TELCOM TC1173

TC1173
300mA CMOS LDO with Shutdown, ERROR Output and Bypass
FEATURES
GENERAL DESCRIPTION
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The TC1173 is a precision output (typically ±0.5%)
CMOS low dropout regulator. Total supply current is typically 50µA at full load (20 to 60 times lower than in bipolar
regulators!).
TC1173 key features include ultra low noise operation
(plus optional Bypass input); very low dropout voltage
(typically 240mV at full load) and internal feed-forward
compensation for fast response to step changes in load. An
error output (ERROR) is asserted when the TC1173 is outof-regulation (due to a low input voltage or excessive output
current). ERROR can be set as a low battery warning or as
a processor RESET signal (with the addition of an external
RC network). Supply current is reduced to 0.05µA (typical)
and VOUT and ERROR fall to zero when the shutdown input
is low.
The TC1173 incorporates both over-temperature and
over-current protection. The TC1173 is stable with an output
capacitor of only 1µF and has a maximum output current of
300mA.
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Extremely Low Supply Current for Longer Battery
Life!
Very Low Dropout Voltage
Guaranteed 300mA Output
Standard or Custom Output Voltages
ERROR Output Can be Used as a Low Battery
Detector or Processor Reset Generator
Power-Saving Shutdown Mode
Bypass Input for Ultra-Quiet Operation
Over-Current and Over-Temperature Protection
Space-Saving MSOP Package Option
APPLICATIONS
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Battery-Operated Systems
Portable Computers
Medical Instruments
Instrumentation
Cellular / GSM / PHS Phones
Linear Post-Regulator for SMPS
Pagers
ORDERING INFORMATION
TYPICAL APPLICATION
1
C1
1µF
2
VOUT
VIN
GND
NC
8
3
4
NC
Bypass
CBYPASS
470pF
(Optional)
SHDN
ERROR
6
Package
TC1173-xxVOA
TC1173-xxVUA
8-Pin SOIC
8-Pin MSOP
Junction
Temp. Range
– 40°C to +125°C
– 40°C to +125°C
VIN
Available Output Voltages:
2.5, 2.8, 3.0, 3.3, 5.0
xx indicates output voltages
7
TC1173
Part
Number
R3
1M
Other output voltages are available. Please contact TelCom
Semiconductor for details.
5
ERROR
Shutdown Control
(from Power Control Logic)
PIN CONFIGURATION
MSOP
VOUT
GND
NC
Bypass
1
8
2
7
3
4
TC1173VUA
6
5
VIN
NC
SHDN
ERROR
SOIC
VOUT 1
8 VIN
GND 2
7 NC
NC 3 TC1173VOA 6 SHDN
Bypass 4
TC1173-2 2/2/00 TelCom Semiconductor reserves the right to make changes in the circuitry and specifications of its devices.
5 ERROR
300mA CMOS LDO With Shutdown,
ERROR Output, And Bypass
TC1173
ABSOLUTE MAXIMUM RATINGS*
Storage Temperature ............................ – 65°C to +150°C
Maximum Voltage on Any Pin ............ VIN +0.3V to – 0.3V
Lead Temperature (Soldering, 10 Sec.) ................ +300°C
Input Voltage .............................................................. 6.5V
Output Voltage ........................... (VSS – 0.3) to (VIN + 0.3)
Power Dissipation .................... Internally Limited (Note 7)
Operating Temperature .................... – 40°C < TJ < 125°C
*Absolute Maximum Ratings indicate device operation limits beyond damage may occur. Device operation beyond the limits listed in Electrical
Characteristics is not recommended.
ELECTRICAL CHARACTERISTICS: VIN = VOUT + 1V, IL = 0.1µA, CL = 3.3µF, SHDN > VIH, TA = 25°C, unless otherwise noted.
