Geneva, May 18, 2015 – The STNRG digital-controller family, new from STMicroelectronics, helps designers maximize the advantages of digital power conversion, including high efficiency under all load conditions, enhanced safety, rich diagnostics, and convenient network connectivity.
Rugged enough for high-end industrial applications as well as outdoor equipment such as solar-power converters, EV charging stations, and industrial switched-mode power supplies (SMPS), the STNRG ICs contain ST’s unique State Machine Event Driven (SMED) high-resolution pulse-width modulation (PWM) generator, in combination with an STM8-based supervisory core. The new devices integrate 32KB EEPROM, 6KB RAM, an ADC, op-amp, I2C port, and GPIOs.
Configuring the SMED requires no specialist software competencies, unlike the usual DSP or microcontroller-based approach. The SMED can be triggered from the internal timer or an external event such as peak current, over current, or zero crossing. This allows a peak-current detecting buck converter, with constant off time set by the timer, to operate without intervention by the core processor. A simple P-I (proportional-integral) loop executed in the core sets the peak-current value for output regulation.
The STNRG family comprises the STNRG288A with four SMED-controlled outputs, the STNRG328A with five SMEDs, and the STNRG388A with six SMEDs. Designers have the option to connect two SMED cells together to generate dual gate-drive signals with inserted dead time for half-bridge configurations. ST’s SMED is already proven as a high-performing solution for digital control in STLUX ICs for LED lighting.
All devices are in production now, priced from $2.20 for the STNRG388A in TSSOP38 package, for orders of 1000 pieces.
ST’s STNRG digital-controller family will be shown at the PCIM trade show (Booth 551/Hall 9) in Nuremberg, Germany, onMay 19-21 2015.
