Figure 7.
STEVAL-GLA001V1 evaluation board power supply primary side components
High Voltage
Mains voltage
test point
SW100
Auxiliary voltage test
point
F100
SIOV100
C109
D102
“Line” and “Neutral” test points are available to measure mains voltage.
An auxiliary power supply is generated to supply the AC switch gate control: it is not regulated (fluctuates from
~12 V to ~23 V), referenced with respect to "Line" potential and can supply up to 150 mA for gate control.
“VCC_AC” and “GND_AC” test points are available to measure the power supply voltage level.
2.5.2
Power supply: secondary side
The power supply secondary side is represented by all the low power output insulated from mains voltage.
The transformer output provides 5 V regulated voltage thanks to an LDO regulator. A 3.3 V regulated voltage is
generated from the 5 V voltage thanks to a second LDO regulator.
Figure 8.
STEVAL-GLA001V1 evaluation board power supply secondary side components
Up to 500 mA can be sunk from the secondary side in all, as the 5 V and 3.3 V voltages are in serial.
The J200 connector can supply another board or other external electronic functions. In this case, you must ensure
that the sum of all current on the secondary side does not exceed the output current capability.
“5VDC”, “3.3V OUT” and “GND” test points are available to measure these two low voltages.
2.5.3
VDD selector
Some of the signals (push button, mode switch and ZVS) connected to the STM32 32-bit ARM Cortex MCU or
other microcontroller input are referenced to VDD to protect the voltage input capability of any microcontroller.
UM2304
Hardware function description
UM2304
-
Rev 3
page 8/46