BOLDFACE type specifications apply for junction temperatures of – 40°C to +125°C
Symbol
Parameter
Test Conditions
VIN
IOUTMAX
VOUT
Input Operating Voltage
Maximum Output Current
Output Voltage
Note 1
∆VOUT/∆T
VOUT Temperature Coefficient
Note 2
∆VOUT/∆VIN
∆VOUT/VOUT
VIN – VOUT
Line Regulation
Load Regulation
Dropout Voltage (Note 4)
ISS1
ISS2
PSRR
IOUTSC
∆VOUT∆PD
eN
Supply Current
Shutdown Supply Current
Power Supply Rejection Ratio
Output Short Circuit Current
Thermal Regulation
Output Noise
(VR + 1V) < VIN < 6V
IL = 0.1mA to IOUTMAX (Note 3)
IL = 0.1mA
IL = 100mA
IL = 300mA
SHDN = VIH
SHDN = 0V
FRE ≤ 1kHz
VOUT = 0V
Note 5
F = 1kHz, COUT = 1µF,
RLOAD = 50Ω
Min
—
300
—
VR - 2.5%
—
Typ
VR
—
—
± 0.5%
Max
Units
6.0
—
—
VR + 2.5%
—
V
mA
V
—
—
—
—
—
—
—
40
0.05
0.5
20
80
240
50
0.05
60
550
0.04
260
45
—
—
—
—
15
%VIN
%VIN
1.0
—
—
—
—
—
0.95 x VR
50
—
400
—
—
V
mV
V
mV
—
—
—
ppm/°C
0.35
2.0
30
160
480
90
0.5
—
650
—
—
%
%
mV
µA
µA
dB
mA
V/W
nV/√Hz
SHDN Input
VIH
VIL
SHDN Input High Threshold
SHDN Input Low Threshold
ERROR Output
VMIN
VOL
VTH
VOL
Minimum Operating Voltage
Output Logic Low Voltage
ERROR Threshold Voltage
ERROR Positive Hysteresis
1mA Flows to ERROR
Note 7
NOTES: 1. VR is the user-programmed regulator output voltage setting.
2. TC VOUT = (VOUTMAX – VOUTMIN) x 10 6
VOUT x ∆T
3. Regulation is measured at a constant junction temperature using low duty cycle pulse testing. Load regulation is tested over a load range from 0.1mA
to the maximum specified output current. Changes in output voltage due to heating effects are covered by the thermal regulation specification.
4. Dropout voltage is defined as the input to output differential at which the output voltage drops 2% below its nominal value measured at a 1V differential.
5. Thermal Regulation is defined as the change in output voltage at a time T after a change in power dissipation is applied, excluding load
or line regulation effects. Specifications are for a current pulse equal to ILMAX at VIN = 6V for T = 10msec.
6. The maximum allowable power dissipation is a function of ambient temperature, the maximum allowable junction temperature, and the
thermal resistance from junction-to-air (i.e. TA, TJ, θJA). Exceeding the maximum allowable power dissipation causes the device to initiate
thermal shutdown. Please see Thermal Considerations section of this data sheet for more details.
7. Hysteresis voltage is referenced to VR.
TC1173-2
2/2/00
2
300mA CMOS LDO With Shutdown,
ERROR Output, And Bypass
TC1173
SHDN may be controlled by a CMOS logic gate, or I/O port
of a microcontroller. If the SHDN input is not required, it
should be connected directly to the input supply. While in
shutdown, supply current decreases to 0.05µA (typical),
VOUT falls to zero and ERROR is disabled.
DETAILED DESCRIPTION
The TC1173 is a fixed output, low drop-out regulator.
Unlike bipolar regulators, the TC1173 supply current does not
increase with load current. In addition, VOUT remains stable and
within regulation at very low load currents (an important consideration in RTC and CMOS RAM battery back-up applications).
TC1173 pin functions are detailed below:
ERROR Output
ERROR is driven low whenever VOUT falls out of regulation by more than – 5% (typical). This condition may be
caused by low input voltage, output current limiting, or
thermal limiting.
The ERROR threshold is 5% below rated VOUT regardless of the programmed output voltage value (e.g., ERROR
= VOL at 4.75V (typ) for a 5.0V regulator and 2.85V (typ) for
a 3.0V regulator). ERROR output operation is shown in
Figure 2. Note that ERROR is active when VOUT is at or
below VTH, and inactive when VOUT is above VTH + VH.
As shown in Figure 1, ERROR can be used as a battery
low flag, or as a processor RESET signal (with the addition
of timing capacitor C2). R1 x C3 should be chosen to
maintain ERROR below VIH of the processor RESET input
for at least 200msec to allow time for the system to stabilize.
Pull-up resistor R1 can be tied to VOUT, VIN or any other
voltage less than (VIN + 0.3V.)
PIN DESCRIPTIONS
Pin
No.
Symbol
1
2
3
4
VOUT
GND
NC
Bypass
5
ERROR
6
SHDN
7
8
NC
VIN
Description
Regulated voltage output
Ground terminal
No connect
Reference bypass input. Connecting a 470pF
to this input further reduces output noise.
Out-of-Regulation Flag (Open Drain Output). This output goes low when VOUT is outof-tolerance by approximately -5%.
Shutdown control input. The regulator is fully
enabled when a logic high is applied to this
input. The regulator enters shutdown when a
logic low is applied to this input. During
shutdown, output voltage falls to zero and
supply current is reduced to 0.05µA (typical).
