TelCom Semiconductor Inc TC1054-2.5VCT, TC1055-2.7VCT, TC1055-2.5VCT, TC1054-5.0VCT, TC1055-5.0VCT Datasheet
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50mA CMOS LDO WITH SHUTDOWN
PRELIMINARY INFORMATION
AND ERROR OUTPUT
50mA CMOS LDO WITH SHUTDOWN AND ERROR OUTPUT
TC1054
TC1054
FEATURES
■ Zero Ground Current for Longer Battery Life
■ Very Low Dropout Voltage
■ Guaranteed 50mA Output
■ High Output Voltage Accuracy
■ Standard or Custom Output Voltages
■ Power-Saving Shutdown Mode
■ ERROR Output can be Used as a Low Battery
Detector, or Processor Reset Generator
■ Over-Current and Over-Temperature Protection
■ Space-Saving SOT-23A-5 Package
■ Pin Compatible Upgrades for Bipolar Regulators
APPLICATIONS
■ Battery Operated Systems
■ Portable Computers
■ Medical Instruments
■ Instrumentation
■ Cellular/GSMS/PHS Phones
■ Linear Post-Regulators for SMPS
■ Pagers
ORDERING INFORMATION
Output Junction
Part No. Voltage **(V) Package Temp. Range
TC1054-2.5VCT 2.5 SOT-23A-5* – 40°C to +125°C
TC1054-2.7VCT 2.7 SOT-23A-5* – 40°C to +125°C
TC1054-3.0VCT 3.0 SOT-23A-5* – 40°C to +125°C
TC1054-3.3VCT 3.3 SOT-23A-5* – 40°C to +125°C
TC1054-5.0VCT 5.0 SOT-23A-5* – 40°C to +125°C
NOTE: *SOT-23A-5 is equivalent to the EIAJ (SC-74A)
** Other output voltages available. Please contact TelCom
Semiconductor for details
PIN CONFIGURATION
V
OUT
ERROR
45
GENERAL DESCRIPTION
The TC1054 is a high accuracy (typically ±0.5%) CMOS
upgrade for older (bipolar) low dropout regulators. Designed specifically for battery-operated systems, the
TC1054’s CMOS construction eliminates wasted ground
current, significantly extending battery life. Total supply
current is typically 50µA at full load (
than in bipolar regulators
!).
TC1054 key features include ultra low noise operation,
very low dropout voltage (typically 100mV at full load) and
internal feed-forward compensation for fast response to
step changes in load. An error output (ERROR) is asserted
when the TC1054 is out-of-regulation (due to a low input
voltage or excessive output current). ERROR can be used
as a low battery warning or as a processor RESET signal
(with the addition of an external RC network). Supply current
is reduced to less than 1µA, and both V
are disabled when the shutdown input is low. The TC1054
incorporates both over-temperature and over-current protection.
The TC1054 is stable with an output capacitor of only
1µF and has a maximum output current of 50mA. For higher
output current regulators, please see the TC1055
(I
= 100mA) regulator and TC1107, TC1108 (I
OUT
300mA) data sheets.
TYPICAL APPLICATION
V
IN
1
V
IN
2
GND
34
SHDN
TC1054
20 to 60 times lower
and ERROR
OUT
5
V
OUT
1µF
1M
ERROR
OUT
V
OUT
ERROR
=
TC1054
(SOT-23A-5*)
2
GND
3
SHDN
TOP VIEW
1
V
IN
NOTE: *SOT-23A-5 is equivalent to the EIAJ (SC-74A)
TC1054-01 6/12/97
TelCom Semiconductor reserves the right to make changes in the circuitry and specifications of its devices
Shutdown Control
(from Power Control Logic)
1
PRELIMINARY INFORMATION
TC1054
50mA CMOS LDO WITH SHUTDOWN
AND ERROR OUTPUT
ABSOLUTE MAXIMUM RATINGS*
Input Voltage .................................................................7V
Output Voltage ............................. (– 0.3V) to (VIN + 0.3V)
Power Dissipation ....................Internally Limited (Note 7)
*Stresses above 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 above
those indicated in the operation sections of the specifications is not implied.
Exposure to Absolute Maximum Rating conditions for extended periods
may affect device reliability.
Operating Temperature Range ........ – 40°C < TJ < 125°C
Storage Temperature ............................– 65°C to +150°C
Maximum Voltage on Any Pin ............ VIN +0.3V to – 0.3V
Lead Temperature (Soldering, 10 Sec.)................+260°C
ELECTRICAL CHARACTERISTICS:
VIN = V
+ 1V, IL = 0.1mA, CL = 3.3µF, SHDN > VIH, T
OUT
= 25°C, unless otherwise noted.
A
BOLDFACE type specifications apply for junction temperatures of – 40°C to
+125°C.
