Two-rail supervisor with configurable thresholds
The LTC2905IDDB#TRMPBF monitors two supply rails and asserts an active-low reset when either falls below its programmed threshold. Nine selectable threshold combinations cover common voltage pairs without external resistor dividers. The open-drain output stays low for a minimum of 140 ms after both rails recover, giving the downstream MCU or FPGA time to stabilize its internal regulators and clock before release. That minimum timeout is the number to design around for your system's power-on reset hold time. Industrial temperature range (-40°C to 85°C) covers factory automation, telecom infrastructure, and outdoor base station equipment.
Package and layout considerations
Housed in an 8-lead DFN with exposed pad (3 mm × 2 mm body), the LTC2905IDDB#TRMPBF requires a thermal via pattern under the pad for proper soldering and heat transfer. The exposed pad is typically tied to ground on the PCB. Surface-mount assembly is standard, but the small pitch means solder paste stencil aperture should match the datasheet land pattern recommendation to avoid bridging.
Lifecycle and sourcing
No end-of-life notice or last-time-buy window has been announced. For current BOMs, the LTC2905IDDB#TRMPBF can be specified into new designs without near-term LTB risk.