------------------------------------------------------------------------------ +155°C
Storage temperature range, TSTG ----------------------------------------------------------------------- -55°C to +150°C
Operating junction temperature range ------------------------------------------------------------------ -40°C to +125°C
Lead temperature (soldering, 10sec) --------------------------------------------------------------------------------- 260°C
*
Stresses beyond those listed under “absolute maximum ratings” may cause permanent damage to the device. These
are stress ratings only, and function operation of the device at these or any other conditions beyond those indicated
under “recommended operating conditions” is not implied. Exposure to absolute-maximum-rated conditions for
extended periods may affect device reliability.
Fortune Semiconductor Corp.
4/10
Rev. 0.2
FS8832<Preliminary>
Electrical Characteristics
(VIN=5.0V, TA=0°C to +70°C, unless otherwise noted. Typical values are at TA=+25°C)
Symbol
Parameter
Test Conditions
Min
VIN
Input Voltage
2.5
VOUT0.035
150
Typ
Max
6.5
VOUT+
VOUT
0.035
Unit
V
VOUT
Output Voltage Accuracy
VIN=VOUT+1V, IOUT=30mA
IMAX
Maximum Output Current
VOUT+1V≦VIN
ILIMIT
Current Limit
IOUT=150mA
380
500
mA
VIN=VOUT+1V, IOUT=150mA
70
120
µA
VIN=VOUT+1V, No Load
70
120
µA
IOUT=1mA
1.6
2.5
mV
IOUT=50mA
80
125
mV
IOUT=150mA
240
375
mV
Vin=2.5V or (VOUT+0.4) to 6.5V,
IOUT=1mA
0.15
0.3
%/V
IOUT=150mA
0.01
0.02
%/mA
IQ
VDROP
∆VLINE
Ground Pin Current
Dropout Voltage
Line Regulation
∆VLOAD Load Regulation
eN
PSRR
VOUT=3.3V
V
mA
Output Noise
F=10Hz to 100KHz, CBP=0.01µF,
COUT=10µF, IOUT=100mA
40
µVRMS
PSRR
F=1KHz, COUT=3.3µF
60
dB
SHUTDOWN
ISD
Shutdown Supply Current
VOUT=0
VIH
Input Threshold High
2.5V<VIN<6.5V
0.01
VIL
Input Threshold Low
2.5V<VIN<6.5V
IEN
Input Bias Current
EN=IN or GND
Out Discharge Resistance
in Shutdown
EN=0V
1
2.0
µA
V
0.4
V
0.05
0.1
µA
300
600
Ω
THERMAL PROTECTION
TSD
THYS
θJA
Thermal Shutdown
Temperature
Thermal Shutdown
Hysteresis
Thermal Resistance
Fortune Semiconductor Corp.
155
°C
10
°C
SOT-23-5
250
°C/W
SOT-89-5
180
°C/W
5/10
Rev. 0.2
FS8832<Preliminary>
Typical Operating Characteristics
(VIN=+5.0V, CIN=1uF, COUT=3.3uF, CBP=0.01uF, TA=+25 ℃ , unless otherwise noted. Model name
FS8832-33CA)
DROPOUT VOLTAGE v.s LOAD CURRENT
OUTPUT VOLTAGE vs. INPUT VOLTAGE
800
3.5
700
DROPOUT VOLTAGE (mV)
OUTPUT VOLTAGE (V)
3
2.5
2
1.5
1
0.5
600
500
400
300
200
100
0
0
0
1
2
3
4
5
6
50
100
150
200
250
300
LOAD CURRENT (mA)
INPUT VOLTAGE (V)
OUTPUT CURRENT v.s Ron
OUTPUT VOLTAGE vs. TEMPERATURE
2.5
3.36
3.34
OUTPUT VOLTAGE (V)
Ron (Ω)
2
1.5
1
0.5
3.32
3.3
3.28
3.26
3.24
3.22
0
50
100
150
200
250
300
3.2
OUTPUT CURRENT (mA)
-40
-20
0
20
40
60
80
TEMPERATURE (℃)
POWER SUPPLY REJECTION RATIO vs FREQUENCY
GROUND PIN CURRENT vs INPUT VOLTAGE
90
60
80
PSRR(db)
50
40
30
20
10
0
-10
0.01
0.1
1
10
100
GROUND PIN CURRENT (uA)
70
FREQUENCY (KHz)
70
60
50
40
30
20
10
0
0
2.5
3
3.5
4
4.5
5
5.5
6
6.5
INPUT VOLTAGE (V)
Fortune Semiconductor Corp.
