S4242 Datasheet, PDF (1/16 Pages) Summit Microelectronics, Inc. – Dual Voltage Supervisory Circuit With Watchdog Timer

S4242/S42WD42/S4261/S42WD61
Dual Voltage Supervisory Circuit
With Watchdog Timer(S42WD61) (S42WD42)
FEATURES
• Precision Dual Voltage Monitor
– V_CC Supply Monitor
- Dual reset outputs for complex
microcontroller systems
- Integrated memory write lockout function
- No external components required
• Second Voltage Monitor Output
– Separate V_LOW output
– Generates interrupt to MCU
– Generates RESET for dual supply systems
- Guaranteed output assertion to V_CC - 1V
• Watchdog Timer (S42WD42, S42WD61)
– 1.6s
• Memory Internally Organized 2 x8
• Extended Programmable Functions
Available on SMS24
• High Reliability
– Endurance: 100,000 erase/write cycles
– Data retention: 100 years
OVERVIEW
The S42xxx are a precision power supervisory circuit. It
automatically monitors the device’s VCC level and will
generate a reset output on two complementary open drain
outputs. In addition to the VCC monitoring, the S42xxx also
provides a second voltage comparator input. This input
has an independent open drain output that can be wire-
OR’ed with the RESET I/O or it can be used as a system
interrupt.
The S42xxx also has an integrated 4k/16k-bit nonvolatile
memory. The memory conforms to the industry standard
two-wire serial interface. In addition to the reset circuitry,
the S42WD42/S42WD61 also has a watchdog timer.
BLOCK DIAGRAM
VCC
8
SCL ₆
SDA 5
NONVOLATILE
MEMORY
ARRAY
WRITE
CONTROL
PROGRAMMABLE
RESET PULSE
GENERATOR
2 RESET#
+
–
VSENSE 3
+
–
1.26V
4
GND
VTRIP
RESET
CONTROL
PROGRAMMABLE
WATCHDOG
TIMER
(S42WD42,
S42WD61)
UV
OV
2025 T BD 2.0
7 RESET
1 VLOW#
SUMMIT MICROELECTRONICS, Inc. • 300 Orchard City Drive, Suite 131 • Campbell, CA 95008 • Telephone [phone] • Fax [phone] • www.summitmicro.com
© SUMMIT MICROELECTRONICS, Inc. 2000
2025 6.0 4/17/00
Characteristics subject to change without notice
1