Optoelectronics
Application Note
Voltage Regulator Information
INTRODUCTION
A voltage regulator maintains a specific stable DC
voltage despite input voltage fluctuation, load current,
and ambient temperature. They are a key component
in power supplies, motor drives, controllers, and anywhere a stable voltage is required.
Regulators are divided into two classes, each with
two sub-classes. Linear regulators are classified into
series regulators and shunt regulators. Linear regulators are widely used in audio equipment, VCRs, and
electronic musical instruments due to their their low ripple and low noise characteristics.
Switching regulators are classified into switching
type and converter type. Switching regulators are
widely used in medium and high power applications,
usually power supplies of more than 20 W, due to their
high efficiency. Sharp markets series regulators and
switching regulators.
SERIES REGULATOR CATEGORIES
Sharp’s series regulators are divided into two
types; NPN type and low drop-out PNP type. These
are available as fixed output voltage and variable output voltage types.
Sharp also offers added functionality such as ON/
OFF controls and reset signal generation. See Figure 1
for how each category breaks out.
3-TERMINAL
FIXED OUTPUT VOLTAGE
MULTI-FUNCTION
NPN
(4-TERMINAL)
(STANDARD)
3-TERMINAL
VARIABLE OUTPUT VOLTAGE
MULTI-FUNCTION
SERIES
REGULATORS
3-TERMINAL
FIXED OUTPUT VOLTAGE
MULTI-FUNCTION
PNP
(4/5-TERMINAL)
(LOW DROPOUT)
VARIABLE OUTPUT VOLTAGE
NOTE:
MULTI-FUNCTION
(4/5-TERMINAL)
SHARP Part
OP16-1
Figure 1. Series Regulator Tree
Application Note
1
Optoelectronics
Voltage Regulator Information
SWITCHING REGULATOR CATEGORIES
Switching regulators are divided into step-down/
polarity inversion type, and step-up type. They regulate
the output voltage by swiching the output on and off.
Since it’s not a linear circuit, the internal power losses
are extremely low. This makes them ideal for high wattage, high differential voltage applications. See Figure 2
for how each category breaks out.
LOW DROP-OUT REGULATOR
FEATURES
Sharp’s voltage regulators offer these features:
• Low drop-out: Low drop-out voltage
• Additional features are available: Built-in ON/OFF
control, precision adjustable output, variable voltage
output, low dissipation current when OFF, built-in
reset signal generation, and overheat shut-down
• Various packages:
– TO-92 (Lead forming type)
– TO-220 full-mold 4-terminal equivalent (Lead
forming type is also available.)
– TO-220 full-mold 5-terminal equivalent (Lead
forming type is also available.)
– TO-3P 5-terminal equivalent
– TO-263 (Tape-packaged products are also available.)
– SC-63 3-terminal equivalent (Tape-packaged
products are also available.)
– SC-63 5-terminal equivalent (Tape-packaged
products are also available.)
– SOT-89 equivalent (Tape-packaged products are
also available.)
– SOT-23L 6-terminal equivalent
– SOT-23-5 5-terminal equivalent
• Built-in protections: Overcurrent protection, overheat
protection, input-output reverse voltage protection
STEP-DOWN/POLARITY INVERSION
SWITCHING REGULATORS
STEP-UP
NOTE:
SHARP Part
OP16-2
Figure 2. Switching Regulator Tree
CONVENTIONAL REGULATOR
DROPOUT VOLTAGE 2.5 V MAX.
This input-output difference voltage
causes power loss and subsequent heat.
Reducing the dropout voltage carries positive effects.
SHARP’S LOW DROPOUT VOLTAGE REGULATOR
DROPOUT VOLTAGE 0.5 V MAX.
