MOSFET-controller sequencer for multi-rail power-up
The LTC2926IGN#PBF is a MOSFET-controller power supply sequencer from Analog Devices, designed to manage the turn-on and turn-off order of multiple supply rails in a system. It controls external N-channel MOSFETs to sequence supplies between 2.9 V and 5.5 V, a range that covers common logic and I/O voltages in mixed-signal boards.
Supply rail and quiescent budget
The 2.5 mA supply current is the quiescent draw of the controller itself, not including the gate-drive charge delivered to the external MOSFETs during switching. In a system where the sequencer is always powered — such as a base-station card that must hold sequencing logic during a supply brownout — this 2.5 mA load sits on the always-on standby rail and factors into the system's sleep-mode power budget. The lower end at 2.9 V allows operation from a 3.3 V rail that has dropped due to IR drop or during a low-battery condition, as long as the supply stays above the undervoltage lockout threshold.
20-SSOP footprint and layout constraints
This is the standard narrow-body SSOP-20 footprint — the same land pattern used by many other Analog Devices and TI sequencers and supervisory ICs. The 0.025-inch pin pitch requires a fine-tip soldering iron for hand rework or a standard reflow profile for production. The surface-mount package sits flat on the board with no exposed pad; thermal dissipation is through the leads and the copper traces beneath them.