HA16129FPJ Datasheet | Hitachi Semiconductor

Description The HA16129FPJ is a watchdog timer IC that monitors a microprocessor for runaway. In addition to the watchdog timer function, the HA16129FPJ also provides a function for supplying a high-precision stabilized power supply to the microprocessor, a power on reset function, a power supply voltage monitoring function, and a fail-safe function that masks the microprocessor outputs if a runaway is detected. Functions - Watchdog timer (WDT) function Monitors the P-RUN signal output by the microprocessor, and issues an auto-reset (RES ) signal if a microprocessor runaway is detected. - Stabilized power supply Provides power to the microprocessor. - Power on and clock off functions The power on function outputs a low level signal to the microprocessor for a fixed period when power is first applied. The clock off function outputs a RES signal to the microprocessor a fixed period after a runaway occurs. - Power supply monitoring function When the reference voltage (Vout) falls and bees lower than the NMI detection voltage (4.63V, Typ) or the STBY detection voltage (3.0V Typ), this function outputs either an NMI signal or an STBY signal, respectively. Note that NMI detection can be set to monitor either V CC or Vout. - OUTE function- 1 (fail-safe function) Outputs a signal used to mask microprocessor outputs when a microprocessor runaway has been detected. - RES delay function Sets the delay between the time the NMI signal is output and the time the RES signal is output. - Protection functions The HA16129FPJ incorporates both Vout overvoltage prevention and current limiter functions. Note: 1. OUTE function: OUTE is an abbreviation for output enable. Features - - - - - High-precision output voltage: 5.0V ± 1.5% The WDT supports both frequency and duty detection schemes. High-precision power supply monitoring function: 4.625V ± 0.125V Built-in OUTE function All functions can be adjusted with external resistors and/or capacitors. Pin Arrangement P-RUN Rf...