Symbol Parameter Test Conditions Min Typ Max Units
V
IN
I
OUT
MAX
V
OUT
TC V
OUT
∆V
/∆V
OUT
IN
∆V
OUT/VOUT
– V
V
IN
OUT
I
GND
I
IN
I
INSD
R
OUT
PSRR Power Supply Rejection Ratio FRE ≤ 1kHz — 64 — dB
I
OUT
SC
∆V
/∆P
OUT
D
T
SD
∆T
SD
eN Output Noise IL = I
Input Operating Voltage — — 6.5 V
Maximum Output Current 50 —— mA
Output Voltage Note 1 VR – 2.5% VR ±0.5% VR + 2.5% V
V
Temperature Coefficient Note 2 — — — ppm/°C
OUT
40
Line Regulation (VR + 1V) < VIN < 6V — 0.01 0.05 %/V
Load Regulation IL = 0.1mA to I
OUT
MAX
— 0.5 — %
(Note 3)
Dropout Voltage IL = 0.1mA — 5 — mV
IL = 20mA — 65
IL = 50mA — 95
(Note 4)
Ground Pin Current IL = I
OUT
MAX,
(Note 5)
— 0 — µA
Supply Current SHDN = VIH, IL = 0 — 50 — µA
Shutdown Supply Current SHDN = 0V — — 0.05 µA
Output Resistance during Shutdown
Output Short Circuit Current V
SHDN < V
OUT
IL
= 0V — 200 450 mA
100 x VR160 x V
R
—kΩ
Thermal Regulation Note 6 — 0.04 — %W
Thermal Shutdown Die Temperature
— 160 — °C
Thermal Shutdown Hysteresis — 10 — °C
OUT
MAX
— 160 — µV
SHDN Input
V
IH
V
IL
SHDN Input High Threshold V
SHDN Input Low Threshold V
= 2.5V to 6.5V 45 — — %V
IN
= 2.5V to 6.5V — — 15 %V
IN
IN
IN
TC1054-01 6/12/97
2
50mA CMOS LDO WITH SHUTDOWN
AND ERROR OUTPUT
PRELIMINARY INFORMATION
TC1054
ELECTRICAL CHARACTERISTICS:
V
IN
= V
+ 1V, IL = 0.1mA, CL = 3.3µF, SHDN > VIH, T
OUT
= 25°C, unless otherwise noted.
A
Symbol Parameter Test Conditions Min Typ Max Units
ERROR Output
V
MIN
V
OL
V
TH
V
HYS
NOTES: 1. VR is the regulator output voltage setting. VR = 2.5V, 2.7V, 3.0V, 3.3V, 5.0V.
2. TC V
3. Regulation is measured at a constant junction temperature using low duty cycle pulse testing. Load regulation is tested over a load
4. Dropout voltage is defined as the input to output differential at which the output voltage drops 2% below its nominal value.
5. Ground pin current is the regulator pass transistor gate current. The total current drawn from the input supply is the sum of the load
6. Thermal Regulation is defined as the change in output voltage at a time T after a change in power dissipation is applied, excluding load
7. The maximum allowable power dissipation is a function of ambient temperature, the maximum allowable junction temperature and the
8. Hysteresis voltage is referenced by VR.
Minimum Operating Voltage 1.0 — — V
Output Logic Low Voltage 1mA Flows to ERROR — — 400 mV
ERROR Threshold Voltage See Figure 2 — 0.95 x V
R
—V
ERROR Positive Hysteresis Note 8 — 50 — mV
= V
OUT
OUT
V
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.
current, ground current and supply current (i.e. IIN = I
or line regulation effects. Specifications are for a current pulse equal to I
thermal resistance from junction-to-air (i.e. TA, TJ, qJA). Exceeding the maximum allowable power dissipation causes the device to
initiate thermal shutdown. Please see
MAX –
OUT
V
x
OUT
∆T
MIN
6
x 10
Thermal Considerations
SUPPLY
+ I
+ I
GND
section of this data sheet for more details.
).
LOAD
at VIN = 6V for T = 10msec.
LMAX
PIN DESCRIPTION
Pin No.
(SOT-23A-5) Symbol Description
1VINUnregulated supply input.
2 GND Ground terminal.
3 SHDN 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, ERROR is open circuited and supply current is reduced to 0.05 microamp
(typical).
4 ERROR Out-of-Regulation Flag. (Open drain output). This output goes low when V
by approximately – 5%.
5V
OUT
Regulated voltage output.
is out-of-tolerance
OUT
TC1054-01 6/12/97
3
PRELIMINARY INFORMATION
TC1054
50mA CMOS LDO WITH SHUTDOWN
AND ERROR OUTPUT
DETAILED DESCRIPTION
The TC1054 is a precision fixed output voltage regulator. (If an adjustable version is desired, please see the
TC1070 or TC1071 data sheets.) Unlike the bipolar regulators, the TC1054 supply current does not increase with load
current. In addition, V
tion at very low load currents (an important consideration in
RTC and CMOS RAM battery back-up applications).
Figure 1 shows a typical application circuit. The regulator is enabled any time the shutdown input (SHDN) is at or
above VIH, and shutdown (disabled) when SHDN is at or
below VIL. 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) and V
OUT
circuited.
1µF
BATTERY
Shutdown Control
(to CMOS Logic or Tie
to V
if unused)
IN
Figure 1. Typical Application Circuit
remains stable and within regula-
OUT
falls to zero volts and ERROR is open
1µF
C1
+
R1
1M
0.2µF
C2
V
OUT
BATTLOW
or RESET
V
IN
GND
TC1054VCT
C2 Requires Only
if ERROR is used as a
Processor RESET Signal
(See Text)
V
OUT
ERRORSHDN
V
Pull-up resistor R1 can be tied to V
, VIN or any other
OUT
voltage less than (VIN = 0.3V).
V
OUT
ERROR
V
TH
V
IH
V
OL
Figure 2. ERROR Output Operation
HYSTERESIS (V
HYS
)
Output Capacitor
A 1µF(min) capacitor from V
mended. The output capacitor should have an effective
series resistance of 5Ω or less, and a resonant frequency
above 1MHz. 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.
to ground is recom-
OUT
ERROR Open Drain Output
ERROR is driven low whenever V
lation 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
V
regardless of the programmed output voltage value
OUT
(e.g. ERROR = VOL at 4.75 (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 V
inactive when V
rises above VTH = V
OUT
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 C2 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.
TC1054-01 6/12/97
falls out of regu-
OUT
falls to VTH, and
OUT
.
HYS
Thermal Considerations
Thermal Shutdown
Integrated thermal protection circuitry shuts the regulator off when die temperature exceeds 160°C. The regulator
remains off until the die temperature drops to approximately
150°C.
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:
4
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