TelCom Semiconductor Inc TC32MEZB, TC32MEDB, TC32MCZB, TC32MCDB Datasheet
TC32M
ECONOMONITOR™ – 3-PIN SYSTEM SUPERVISOR WITH POWER
SUPPLY MONITOR AND WATCHDOG
FEATURES
GENERAL DESCRIPTION
1
2
■ Incorporates the Functionality of the Industry
Standard TC1232 (Processor Monitor, Watchdog
and Manual Override RESET Controller) into a
Small, Lower Cost Package
■ Guards Against Unstable Processor Operation
Resulting from Power "Brown-Out"
■ Automatically Halts and Restarts an Out-of-
Control Microprocessor
■ Output can be Wire-ORed, or Hooked to Manual
RESET Push-button Switch
■ Space-Saving 3-Pin TO-92 or SOT-223 Package
APPLICATIONS
■ All Microprocessor-Based Systems
■ Battery Powered Computers and Controllers
■ Automotive Systems
■ Intelligent Instruments
■ Critical Processor Monitoring
■ Embedded Controllers
PIN CONFIGURATIONS
TO-92
DD
V
GND
RS
1
23
TC32MCZB
TC32MEZB
SOT-223
V
DD
TC32MCDB
TC32MEDB
1
V
GND
4
2
DD
3
RS
The TC32M is a fully-integrated processor supervisor in
a 3-pin package. It provides three important functions to
safeguard processor sanity: precision power on/off RESET
control, watchdog timer and external RESET override.
On power-up, the TC32M holds the processor in the
reset state for a minimum of 500msec after VDD is within
tolerance to ensure a stable system start-up. Microprocessor sanity is monitored by the on-board watchdog circuit.
The microprocessor must provide a high-to-low level shift
(through an external resistor divider) on the RS pin of the
TC32M. Should the processor fail to supply this signal within
the specified timeout period (typically 700msec), an out-ofcontrol processor is indicated and the TC32M issues a
processor reset as a result.
The output of the TC32M can be wire-ORed with a pushbutton switch (or electronic signal) to override the TC32M
and unconditionally reset the processor. When connected to
a push-button switch, the TC32M provides contact debounce.
The TC32M is packaged in a space-saving TO-92
or SOT-223 package. It provides all of the functionality of the
industry standard TC1232 in a smaller, lower cost configuration.
ORDERING INFORMATION
Temperature
Part No. Package Range
TC32MCDB SOT-223 0°C to +70°C
TC32MCZB TO-92 0°C to +70°C
TC32MEDB SOT-223 – 40°C to +85°C
TC32MEZB TO-92 – 40°C to +85°C
3
4
5
6
FUNCTIONAL BLOCK DIAGRAM
V
REF1
WATCHDOG
TIMER
TELCOM SEMICONDUCTOR, INC.
∆V
DETECTOR
V
REF2
DELAY
TIMER
V
DD
TC32M
RS
GND
TYPICAL OPERATING CIRCUIT
R1, 10k
R2,10k
RS
TC32M
RESET
MICROCONTROLLER EXAMPLE
5V
MICRO-
CONTROLLER
PO.1
RESET
7
8
TC32M-2 9/26/96
5-3
TC32M
ECONOMONITOR™ – 3-PIN SYSTEM SUPERVISOR
WITH POWER SUPPLY MONITOR AND WATCHDOG
ABSOLUTE MAXIMUM RATINGS *
Supply Voltage ........................................................ +6.0V
Input Voltage, Any Pin........ (GND – 0.3V) to (VDD + 0.3V)
Operating Temperature Range
TC32MC Package .................................0°C to +70°C
TC32ME Package ............................– 40°C to +85°C
* 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 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 operational sections of the specifications is not implied.
Exposure to Absolute Maximum Rating Conditions for extended periods
may affect device reliability.
Storage Temperature Range ................– 65°C to +150°C
Lead Temperature (Soldering, 10 sec) .................+300°C
RECOMMENDED OPERATING CONDITIONS, DC: T
Symbol Parameter Test Conditions Min Typ Max Unit
V
DD
V
IH
V
IL
ELECTRICAL CHARACTERISTICS, DC: V
Symbol Parameter Test Conditions Min Typ Max Unit
I
IL
I
OL
I
CC
V
STH
V
STL
V
RST
Supply Voltage 4.5 — 5.5 V
RS Input HIGH Level for PB 2.0 — — V
RS Input LOW Level for PB — — 0.3 V
= 4.5V to 5.5V; TA = – 40°C to 85°C, unless otherwise specified.
DD
RS Input Leakage – 1 — +1 µA
RS Output Current V
= 0.4V 2.0 10 — mA
OL
Operating Current Note 1 — 50 200 µA
RS Strobe HIGH Level Figure 1 (V
RS Strobe LOW Level Figure 1 2.00 — (V
RESET Threshold VDD Falling 4.25 — 4.50 V
(Note 2, Figure 3)
= – 40°C to +85°C, unless otherwise specified.
A
– 0.5) — — V
DD
– 1.5) V
DD
ELECTRICAL CHARACTERISTICS, CAPACITANCE: T
= 25°C, unless otherwise specified.
A
Symbol Parameter Test Conditions Min Typ Max Unit
C
IN
C
OUT
ELECTRICAL CHARACTERISTICS, AC: T
Input Capacitance — — 5 pF
Output Capacitance — — 7 pF
= – 40°C to +85°C, VDD = 5V ±10%, unless otherwise specified.
A
Symbol Parameter Test Conditions Min Typ Max Unit
t
RST
t
ST
t
TD
t
RPD
NOTES: 1. No output load.
2. All voltages referenced to ground.
RESET Active Time Figure 2 500 700 900 msec
RS STROBE Pulse Width Figure 1 500 — — nsec
Watchdog Timeout Period Figure 1 500 700 900 msec
VDD Detect to RS LOW Figure 3 — — 100 nsec
5-4
TELCOM SEMICONDUCTOR, INC.
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