MAXIM Integrated Products, represented in Australia by Arrow Electronics , has released the MAX6876 EEPROM-programmable, quad-voltage power supply tracker/sequencer.
The MAX6876 monitors four voltages and ensures proper power-up and power-down conditions for systems requiring voltage tracking and/or sequencing. The device allows voltage thresholds, slew rates, overcurrent limits and timing parameters to be programmed through an I(2)C interface and stored in internal EEPROM.
It has programmable undervoltage and overvoltage thresholds in 10mV increments for each supply input. When all voltages are within their specifications, the device turns on an external n-channel MOSFET to track or sequence the voltages to the system. All the voltages can be tracked together, sequenced independently, or tracked and sequenced in various combinations.
During voltage tracking, the voltage at the gate of each MOSFET is increased to turn on the n-channel MOSFET. The voltage at the source of each MOSFET is measured to ensure that all voltages dynamically track to within 125mV of each other. If any supply fails to track within 250mV from the reference ramp, or if the voltage fails to power up within a specific time frame, a fault condition occurs and the power-up mode is terminated. The MAX6876 offers a fast shut-off mode to prevent power-down problems. The device incorporates independent charge pumps to ensure that each external n-channel MOSFET is fully enhanced during normal operation.
Additional features include an auto-retry (or latch-off) mode, an overcurrent-detect feature, power-good output indicators and a reset circuit. It also has a synchronisation feature that allows up to four devices to operate in a master/slave mode and thus track up to 16 voltages. The MAX6876 is available in a 6mm x 6mm, 36-pin TQFN and is fully specified from -40ºC to 85ºC.