Dual 5V and 3.3V µP Power 
Supply Supervisors w/Manual Reset
– Push-Pull and Open-Drain Outputs
– Selectable Trip Point Tolerance

The IMP1834 supervisors simultaneously monitor both 3.3V and 5V power sources and issue reset signals when either supply is out of tolerance. When an out-of-tolerance condition is detected, the output-reset signal of the affected supply becomes active and resets the system microprocessor/microcontroller. On power-up and after the supply voltage returns to an in-tolerance condition, the reset signal remains active for approximately 350ms. This allows the power supply and system microprocessor to stabilize.

KEY FEATUREs
◆ Lower power, pin-compatible replacements for
   the Dallas DS1834 
   — 40% lower maximum supply current:
      30µA vs 50µA
◆ Monitor 5V and 3.3V supplies simultaneously
◆ 5V and 3.3V power-on reset 
◆ 350ms reset time
◆ Debounced pushbutton reset input 
◆ Push-Pull CMOS output 
   — IMP1834, IMP1834D
   — Eliminates external pull-up resistors
   — Active LOW (IMP1834), HIGH (IMP1834D)
◆ Open drain output 
   — IMP1834A
   — Active LOW
◆ Selectable 5V and 3.3V trip point tolerance
◆ Internal power drawn from highest input 
   voltage, 5V or 3.3V
◆ Precision temperature-compensated voltage
   reference and comparator
◆ Low-cost surface mount SO, compact 
   MicroSO and DIP packages
◆ Wide operating temperature, –40°C to +85°C