2004 Microchip Technology Inc. DS21434G-page 1
TC54
Features
• Precise Detection Thresholds: Standard ±2.0%,
Custom ±1.0%
• Small Packages: 3-Pin SOT-23A, 3-Pin SOT-89,
TO-92 and 5-Pin SOT-23A (7.7V only)
• Low Current Drain: Typ. 1 µA
• Wide Detection Range: 1.1V to 6.0V and 7.7V
• Wide Operating Voltage Range: 0.7V to 10V
Applications
• Battery Voltage Monitoring
• Microprocessor Reset
• System Brown-Out Protection
• Switching Circuit in Battery Backup
• Level Discriminator
Functional Block Diagram
General Description
The TC54 series are CMOS voltage detectors that are
especially well suited for battery-powered applications
because of their extremely low 1 µA operating current
and small surface-mount packaging. Each part is laser-
trimmed to the desired threshold voltage, which can be
specified from 1.4V to 7.7V for a 2% tolerance and from
1.5V to 6.0V for a 1% tolerance.
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.
During 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
DET
–
, the output is driven to a logic-low. V
OUT
remains low until V
IN
rises above V
DET
–
by an amount
V
HYST
, whereupon it resets to a logic-high.
Package Types
V
OUT
TC54VC onl
V
SS
1
3
+
–
V
IN
2
TC54VN has open-drain output.
TC54VC has complementary output.
V
REF
1 32
V
IN
V
SS
V
OUT
TC54
3-Pin SOT-89
5
5-Pin SOT-23A
TC54
1
3
4
2
NC NC
Note: 3-Pin SOT-23A is equivalent to the
EIAJ SC-59
5-Pin SOT-23A is equivalent to the
EIAJ SC-74A. (7.7V ONLY)
3-Pin TO-92
12
3
V
SS
V
IN
V
OUT
V
IN
V
OUT
V
SS
3
12
TC54
3-Pin SOT-23A
V
IN
V
IN
V
SS
V
OUT
V
OUT
V
SS
Voltage Detector