No connect
Unregulated supply input
VOUT
VTH
Figure 1 shows a typical application circuit. The regulator is enabled any time the shutdown input (SHDN) is above
VIH, and shutdown (disabled) when SHDN is at or below VIL.
Hysteresis (VH)
ERROR
VIH
VOL
VOUT
1
C1
1µF
2
VOUT
VIN
GND
NC
4
NC
Bypass
CBYPASS
470pF
(Optional)
SHDN
ERROR
VIN
Output Capacitor
A 1µF (min) capacitor from VOUT to ground is recommended. The output capacitor should have an effective
series resistance of 5Ω or less. A 1µF capacitor should be
connected from VIN to GND if there is more than 10 inches
of wire between the regulator and the AC filter capacitor, or
if a battery is used as the power source. Aluminum electrolytic or tantalum capacitor types can be used. (Since many
aluminum electrolytic capacitors freeze at approximately –
30°C, solid tantalums are recommended for applications
operating below – 25°C.) When operating from sources
other than batteries, supply-noise rejection and transient
response can be improved by increasing the value of the
input and output capacitors and employing passive filtering
techniques.
7
TC1173
3
Figure 2: ERROR Output Operation
8
6
5
R3
1M
ERROR
Shutdown Control
(from Power Control Logic)
Figure 1: Typical Application Circuit
TC1173-2 2/2/00
3
300mA CMOS LDO With Shutdown,
ERROR Output, And Bypass
TC1173
Bypass Input
A 470pF capacitor connected from the Bypass input to
ground reduces noise present on the internal reference,
which in turn significantly reduces output noise. If output
noise is not a concern, this input may be left unconnected.
Larger capacitor values may be used, but results in a longer
time period to rated output voltage when power is initially
applied.
Equation 1 can be used in conjunction with Equation 2
to ensure regulator thermal operation is within limits. For
example:
GIVEN:
Thermal Considerations
Thermal Shutdown
Integrated thermal protection circuitry shuts the regulator off when die temperature exceeds 150°C. The regulator
remains off until the die temperature drops to approximately
140°C.
FIND:
PD ≈ (VINMAX - VOUTMIN)ILOADMAX
= [(3.0 x 1.1) - (2.7 x .995)]250 x 10-3
= 155mW
Maximum allowable power dissipation:
PD ≈ (TJMAX– TAMAX)
JA
PD ≈ (VINMAX – VOUTMIN)ILOADMAX
PD =
VINMAX =
VOUTMIN =
ILOADMAX =
worst case actual power dissipation
maximum voltage on VIN
minimum regulator output voltage
maximum output (load) current
= (125 – 55)
200
= 350mW
In this example, the TC1173 dissipates a maximum of
only 155mW; far below the allowable limit of 350mW. In a
similar manner, Equation 1 and Equation 2 can be used to
calculate maximum current and/or input voltage limits. For
example, the maximum allowable VIN is found by substituting the maximum allowable power dissipation of 350mW
into Equation 1, from which VINMAX = 4.1V.
Equation 1.
The maximum allowable power dissipation (Equation 2)
is a function of the maximum ambient temperature (TAMAX),
the maximum allowable die temperature (125°C), and the
thermal resistance from junction-to-air (JA). The 8-Pin
SOIC package has a JA of approximately 160°C/Watt,
while the 8-Pin MSOP package has a JA of approximately
200°C/Watt; both when mounted on a single layer FR4
dielectric copper clad PC board.
Layout Considerations
The primary path of heat conduction out of the package
is via the package leads. Therefore, layouts having a ground
plane, wide traces at the pads, and wide power supply bus
lines combine to lower JA and, therefore, increase the
maximum allowable power dissipation limit.
PDMAX = (TJMAX – TAMAX)
JA
Where all terms are previously defined.
Equation 2.
TC1173-2
2/2/00
1. Actual power dissipation
2. Maximum allowable dissipation
Actual power dissipation:
Power Dissipation
The amount of power the regulator dissipates is primarily a function of input and output voltage, and output current.
