1
TC54
VOLTAGE DETECTOR
FEATURES
s
s
s
s
s
Precise Detection Thresholds .... Standard
±
2.0%
Custom
±
1.0%
Small Packages ........... SOT-23A-3, SOT-89, TO-92
Low Current Drain ..................................... Typ. 1
µ
A
Wide Detection Range .......................... 2.1V to 6.0V
Wide Operating Voltage Range ............ 1.5V to 10V
GENERAL DESCRIPTION
The TC54 Series are CMOS voltage detectors, suited
especially for battery-powered applications because of their
extremely low 1µA operating current and small surface-
mount packaging. Each part is laser trimmed to the desired
threshold voltage which can be specified from 2.1V to 6.0V,
in 0.1V steps.
The device includes a comparator, low-current high-
precision reference, laser-trimmed divider, hysteresis circuit
and output driver. The TC54 is available with either an open-
drain or complementary output stage.
In operation, the TC54's output (V
OUT
) remains in the
logic HIGH state as long as V
IN
is greater than the
–
specified threshold voltage (V
DET
). When V
IN
falls below
V
–
, the output is driven to a logic LOW. V
OUT
remains
DET
LOW until V
IN
rises above V
–
DET
by an amount V
HYST
,
whereupon it resets to a logic HIGH.
2
3
APPLICATIONS
s
s
s
s
s
Battery Voltage Monitoring
Microprocessor Reset
System Brownout Protection
Switching Circuit in Battery Backup
Level Discriminator
PIN CONFIGURATIONS
*SOT-23A-3
VIN
2
1 2 3
4
SOT-89-3
TO-92
ORDERING INFORMATION
PART CODE TC54 V X XX X X X XX XXX
Output form:
N = Nch Open Drain
C = CMOS Output
Detected Voltage:
Ex: 21 = 2.1V; 60 = 6.0V
Extra Feature Code:
Fixed: 0
Tolerance:
1 =
±
1.0% (custom)
2 =
±
2.0% (standard)
TC54VC only
TC54
3
VSS
TC54
1
VOUT
2
VIN
3
VSS
TC54
1
VOUT
5
VOUT
*SOT-23A-3 is equivalent to EIAJ (SC-59)
VIN
VSS
FUNCTIONAL BLOCK DIAGRAM
2
VIN
6
Temperature:
E: – 40°C to + 85°C
Package Type and Pin Count:
CB: SOT-23A-3*, MB: SOT-89-3, ZB: TO-92-3
–
+
VOUT
1
Taping Direction:
Standard Taping
Reverse Taping
No suffix: TO-92 Bulk
*SOT-23A-3 is equivalent to EIAJ (SC-59).
7
VREF
VSS
3
TC54VN has open-drain output.
TC54VC has complementary output.
TC54-10 11/8/96
8
4-279
TELCOM SEMICONDUCTOR, INC.
VOLTAGE DETECTOR
TC54
ABSOLUTE MAXIMUM RATINGS*
Supply Voltage (V
IN) .....................................................................
12V
Output Voltage: CMOS ............ (V
SS
– 0.3) to (V
IN
+ 0.3)
Open Drain ................. (V
SS
– 0.3) to 12V
Output Current .........................................................50mA
Power Dissipation: (T
A
≤
70°C)
SOT-23A-3 .....................................................240mW
SOT-89-3 .......................................................400mW
TO-92
.......................................................440mW
Operating Temperature .......................... – 40°C to + 85°C
Storage Temperature ........................... – 65°C to + 150°C
Soldering Temperature ...................... 300°C, 10 seconds
* Static-sensitive device. Unused devices must be stored in conductive
material. Protect devices from static discharge and static fields. Stresses
above those listed under Absolute Maximum Ratings may cause perma-
nent 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 operational sections of the specifications is not implied.
Exposure to Absolute Maximum Rating Conditions for extended periods
may affect device reliability.
ELECTRICAL CHARACTERISTICS:
T
A
= 25°C, unless otherwise specified.
