Single Power Supply Tracking Controller

The LTC2927 provides a simple solution to power supply tracking and sequencing requirements. By selecting a few resistors, the supply can be configured to ramp-up and ramp-down with differing ramp rates, voltage offsets, or time delays relative to other supplies or a master signal.

By forcing current into a feedback node of an independent supply, the LTC2927 causes the output to track a ramp signal without inserting any pass element losses. Because the current is controlled in an open-loop manner, the LTC2927 does not affect the transient response or stability of the supply. The compact solution at point of load minimizes the trace length of the DC/DC circuit sensitive FB node. Furthermore, it presents a high impedance when power-up is complete, effectively removing it from the DC/DC circuit.

Applications

* VCORE and VI/O Supply Tracking

* Microprocessor, DSP and FPGA Supplies

* Multiple Supply Systems

* Point-of-Load Supplies

* Flexible Power Supply Tracking

* Tracks Both Up and Down

* Power Supply Sequencing

* Supply Stability is Not Affected

* Low Pin Count

* Controls Single Supply without Series FETs

* Adjustable Ramp Rate

* Available in 8-Lead ThinSOT™ and 8-Lead (3mm × 2mm) DFN Packages