STEVAL-ISA192V1 (STMICROELECTRONICS)

The STEVAL-ISA192V1 from STMicroelectronics is a 7W dual output flyback converter with standby managed by capacitive touch using VIPer0P and STM32L. This offline converter key feature is zero power mode (ZPM), an idle state during which the device is totally shut down. The IC enters ZPM by pulling OFF pin to SGND for more than 10ms and exits ZPM (resuming normal switching) by pulling ON pin to SGND for more than 20µs. To achieve extremely low input power consumption, the IC is biased through a diode coming from +7V which maintains VCC voltage high enough (> 4.5V) to prevent internal HV current source activation. The board is equipped with STM32L0 microcontroller which detects tactile push buttons and capacitive touch interface. The STM32L0 core manages VIPer0P to achieve minimum power consumption in ZPM while supplying microcontroller and user interface (capacitive touch, push button) and still maintaining overall efficiency quite high in standard operation mode.