TI TPS3421EGDRYR

The TPS3420, TPS3421, and TPS3422 (TPS342x) are low-current, ultra-small, pushbutton reset timers. These devices use a long timing set delay to provide the required system reset while avoiding resets caused by brief button closures or key presses. This reset configuration also differentiates between software interrupts and hardware system resets.

The TPS3420 and TPS3421 monitor two inputs (PB1 and PB2) and assert an active-low reset pulse (RST) when both inputs are held low for the selected time delay. For the TPS3421, RST remains low for a factory-set fixed duration. For the TPS3420, RST remains low until one of the PBx inputs is released. Since both inputs are required to trigger a reset, a dedicated reset button is not necessary. The TPS3422 monitors a single input (PB1) and asserts an active-low reset pulse (RST) when PB1 is held low for the selected time delay.

The TPS342x features an open-drain output for wire-OR connection with other open-drain devices. With an operating voltage range of 1.6V to 6.5V and an operating temperature range of -40°C to +125°C, the TPS342x provides an accurate, space-saving, ultralow-power solution for system reset applications.

• Ultra-small package: 1.45mm x 1.00mm SON package
• Operating voltage range: 1.6V to 6.5V
• Single (TPS3422) or dual (TPS3420 and TPS3421) button inputs
• Low supply current: 250nA (typical)
• Dual-state logic, user-selectable input delay:
  • Example: 7.5s and 0s
  • Multiple timing options available
• Fixed timeout pulse for RST (TPS3421 and TPS3422): 400ms (typical)
  • Other timing options available upon request
• Active-low, open-drain output

• Smartphones
• Tablets
• Ultrabooks
• Gaming consoles
• Portable consumer products
• Navigation devices
• Consumer medical products
• Toys