Digital power controller matches analogue control bandwidth and transient response

March 20, 2014 // By Graham Prophet
Analog Devices’ ADP1055 is an advanced digital power controller with PMBus interface for high-density, isolated DC-to-DC power supply system applications; it uses Analog Devices’ high-resolution, high-speed A/D converter sensing technology combined with proprietary non-linear transfer functionality to achieve high-bandwidth performance and transient response equivalent to traditional analogue switching controllers.

The ADP1055 is a versatile digital controller with six PWM (pulse-width modulation) logic outputs that can be programmed using a graphic user interface via the PMBus interface. The device enables high-energy-efficiency topologies including full bridge with precision drive timing and control of secondary synchronous rectifiers. The controller’s GPIO (general-purpose I/O) can be configured for active clamp secondary energy efficient snubbing. Energy efficiency is further improved using adaptive dead-time compensation to improve the efficiency over the load range. Programmable light-load-mode operation combined with low device power consumption (<150 mW) reduces system low-power standby losses.

The chip provides accurate analogue and digital fault signalling via the PMBus and configurable GPIO. The device also records first instance of fault and provides ‘black box’ fault history recording capability—ideal for analysing system failure mechanisms and reliability.

The controller’s GUI (graphic user interface) enables you to design and store settings in the high-reliability, internal EEPROM memory. The digital power controller is available in a 5 x 5-mm LFCSP package—an optimal size for high-density, high-frequency, compact, isolated DC-to-DC power modules or embedded designs for networking, communications and industrial applications operating from 100W and higher.

The device costs $4.60 (1,000). An evaluation board features an isolated full bridge topology with full bridge secondary side rectification operating at 125 kHz switching frequency. Its rated output is 12V, 20A with an input ranging from 38-60VDC; it costs $300. A simpler daughter card allows you to retrofit the ADP1055 into existing design solutions - $100.

Analog Devices; www.analog.com/ADP1055