The LTC2921 and LTC2922 monitor up to five supplies and force them to track on power-up in multiple supply systems. Using external N-channel pass transistors, the supplies can be ramped up at an adjustable rate. Automatic remote sense switching allows the DC/DC converters to compensate for series voltage drops in the wiring. An incorrect level on one or more of the supplies triggers disconnect of all supplies. Tight 1% accuracy and glitch immunity on the low 0.5V monitoring level ensure no false error disconnects. The LTC2921 and LTC2922 each feature an adjustable electronic circuit breaker to protect the VCC supply against short circuits. Capacitance at the TIMER pin programs the delays in the monitoring sequence. The LTC2921 includes three remote sense switches in a 16-pin narrow SSOP package, while the LTC2922 includes five remote sense switches in a 20-pin TSSOP package. Both parts are available for VCC supply voltages of 5V, 3.3V, and 2.5V.