OP16-3
Figure 3. Reducing the Drop-out Voltage
2
Application Note
Voltage Regulator Information
Advantages of Low Drop-out Regulators
Low drop-out regulators offer these features:
• Smaller heat sinks due to lower power dissipation in
the device
• Smaller transformers (smaller cores) are required
since the input voltage can be reduced, plus the
higher frequencies are responsible for reducing size
as well
• Longer battery life
• Due to higher effeciencies, output current ratings per
package can be increased
• Overall design effeciency is increased
Additional Features
SHARP’s voltage regulators are also availble with
these features:
• ON/OFF control allows a power supply to operate in
stand-by mode or to switch off the main supply
• Precision output adjustment for variable output voltage devices; use two external resistors to precisely
set the output voltage
• Low current at OFF-state saves battery power
• Reset signal generation sends a specific-length
reset signal to the rest of the circuitry at switch-on, at
power interruption, or if the voltage drops, preventing
errors in MCU-based systems
• Overheat shut-down shuts down (crowbars) the output to prevent damage to downstream circuitry when
junction temperature ≥ 110°C. Once crowbarred, the
output is held OFF until a power supply reset or Vc
at the ON/OFF control terminal goes from LOW to
HIGH. This method is used in some devices; others
use Overheat protection.
Application Note
Optoelectronics
• Overheat protection shuts down the output to prevent
damage to downstream circuitry when junction temperature ≥ 125°C. As soon as the temperature drops
below this limit, output is automatically restored.
Some devices use this method of output protection;
others use Overheat shutdown.
• Overcurrent protection occurs when current exceeding the device’s rating flows to its output, as in the
case of a short-circuit. The output current will
instantly stabilize at a lower value.
• I/O reverse-voltage protection prevents damage to
the component when the output voltage exceeds the
input voltage.
NOTE: The component protection functions are designed to protect
the component itself and minimize damage to subsequent
circutry in the event of trouble. SHARP recommends designing circuitry around the Absolute Maximum Ratings rather
than the protection modes.
Packaging Features
SHARP’s devices have these features as part of
their packaging:
• Full-mold devices mean no need for an insulation
sheet between the device and the heat sink, therefore reduced production costs
• Full-mold devices may be placed close to adjacent
devices, improving safety
• Surface mount packages allow automatic high density mounting, and are available in tape-and-reel
configuations.
3
Optoelectronics
Voltage Regulator Information
USAGE AND MOUNTING TIPS
Electrical Tips
The bypass capacitors, CO, CIN must be connected to
ground with the shortest traces possible. The waveform
can be influenced by capacitor type, value, and ground
trace length. Variations in type and value of the capacitor
may cause it to oscillate (see Figure 7). The actual output waveform should be validated with production PCBs.
1
2
OP16-5
Figure 4. Input Protection Diode
Incorrect voltage or polarity can damage this device.
Ensure proper voltage tolerance and polarity before
applying power.
TO-3P Series
TO-220 Series
The ON/OFF control terminal is LSTTL-compatible. If
the ON/OFF control terminal is not used, tie it HIGH, but not
to the output; instead use a pull-up resistor if necessary.
3.7 mm MIN.
4.8 mm MIN.
When the DC input terminal is at ground potential,
during normal operation, charge can accumulate in the
output capacitor (CO), causing current flow to the input
side and damage the device. If the input terminal can
assume ground potential during normal operation, connect a protection diode as shown in Figure 4.
OP16-6
Figure 5. Lead Bending
Mechanical Tips
M3 FLAT FILLISTER HEAD SCREW
(do not use a countersink head screw)
LEAD FORMING
When forming leads, follow the specifications in
Figure 5 to keep mechanical stress from being applied
to the terminal and mold resin junction.
FLAT WASHER
When mounting a device to a heat sink, do not bend
the terminals during the mounting process.
For TO-220 devices, 0.4 to 0.5 N•m fastener torque
is recommended. For TO-3P devices, use 0.4 to 0.6
N•m fastener torque. Use an M3 fillister head screw. Do
not use a countersunk head screw. See Figure 6.