6/10
Rev. 0.2
FS8832<Preliminary>
GND PIN CURRENT vs. TEMPERATURE
GROUND PIN CURRENT vs LOAD CURRENT
72
GND PIN CURRENT (uA)
GROUND PIN CURRENT (uA)
68.5
68
67.5
67
66.5
66
65.5
70
68
66
64
62
65
64.5
60
-40
64
0
50
100
150
200
250
300
-20
0
20
40
60
80
TEMPERATURE (℃)
LOAD CURRENT (mA)
Load Transient, Load Current = 0mA -> 140mA
Line Transient, Vin=5V -> 6V
Output Noise, Load Current = 100mA
Output Noise, Load Current = 0mA
Fortune Semiconductor Corp.
7/10
Rev. 0.2
FS8832<Preliminary>
Detail Description
P-channel MOSFET output transistor between
pins VIN and VOUT is switched off, allowing
current consumption to be drastically reduced.
The VOUT pin enters the GND level due to the
several MΩ resistance of the feedback voltage
divider between VOUT and GND pins.
The FS8832 is a low-noise, low-dropout linear
regulator designed primarily for battery-powered
applications. The parts are available with preset
output voltages ranging from 1.5V to 5V, in
100mV increments. These devices can supply
loads up to 150mA. The FS8832 consists of a
1.25V bandgap reference, error amplifier,
P-channel pass transistor, and internal feedback
voltage divider.
Current Limit
The FS8832 also includes a fold back current
limiter. It monitors and controls the pass
transistor’s gate voltage, estimates the output
current, and limits the output current within
380mA (typical value).
The 1.25V bandgap reference is connected to
the error amplifier’s inverting input. The error
amplifier compares this reference with the
feedback voltage and amplifies the difference. If
the feedback voltage is lower than the reference
voltage, the pass-transistor gate is pulled lower,
which allows more current to pass to the output
and increases the output voltage. If the
feedback voltage is too high, the pass-transistor
gate is pulled up, allowing less current to pass to
the output. The output voltage is fed back
through an internal resistor voltage divider
connected to the OUT pin.
Output Voltage Selection
The FS8832 output voltage is preset at an
internally trimmed voltage 2.5V, 2.85V, 3.0V or
3.3V. The output voltage also can be
mask-optioned from 1.5V to 5.0V with 100mV
increment by special order. The first two digits of
part number suffix identify the output voltage
(see Ordering Information). For example, the
FS8832-33PA has a preset 3.3V output voltage.
An external bypass capacitor connected to the
BP pin reduces noise at the output. Additional
blocks include a current limiter, reverse battery
protection, thermal sensor, and shutdown logic.
The device also includes an auto-discharge
function, which actively discharges the output
voltage to ground when the device is placed in
shutdown mode.
Thermal-Overload Protection
Thermal-overload protection limits total power
dissipation in the FS8832. When the junction
temperature exceeds TJ = +155°C, the thermal
sensor signals the shutdown logic, turning off
the pass transistor and allowing the IC to cool.
The thermal sensor will turn the pass transistor
on again after the IC’s junction temperature
cools by 10°C, resulting in a pulsed output
during continuous thermal-overload conditions.
Internal P-Channel Pass Transistor
The FS8832 features a P-channel MOSFET
pass transistor. Unlike similar designs using
PNP pass transistors, P-channel MOSFETs
require no base drive, which reduces quiescent
current. PNP-based regulators also waste
considerable current in dropout when the pass
transistor saturates, and use high base-drive
currents under large loads. The FS8832 does
not suffer from these problems and consumes
only 70µA (Typ.) of current consumption under
heavy loads as well as in dropout conditions.
Thermal-overload protection is designed to
protect the FS8832 in the event of fault
conditions. For continuous operation, do not
exceed the maximum junction operating
temperature rating of TJ = +125°C.