The following equation is used to calculate worst case actual
power dissipation:
Where:
VINMAX = 3.0V ± 10%
VOUTMIN = 2.7V ± 0.5%
ILOADMAX = 250mA
TJMAX = 125°C
TAMAX = 55°C
JA = 200°C/W
8-Pin MSOP Package
4
300mA CMOS LDO With Shutdown,
ERROR Output, And Bypass
TC1173
TYPICAL CHARACTERISTICS
2.00
10.0
RLOAD = 50Ω
COUT = 1µF
Noise (µV/√/ HZ)
0.008
0.006
0.004
0.002
1.80
LOAD REGULATION (%)
0.010
LINE REGULATION (%)
Load Regulation
Output Noise
Line Regulation
0.012
1.0
0.1
0.000
–0.002
20
40
60
0.0
0.01
80 100 120
0.80
0.60
1 to 100mA
0.40
1 to 50mA
0.01
10
1
100
0.00
–40 –20
1000
Supply Current
DROPOUT VOLTAGE (V)
80.0
70.0
60.0
50.0
85°C
0.30
70°C
0.25
40
60
80 100 120
VOUT vs. Temperature
3.075
125°C
0.35
20
TEMPERATURE (°C)
Dropout Voltage vs. Load Current
0.40
90.0
0
FREQUENCY (KHz)
100.0
SUPPLY CURRENT (µA)
1.20
1.00
VIN = 4V
ILOAD = 100µA
CLOAD = 3.3µF
3.025
VOUT (V)
0
TEMPERATURE (°C)
25°C
0.20
0°C
0.15
2.975
0.10
–40°C
0.05
40.0
–40 –20
0.00
0
20
40
60
80 100 120
TEMPERATURE (°C)
0
50
100
Power Supply Rejection Ratio
VOUT = 5V
–35dB R
LOAD = 50Ω
–40dB VINAC = 50mV p-p
–45dB
–50dB
COUT = 1µF
–55dB
–60dB
–65dB
–70dB
–75dB
–80dB
10
100
1K
10K
150
200
LOAD CURRENT (mA)
–30dB
PSRR (dB)
1 to 300mA
1.40
0.20
–0.004
–40 –20
100K 1M
FREQUENCY (KHz)
TC1173-2 2/2/00
1.60
5
250
300
2.925
–40 –20
0
20
40
60
80 100 120
TEMPERATURE (°C)
300mA CMOS LDO With Shutdown,
ERROR Output, And Bypass
TC1173
TAPE AND REEL DIAGRAMS
Component Taping Orientation for 8-Pin SOIC (Narrow) Devices
User Direction of Feed
User Direction of Feed
PIN 1
W
PIN 1
Standard Reel Component Orientation
for TR Suffix Device
P
Reverse Reel Component Orientation
for RT Suffix Device
Carrier Tape, Number of Components Per Reel and Reel Size
Package
8-Pin SOIC (N)
Carrier Width (W)
Pitch (P)
Part Per Full Reel
Reel Size
12 mm
8 mm
2500
13 in
Component Taping Orientation for 8-Pin MSOP Devices
User Direction of Feed
User Direction of Feed
PIN 1
W
PIN 1
Standard Reel Component Orientation
for TR Suffix Device
P
Reverse Reel Component Orientation
for RT Suffix Device
Carrier Tape, Number of Components Per Reel and Reel Size
Package
8-Pin MSOP
TC1173-2
2/2/00
Carrier Width (W)
Pitch (P)
Part Per Full Reel
Reel Size
12 mm
8 mm
2500
13 in
6
300mA CMOS LDO With Shutdown,
ERROR Output, And Bypass
TC1173
PACKAGE DIMENSIONS
8-Pin SOIC (Narrow)
PIN 1
.157 (3.99)
.150 (3.81)
.244 (6.20)
.228 (5.79)
.050 (1.27) TYP.
.197 (5.00)
.189 (4.80)
.069 (1.75)
.053 (1.35)
.010 (0.25)
.007 (0.18)
8° MAX.
.020 (0.51) .010 (0.25)
.013 (0.33) .004 (0.10)
.050 (1.27)
.016 (0.40)
8-Pin MSOP
PIN 1
.122 (3.10)
.114 (2.90)
.197 (5.00)
.189 (4.80)
.026 (0.65) TYP.
.122 (3.10)
.114 (2.90)
.043 (1.10)
MAX.
.016 (0.40)
.010 (0.25)
.008 (0.20)
.005 (0.13)
6° MAX.
.006 (0.15)
.002 (0.05)
.028 (0.70)
.016 (0.40)
Dimensions: inches (mm)
Sales Offices
TelCom Semiconductor, Inc.
1300 Terra Bella Avenue
P.O. Box 7267
Mountain View, CA 94039-7267
TEL: 650-968-9241
FAX: 650-967-1590
E-Mail: [email protected]
TC1173-2 2/2/00
TelCom Semiconductor, GmbH
Lochhamer Strasse 13
D-82152 Martinsried
Germany
TEL: (011) 49 89 895 6500
FAX: (011) 49 89 895 6502 2
7
TelCom Semiconductor H.K. Ltd.
10 Sam Chuk Street, Ground Floor
San Po Kong, Kowloon
Hong Kong
TEL: (011) 852-2350-7380
FAX: (011) 852-2354-9957