AL PLATE
SPRING WASHER
SURFACE MOUNTING
The standard mounting pattern for surface mount
type regulators appears in Figure 8. In actual use, the
trace must be suffient to meet the power dissipation
based on derating curve for the particular regulator.
M3 NUT
OP16-7
Figure 6. Fixed Mounting
VIN
VO
1
2
+
CO
4
LOAD
3
CMOS or TTL
OP16-4
Figure 7. Electrical Connections for TO-220 Series Devices
4
Application Note
Voltage Regulator Information
Optoelectronics
3-PIN SC-63 CASE
5-PIN SC-63 CASE
7.0
7.0
A
2.5
2.5
6.9
6.9
7.0
7.0
A
2.54
0.8
4 - 1.27
0.8
2.54
5.08
5.08
TO-263 CASE
10.0
2.35
2.35
R0.5
φ.1
9.9
9.5
8.4
φ.1
4.6
8.5
1.0
R0.5
1.2
1.2
3.0
1.2
0.60
0.60
0.75
0.75
4 - 1.7
6.8
NOTE: Dimensions are in mm.
OP16-11
Figure 8. Surface Mounting Pattern
Application Note
5
Optoelectronics
Voltage Regulator Information
Designing for Thermal Protection
When the thermal resistance of a heat sink is known:
Maximum power dissipation of devices is obtained
by the equation: PD = IO × (VIN – VO) + VIN × Iq
Tj = P × R'th (j – a) + Ta
Using the ambient temperature, Ta, and power dissipation, PD (MAX.), determine the heat sink area
required for safe operation within the Absolute Maximum specifications. Operating outside these temperature limits can result in degraded performance or
device failure.
On condition that:
= (Vi – O × IO) × R'th (j – a) + Ta
R'th (j – a) = Rth (j – c) + Rth (c – a)
Confirm Tj ≤TjMAX (125°C). Tj should be 70% to
80% of TjMAX.
HEAT SINK TIPS
Do not allow any warping or unevenness in the contact surface between the heat sink and device. Make
sure there are no burrs or shavings in the contact area.
Use of thermal shutdown circuits are recommended
to keep the device from exceeding the Absolute Maximum ratings.
HEAT SINK DESIGN
When the thermal resistance of a heat sink is
unknown:
Apply a recommended silicone grease uniformly to
the contact suface between the heat sink and device.
Recommended characteristics are:
Take the case temperature (TC) with a φ 0.1 mm
thermocouple between the device case and the heat
sink. Ambient temperature is the MAX temperature for
ordinary operating conditions.
• No general variation in operating temperature range.
• Base oil does not separate and it does not permeate
into the device.
• Even if base oil permeates into the device, operation
and lifetime are not influenced.
Tj = P × Rth (j – c) + Tc
= (Vi – O × IO) × Rth (j – c) + Tc
Some recommendations:
Confirm Tj ≤TjMAX (125°C). Tj should be 70% to
80% of TjMAX.
• G-746 from Shin-Etsu Chemical Co., Ltd.
• SC-102 from Dow Corning Toray Silicone Co., Ltd.
HEAT SINK THERMAL RESISTANCE AREA
(2 mm aluminum plate)
REGULATOR
THERMAL RESISTANCE RATIO (c-a) (°C/W)
100
HEAT SINK
10
5
DASHED LINE INDICATES
REGULATOR IS CENTERED ON HEAT SINK
1
10
50
100
1,000
HEAT SINK AREA (cm2)
OP16-8
Figure 9. Heat Sink Thermal Resistance
6
Application Note
Voltage Regulator Information
Optoelectronics
DESIGNING WITH LOW DROPOUT
VOLTAGE REGULATORS (SC-63 SERIES)
Thermal Protection
SHARP recommends these design practices to minimize any possibility of device or collateral circuitry
damage.
Electrical Connection
The bypass capacitors, CO and CIN must be connected to ground with the shortest traces possible. The
waveform can be influenced by capacitor type, value,
and ground trace length. The actual output waveform
should be validated with production PCBs.
