Detailed description

The board features the following key sections, as shown in Figure 1.

1. HIL Analog connector
2. HIL Digital connector
3. Measurement terminals
4. Analog IO stage
5. Digital Output stage
6. UART stage
7. Nucleo-64™ Connectors

HIL Analog Connector

The HIL Analog connector is a 96 pin DIN 41612/IEC receptacle connector that is directly pluggable into the Analog I/O connector, found on all Typhoon HIL simulator devices, followed by three rows of measurement terminals. Table 1 shows how HIL analog outputs and analog inputs are connected to Nucleo-64™ sockets, for STM32F334 and STM32G474.

HIL Analog Outputs are scaled from +/-10 V to 0-3.3 V as shown in Figure 2. Reference voltage REF/2 is derived as one half of the voltage present on Nucleo-64™ connector CN10 pin 7 (VREF+). VREF+ can have various values depending on the inserted Nucleo-64™ board (1.8V, 2.5V, 3.25V, and 3.3V). In most cases VREF+ is 3.3V (Nucleo-64™ VDD) producing a REF/2 voltage equal to 1.65 V. The equation for scaling HIL AO output voltage to ADC input voltage is:

HIL AI1, AI2, and AI3 are connected by default (with 0R0 solder bridges SB11, SB12, and SB21) to Nucleo-64™ pins PA4, PA5, and PA6. Solder bridges SB9 and SB10 are not mounted by default.

To protect against overvoltage conditions, HIL Analog Outputs feature series 120 Ω series resistors that, together with protection diodes, form a 3.3 V clamping circuit.

HIL Digital Connector

The HIL Digital Connector is a 96 pin DIN 41612/IEC receptacle connector that is directly pluggable into the Digital I/O connector, found on all Typhoon HIL simulator devices, followed by three rows of measurement terminals. Table 2 shows how HIL digital outputs and digital inputs are connected to Nucleo-64™ sockets, for STM32F334 and STM32G474.

HIL Digital outputs DO1-DO8 are scaled from 5 V to 3.3 V (VDD) as shown in Figure 3. Level shifter is enabled by default (DO-EN jumper header in Open position). Inserting a jumper socket into the DO-EN jumper header will disable all outputs of the level shifter. Each level shifter output can be disconnected by removing the corresponding SB1-SB8 0R0 solder bridge. Solder bridge SB3 0R0 is not mounted by default.

DO9 is inverted into an Open-Drain and a logic high on DO9 will hold the Nucleo-64™ MCU in reset.

DO32 and DI32 (HIL DIO functioning as UART RX and TX) logic level is 3.3V.

Nucleo-64™ connectors

Pinouts for Nucleo-64™ sockets are shown in Table 3 and Table 4. Nucleo-144™ boards can also be used with limited IO count functionality.

"Nucleo-64^TM", "Nucleo-144^TM", "STM32", and "STM32 Nucleo" are registered trademarks of STMicroelectronics International NV or its affiliates in the USA (US Patent and Trademark Office) and/or other countries.