Symbol
V
IN
I
SS
Parameter
Operating Voltage
Quiescent Current
Test Conditions
V
–
= 2.1 to 6.0V
DET
V
IN
= 2.1V
3.0V
4.0V
5.0V
Min
1.5
Typ
1.0
1.3
1.6
2.0
Max
10.0
3.0
3.4
3.8
4.2
(V
–
)
DET
x 1.02
(V
–
)
DET
x 0.08
Unit
V
µA
–
V
DET
Threshold Voltage
Hysteresis Range
Output Current
Nch V
DS
= 0.5
V
IN
= 2.1V
3.0V
4.0V
5.0V
V
IN
= 8.0V
V
HYST
I
OUT
(V
–
)
DET
x 0.98
(V
–
)
DET
x 0.02
V
V
mA
(V
–
)
DET
x 0.05
7.7
10.1
11.5
13.0
– 10.0
±
100
–
T
C
(V
DET
)
–
Tempco of (V
DET
)
Pch V
DS
= 2.1V
– 40°C
≤
T
A
≤
85°C
ppm/°C
PIN DESCRIPTION
Pin No.
1
2
3
Symbol
V
IN
V
OUT
V
SS
Description
Analog input. This pin is both the power supply input and the voltage to be monitored.
–
Digital output. This output goes low when V
IN
drops below V
DET
and returns
–
high when V
IN
rises above V
DET
+ V
HYST
. (See timing chart).
Ground terminal.
4-280
TELCOM SEMICONDUCTOR, INC.
VOLTAGE DETECTOR
1
TC54
DESCRIPTION OF OPERATION
TIMING CHART
VIN
+
VDET
VHYST
RELEASE
RESET
OR
VOLTAGE
VOLTAGE
–
DETECT VOLTAGE VDET
MINIMUM OPERATING
VOLTAGE
GROUND LEVEL
OUTPUT VOLTAGE
GROUND LEVEL
Refer to the Timing Chart below. In normal steady-state
–
operation, when V
IN
> V
DET
, the output will be at a logic high.
In the case of the TC54V, this is an open-drain condition. If
–
and when the input falls below V
DET
, the output will pull down
(Logic 0) to V
SS
. Generally, V
OUT
can pull down to within
0.5V of V
SS
at rated output current and input voltage. (See
the Electrical Characteristics section).
The output, V
OUT
, will stay valid until the input voltage
falls below the Minimum Operating Voltage, V
IN
(MIN), of
1.5V. Below this minimum operating voltage, the output is
undefined. During power-up or anytime V
IN
has fallen below
V
IN
(MIN), V
OUT
will remain undefined until V
IN
rises above
V
IN
(MIN), at which time the output will become valid. V
OUT
+
will be in its active low state while V
IN
(MIN) < V
IN
< V
DET
.
–
(V
+
= V
DET
+ V
HYST
). If and when the input rises above
DET
V
+
, the output will assume its inactive state. (High for
DET
TC54VC, open-drain for TC54VN).
2
3
4
APPLICATIONS
Refer to TelCom Semiconductor Application Note #2,
Using the TC54 Voltage Detector.
MARKING
SOT-23A-3
SOT-89-3
TO-92
5
1 2 3 4
5 6 7 8
9 10 11 12
6
= output (Nch or CMOS) plus first voltage digit
2 3 4 5 6
Nch
M N P R S
CMOS
C D E F H
D
ex: CMOS 3.x =
kkkk
= first voltage decimal (0-9)
D 4
ex: CMOS 3.4 =
kkkk
&
= assembly lot number
,
&
= 54_ (fixed)
= output (C = CMOS, N = Nch)
= first voltage digit (2-6)
= first voltage decimal (0-9)
= extra feature code : fixed : 0
= detecting accuracy
1 =
±
1.0% (custom), 2 =
±
2.0% (standard)
,
,
&
= assembly lot number
7
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TELCOM SEMICONDUCTOR, INC.
4-281