Incorrect voltage or polarity can damage this device.
Ensure proper voltage tolerance and polarity before
applying power.
Maximum power dissipation (PD) of these devices
can be calculated with:
PD = IO × (VIN – VO)
Using the ambient temperature, Ta, and power dissipation, PD (MAX.), determine the heat sink area
required for safe operation within the Absolute Maximum specifications. Operating outside these temperature limits can result in degraded performance or
device failure.
Use of thermal shutdown circuits are recommended
to keep the device from exceeding the Absolute Maximum ratings.
VIN
VO
1
2
+
CIN
CO
LOAD
3
OP16-9
Figure 10. SC-63 Series External Connections
Application Note
7
Optoelectronics
Voltage Regulator Information
DESIGNING WITH LOW DROP-OUT VOLTAGE REGULATORS
(SOT-23L SERIES)
SHARP recommends these design practices to minimize any possibility of device or collateral circuitry
damage.
6
4
Electrical Connection
OP16-13
The bypass capacitors, CO and CIN must be connected to ground with the shortest possible traces. The
waveform can be influenced by capacitor type, value,
and ground trace length. The actual output waveform
should be validated with production PCBs.
Figure 11. Input Protection Diode
Thermal Protection
Maximum power dissipation (PD) of these devices
can be calculated with:
Incorrect voltage or polarity can damage this device.
Ensure proper voltage tolerance and polarity before
applying power.
PD = IO × (VIN – VO)
Using the ambient temperature, Ta, and power dissipation, PD (MAX.), determine the heat sink area
required for safe operation within the Absolute Maximum specifications. Operating outside these temperature limits can result in degraded performance or
device failure.
The ON/OFF control pin is compatible with LSTTL,
and can be directly driven by TTL, LSTTL, or CMOS
standard logic.
If voltage is applied to the output terminal which
exceeds the voltage of DC input terminal, the device
may be damaged.
Thermal shutdown circuits should be use so that the
device does not exceed Absolute Maximum ratings.
When the DC input terminal is at ground potential,
during normal operation, charge can accumulate in the
output capacitor (CO), causing current flow to the input
side and damage the device. If the input terminal can
assume ground potential during normal operation, con-
6
VIN
4
+
CIN
1
CO
3
2
5
LOAD
Cn
CMOS or TTL
OP16-12
Figure 12. SOT-23L Series External Connections
8
Application Note
Voltage Regulator Information
Optoelectronics
DESIGNING WITH SWITCHING
REGULATORS (PQ1CZ1)
Thermal Protection
Internal power dissipation (P) of the device is
obtained using this equation:
SHARP recommends these design practices to
minimize any possibility of device or collateral circuitry
damage.
P = ISW × VSAT × D + VIN × I
Where:
Electrical Connection
ISW = Average Current
Good printed circuit board layout and external wiring
practices are very important to keep noise low. Designers should also be on the lookout for induced noise
from wiring inductance.
D = Duty cycle
To minimuze inductance, traces should be thick and
short between large current diodes, input and output
capacitors, and terminals 1 and 2. Single-point grounding should be used for best results.
For Step down types:
VIN = Input voltage referenced to ground
I = Consumption current
Ton
Vo + Vf
D ( Duty ) = --------------------------- = ----------------------------------------T ( period ) Vin – Vsat + Vf
ISW (Average) = I (Output current)
If the output voltage is not as stable as desired, it can
be improved by adding a capacitor (from several nF to
several dozen nF) in parallel with external resistor R2.
For Polarity inversion types:
Ton
Vo + Vf
D ( Duty ) = --------------------------- = ---------------------------------------------------------T ( period ) Vin + Vo – Vsat + Vf
A high-switching-speed diode is recommended for
the catch-diode D because of its higher efficiency.
Select a diode with current rating at least 1.2 times
greater than maximum switching current.
