HA1835P/HA1848P
Watchdog Timer
Description
The HA1835P and HA1848P is a monolithic voltage regulator control designed for microcomputer systems. In addition to the voltage regulator, it include watchdog timer function and power-on reset function. These ICs can perform many function in various microcomputer systems with few external parts.
Features
• Regulated power supply control function Wide area of operational voltage; V CC = 6 V to 30 V Available external PNP-type transistor, suited to.
Watchdog Timer
HA1835P/HA1848P
Watchdog Timer
Description
The HA1835P and HA1848P is a monolithic voltage regulator control designed for microcomputer systems. In addition to the voltage regulator, it include watchdog timer function and power-on reset function. These ICs can perform many function in various microcomputer systems with few external parts.
Features
• Regulated power supply control function Wide area of operational voltage; V CC = 6 V to 30 V Available external PNP-type transistor, suited to any system power supply Built-in overcurrent limiter for external PNP-type transistor Output voltage can be adjusted exactry in the range from 4 V to 6 V • Watchdog timer Internal bandpass filter control circuit (pulse width detect type) and reset signal oscillator Fail-safe utility Bandpass filter characteristics can be set by external resister (Rf) and capacitance (Cf) • Automatic reset Automatic power-on reset Pulse generator characteristics can be set by external resistor (RR) and capacitance (CR) Alternative between RES and RES output
HA1835P/HA1848P
Pin Arrangement
RR CR P-RUN Rf Cf Vout GND 1 2 3 4 5 6 7 14 13 12 11 10 9 8 RES RES CS VCC VCONT Comp * Vadj
(Top View) Note: HA1848P: 9 pin is non connection.
Pin Functions
Pin No. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 Symbol RR CR P-RUN Rf Cf Vout GND Vadj Comp VCONT VCC CS RES * RES * Functions Reset pulse width depends on resistance connected to RR Recommended range: 100 k Ω to 1 M Ω Reset pulse width depends on cap.