Enable Function
EN pin starts and stops the regulator. When the
EN pin is switched to the power off level, the
operation of all internal circuit stops, the build-in
Fortune Semiconductor Corp.
8/10
Rev. 0.2
FS8832<Preliminary>
Operating Region and Power Dissipation
Larger input capacitor values and lower ESRs
provide better supply-noise rejection and
line-transient response. Reduce noise and
improve load-transient response, stability, and
power-supply rejection by using large output
capacitors. For stable operation over the full
temperature range and with load currents up to
150mA, a 1µF (min) ceramic capacitor is
recommended for VOUT ≥ 2.5V and 3.3µF and
for VOUT < 2.5V.
The FS8832’s maximum power dissipation
depends on the thermal resistance of the case
and circuit board, the temperature difference
between the die junction and ambient air, and
the rate of air flow. The power dissipation across
the device is P = IOUT (VIN - VOUT). The
maximum power dissipation is:
PMAX = (TJ - TA) / (θJC + θCA)
Note that some ceramic dielectrics exhibit large
capacitance and ESR variation with temperature.
With dielectrics such as Z5U and Y5V, it may be
necessary to increase the capacitance by a
factor of 2 or more to ensure stability at
temperatures below -10°C. With X7R or X5R
dielectrics, 1µF should be sufficient at all
operating temperatures for VOUT ≥2.5V.
where TJ - TA is the temperature difference
between the FS8832/FS8832A die junction and
the surrounding air, θJC is the thermal
resistance of the package, and θCA is the
thermal resistance through the printed circuit
board, copper traces, and other materials to the
surrounding air.
PSRR and Operation from Sources Other
than Batteries
The GND pin of the FS8832/FS8832A performs
the dual function of providing an electrical
connection to ground and channeling heat away.
Connect the GND pin to ground using a large
pad or ground plane.
The FS8832 are designed to deliver low dropout
voltages and low quiescent currents in
battery-powered
systems.
Power-supply
rejection is 60dB at low frequencies and rolls off
above 10kHz. See the Power-Supply Rejection
Ratio Frequency graph in the Typical
Operating Characteristics.
Reverse Battery Protection
The FS8832 have a unique protection scheme
that limits the reverse supply current to 1mA
when either VIN or Shutdown Voltage falls below
ground. Their circuitry monitors the polarity of
these two pins and disconnects the internal
circuitry and parasitic diodes when the battery is
reversed. This feature prevents device damage.
When operating from sources other than
batteries, improved supply-noise rejection and
transient response can be achieved by
increasing the values of the input and output
bypass capacitors, and through passive filtering
techniques.
The
Typical
Operating
Characteristics show the FS8832’s line- and
load-transient responses.
Noise Reduction
An external 0.01µF bypass capacitor at BP, in
conjunction with an internal 200kΩ resistor,
creates a 80Hz low-pass filter for noise
reduction. The FS8832 exhibits 40µVRMS of
output voltage noise with CBP = 0.01µF and
COUT = 10µF. This is negligible in most
applications. Start-up time is minimized by a
power-on circuit that pre-charges the bypass
capacitor.
Load-Transient Considerations
The FS8832 load-transient response graphs
(see Typical Operating Characteristics) show
two components of the output response: a DC
shift from the output impedance due to the load
current change, and the transient response.
Typical transient for a step change in the load
current from 0mA to 50mA is 12mV. Increasing
the output capacitor’s value and decreasing the
ESR attenuates the overshoot.
Applications Information
Capacitor Selection and Regulator Stability
Normally, use a 1µF capacitor on the FS8832’s
input and a 1µF to 10µF capacitor on the output.
Fortune Semiconductor Corp.
9/10
Rev. 0.2
FS8832<Preliminary>
Input-Output (Dropout) Voltage
determine the useful end-of-life battery voltage.
Because the FS8832 use a P-channel MOSFET
pass transistor, their dropout voltage is a
function of drain-to-source on-resistance
(RDS(ON)) multiplied by the load current (see
Typical Operating Characteristics).
For output voltage greater than the minimum
input voltage (2.5V), the regulator’s minimum
input-output voltage differential (or dropout
voltage) determines the lowest usable supply
voltage. In battery-powered systems, this will
Package information
SOT-23-5
Fortune Semiconductor Corp.
10/10
Rev. 0.2