1
Isw ( Average ) = ------------- × I
1–D
The output ripple voltage is highly dependent on the
ESR (Equivalent Series Resistor) of the output capacitor,
and can be minimized by selecting a Low ESR capacitor.
Where Vf = diode forward voltage
Using the ambient temperature, Ta, and power dissipation, PD (MAX.), determine the heat sink area
required for safe operation within the Absolute Maximum specifications. Operating outside these temperature limits can result in degraded performance or
device failure.
Inductors should not be operated beyond maximum
rated current to prevent saturation.
Thermal shutdown circuits should be used to keep
the device from exceeding Absolute Maximum ratings.
4
1
L
2
VO
5
+
+
VIN
CIN
3
CS
D
CO
R2
LOAD
R1
OP16-14
Figure 13. PQ1CZ1 External Connections
Application Note
9
Optoelectronics
Voltage Regulator Information
Vout Adjustment
ON/OFF CONTROL WITH SOFT STARTUP
For ON/OFF control with capacitor Cs, use a series
current limiting resistor to prevent destroying transistor
Tr by discharge current from Cs.
The output voltage can be adjusted by attaching
external resistors as shown in Figure 15.
Adjustable range is:
a. Step-down voltage type
APPLICATION CIRCUIT EXAMPLE
A multi-output switching power supply (using a fixed
output voltage regulator) is shown in Figure 16.
VO = Vref to 35 V
The maximum value is limited to 0.9 × (VIN – VSAT).
b.
Polarity inversion type
VO = -Vref to -30 V
VO is limited to (40 – VIN – VF) × VIN.
(V)
ON/OFF
TERMINAL VOLTAGE
Output voltage (VO) Vref × (1+R2/R1) (V)
ON/OFF Control Terminal
In the circuit in Figure 15, when the ON/OFF control
terminal is driven LOW by switching transistor Tr, the
output voltage may be turned OFF and the device
enters standby mode. Current at stand-by mode
becomes 400 µA (MAX.).
3.55
(VTHH)
DUTY DMAX
2.25
(VTHL)
DUTY 0%
1.4
(VTHON)
0
SOFT START
When capacitor C S is charged, the output pulse
gradually increases and output voltage will rise gradually (See Figure 14).
OFF- SOFT
STANDBY MODE STATE START
TIME
OP16-16
Figure 14. Soft Startup Voltages
4
1
IO
L
2
VO
5
R2
VIN
+
CIN
3
+
D
CS
Tr
LOAD
CO
R1
OP16-15
Figure 15. ON/OFF Terminal Control
10
Application Note
Voltage Regulator Information
LINE
FILTER
AC
INPUT
Optoelectronics
ON/OFF
CONTROL
DIODE
BRIDGE
+
INRUSH
CURRENT
CONTROL
CIRCUIT
_
LOW POWER-LOSS
VOLTAGE REGULATOR
+
_
POWER MOSFET
SWITCHING
CONTROL
CIRCUIT
DEVIATION
DETECTION
PHOTOCOUPLER
OP16-17
Figure 16. Power Supply Circuit
ESD (Electrostatic Discharge)
These devices employ a bipolar IC and may be damaged by electrostatic discharge. The precautions listed
here should be taken to avoid ESD damage.
• Use proper human ESD protection.
• Use a static-safe work area and static-safe handling
equipment.
• Use static-safe manufacturing methods, including
soldering methods.
Cleaning
When cleaning with solvent, the temperature must
be kept below 45° C and parts may not be immersed for
more than 3 minutes.
When cleaning with ultrasonic devices, use Ethyl
alcohol, Methyl alcohol, or Isoprophyl alcohol as the
solvent. Because cleaning conditions differ by bath
size, ultrasonic power output, cleaning time, and PCB
size, testing under actual manufacturing conditions is
recommended to determine optimum cleaning.
Before using alternative solvents, confirm that they
do not dissolve the package resin nor promote corrosion within the chip. Use of fluorocarbon type solvents
is internationally prohibited. Do not use solvents containing these substances.
REFLOW SOLDERING
The temperature profile shown in Figure 17 provides
general soldering guidlines for these devices. It is
important to note that package-specific guidelines are
found in the ‘Voltage Regulator Soldering and Cleaning
Information’ document. The heating profiles of these
devices allow for a maximum of two soldering applications. The temperature shown in the Figure is mesured
on the fin portion of the devices. When using reflow soldering, observe these requirements:
• Infrared lamps may not uniformly preheat the resin.
Ensure that the temperature profile in Figure 17 is
observed across the entire surface. See the devicespecific specifications for the exact temperature
measurements.
• The temperature rise during reflow should be 4°C
per second or less.
HAND SOLDERING
These devices are designed for reflow soldering and
hand soldering is not recommended. If hand soldering
is necessary, it should be performed at 260°C or less
(soldering iron tip temperature) and should only be
done once.
SHARP does not recommend mounting these
devices to a ceramic PWB.
Soldering
These devices are designed for reflow soldering
methods. If hand soldering is needed in an emergency,
follow the instructions outlined in ‘Hand Soldering’.
Application Note
11
Optoelectronics
Voltage Regulator Information
40 s
10 s
260°C
CRITICAL ZONE
TEMPERATURE
RAMP
UP
RAMP
DOWN
230°C
120 s
TS MAX.
180°C
150°C
25°C
TIME
OP16-10
Figure 17. Reflow Thermal Limits
TERMS AND SYMBOLS
Table 1. Terms and Symbols
SYMBOL
TERM
DEFINITION
Vin
DC input voltage
Vc
ON/OFF control terminal voltage Maximum allowable voltage applied to ON/OFF control terminal
Io
Output current
Maximum allowable output current (continuous) with a resistive load
PD
Power dissipation
Maximum power dissipation: There are two types, no heat sink (PD1) and infinite heat sink (PD2).
Tj
Junction temperature
Maximum junction temperature allowable during operation of a device
Topr
Operating temperature
Ambient temperature range ensuring normal function of a device
Tstg
Storage temperature
Ambient temperature range where deterioration of characteristic and reduction
of reliability do not occur during long term holding without input to a device
Tsol
Soldering temperature
Maximum temperature allowable in soldering. Required condition is time setting
Vr
Reset output applicable
voltage
Maximum rating applicable to reset signal output terminal
Vadj
Output minute adjustment terminal voltage or output adjustment
terminal voltage
Maximum rating applicable to output voltage adjusting terminal
VO–i
Input-output reverse voltage
Maximum reverse voltage between input and output
Bias supply voltage
Maximum DC input voltage between bias supply voltage and GND terminal
VB
Maximum DC input voltage applied across input terminals
Vadj
Error input voltage
Maximum voltage between Oadj and COM terminal
Vi–O
Input-output voltage
Maximum voltage between Vin and VOUT
VOUT
Output-COM voltage
Maximum reverse voltage applicable to VOUT terminal against COM terminal
ON/OFF control voltage
Maximum voltage between ON/OFF and COM terminal
Switching current
Maximum peak current between Vin and VOUT
Vc
ISW
12
Application Note
Voltage Regulator Information
Optoelectronics
ABSOLUTE MAXIMUM RATINGS
Terms and Symbols
Table 2. Terms and Symbols
SYMBOL
Vo
RegL
TERM
Output voltage
Load regulation
DEFINITION
Voltage applied across output terminals
Represents the fluctuation of output voltage with respect to fluctuation of load
current. When the load current changes from IO1 to IO2, and the output voltage changes from VO1 to VO2, the RegL is expressed (in percent) as:
Vo1 – Vo2
RegL = ------------------------------- × 100
Vo1
RegI
Line regulation
Represents the fluctuation of output voltage when the DC input voltage Vin
changes. When the DC input voltage changes from Vin1 to Vin2, and the output voltage changes from VO1 to VO2, RegI is expressed (in percent) as:
Vo1 – Vo2
RegI = ------------------------------- × 100
Vo1
TcVo
Temperature coefficient of output
voltage
Represents the fluctuation of output voltage when the device junction temperature changes. When the device junction temperature changes from Tj1 to Tj2,
and the output voltage changes from VO1 to VO2, TcVo is expressed (in percent) as:
( Vo2 – Vo1 )
1
TcVo = --------------------------------- × ------------------------ × 100
Vo ( Tj )
Tj2 – Tj1
Where Tj = 25°C
RR
Vi–o
Ripple rejection
Dropout voltage
Rate of reduction of AC voltage superposed on output voltage against input
AC voltage when the AC sine voltage (frequency of 120 Hz, voltage of 0.5
Vrms) is superposed on the specified DC input voltage Vi. Assuming that ei
(Vrms) and eo (Vrms) express the input AC wave component and output AC
wave component, respectively, RR is represented by:
ei
RR = 20 × log ------- ( dB )
eo
This represents the difference between DC input voltage Vin required for normal operation of a device and output voltage VO. Assuming that Vin1 and VO1
are DC input voltage and output voltage, respectively, in the case when Vin is
lowered and VO lowers by 5% below normal value (VO at specified Vin), Vi–o
is represented by:
Vi – o = Vin1 – Vo1 ( V )
VC(ON)
ON-state voltage for control
Output control voltage VC which must be applied between ON/OFF control terminal and GND which is necessary for normal output voltage VO. Even when
the ON/OFF control terminal is opened, the output voltage is in the ON-state.
(except the PQ05RA series, PQ05SZ series, and the PQ05TZ series)
IC(ON)
ON-state current for control
Current which flows into the ON/OFF control terminal when the specified ON
control voltage is applied to the ON/OFF control terminal.
VC(OFF)
OFF-state voltage for control
Output control voltage Vc which must be applied between ON/OFF control terminal and GND which is necessary to turn off
IC(OFF)
OFF-state current for control
Current which flows out from the ON/OFF control terminal when the specified
output OFF control voltage is applied to the ON/OFF control terminal
Vo(adj)
Output voltage minute adjustment Adjustable range of output voltage (Vo)
Vref
Reference voltage
Application Note
Voltage between output minute adjustment terminal and GND, voltage between output adjustment terminal and GND.
13
Optoelectronics
Voltage Regulator Information
ELECTRICAL CHARACTERISTICS
Table 3. Terms and Symbols
SYMBOL
TcVref
TERM
Temperature coefficient
of reference voltage
DEFINITION
Represents the fluctuation of reference voltage when the device junction temperature
changes. When the device junction temperature changes from Tj1 to Tj2, and reference voltage changes from Vref1 to Vref2, TcVref is expressed (in %/°C) as:
Vref2 – Vref1
100
TcVref = ------------------------------------- × -----------------------Vref ( Tj )
Tj2 – Tj1
Where Tj = 25°C
Vrl
LOW reset output voltage
Voltage between reset output and GND when reset signal is active and fixed current is
applied between reset output and GND
Vrt
Reset threshold voltage
Output voltage when reset output is active (LOW), turning down the output voltage (Vo)
Irlk
Reset output leak current
Current into reset output terminal when specified voltage is applied between reset output and GND
Iq
Quiescent current
Consumption current from the GND terminal when the specified input voltage is applied
between Vin and GND with no load
Iqs
Output OFF-state
dissipation current
Consumption current from the GND ternimal when the ON/OFF control terminal is
turned off and the specified input voltage is applied between Vin and GND
IB(I)
Bias inflow current
Current which flows into bias power supply terminal when the specified load, input voltage, and bias power supply voltage are applied
IB(L)
Bias limitation current
Maximum current which flows into bias power supply terminal within a rating
Ground current
Dissipation current which flows out from the GND terminal when no load, specified input voltage, and bias power supply voltage are applied
OFF-state bias power
supply voltage
Bias power supply voltage (VB) which should be applied to bias power supply terminal
which is nesessary to turn off output
Overheat shut-down
temperature
Device temperature to shut down output voltage (Vo)
Output saturation
voltage*
Voltage between Vin and Vout when output transistor is ON.
Ig
VB(OFF)
Tsd
V(sat)*
Efficiency (in percent) is expressed as:
Efficiency η
Vo × Io
η = ----------------------- × 100
Vin × Iin
NOTE: *Applicable to switching regulators.
14
Application Note
Voltage Regulator Information
Optoelectronics
SPECIFICATIONS ARE SUBJECT TO CHANGE WITHOUT NOTICE.
Suggested applications (if any) are for standard use; See Important Restrictions for limitations on special applications. See Limited
Warranty for SHARP’s product warranty. The Limited Warranty is in lieu, and exclusive of, all other warranties, express or implied.
ALL EXPRESS AND IMPLIED WARRANTIES, INCLUDING THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR USE AND
FITNESS FOR A PARTICULAR PURPOSE, ARE SPECIFICALLY EXCLUDED. In no event will SHARP be liable, or in any way responsible,
for any incidental or consequential economic or property damage.
NORTH AMERICA
EUROPE
JAPAN
SHARP Microelectronics of the Americas
5700 NW Pacific Rim Blvd.
Camas, WA 98607, U.S.A.
Phone: (1) 360-834-2500
Fax: (1) 360-834-8903
www.sharpsma.com
SHARP Microelectronics Europe
Division of Sharp Electronics (Europe) GmbH
Sonninstrasse 3
20097 Hamburg, Germany
Phone: (49) 40-2376-2286
Fax: (49) 40-2376-2232
www.sharpsme.com
SHARP Corporation
Electronic Components & Devices
22-22 Nagaike-cho, Abeno-Ku
Osaka 545-8522, Japan
Phone: (81) 6-6621-1221
Fax: (81) 6117-725300/6117-725301
www.sharp-world.com
TAIWAN
SINGAPORE
KOREA
SHARP Electronic Components
(Taiwan) Corporation
8F-A, No. 16, Sec. 4, Nanking E. Rd.
Taipei, Taiwan, Republic of China
Phone: (886) 2-2577-7341
Fax: (886) 2-2577-7326/2-2577-7328
SHARP Electronics (Singapore) PTE., Ltd.
438A, Alexandra Road, #05-01/02
Alexandra Technopark,
Singapore 119967
Phone: (65) 271-3566
Fax: (65) 271-3855
SHARP Electronic Components
(Korea) Corporation
RM 501 Geosung B/D, 541
Dohwa-dong, Mapo-ku
Seoul 121-701, Korea
Phone: (82) 2-711-5813 ~ 8
Fax: (82) 2-711-5819
CHINA
HONG KONG
SHARP Microelectronics of China
(Shanghai) Co., Ltd.
28 Xin Jin Qiao Road King Tower 16F
Pudong Shanghai, 201206 P.R. China
Phone: (86) 21-5854-7710/21-5834-6056
Fax: (86) 21-5854-4340/21-5834-6057
Head Office:
No. 360, Bashen Road,
Xin Development Bldg. 22
Waigaoqiao Free Trade Zone Shanghai
200131 P.R. China
Email: smc@china.global.sharp.co.jp
SHARP-ROXY (Hong Kong) Ltd.
3rd Business Division,
17/F, Admiralty Centre, Tower 1
18 Harcourt Road, Hong Kong
Phone: (852) 28229311
Fax: (852) 28660779
www.sharp.com.hk
Shenzhen Representative Office:
Room 13B1, Tower C,
Electronics Science & Technology Building
Shen Nan Zhong Road
Shenzhen, P.R. China
Phone: (86) 755-3273731
Fax: (86) 755-3273735
©2006 by SHARP Corporation
Reference Code SMA06001