UM0756

Using the front panel board

Doc ID 16031 Rev 1

17/28

measured along with the rotary encoder which is also attached at the key inputs of the

STLED316S device.

The system operates at 5 V, so the logic level of the water level signal should be within the

range of 3.5 V - 5 V for high and 0 V - 1.5 V for low logic.

To use the water level sensor, a 1 k

ICB003V1 board. Without this, the system will not detect the water sensor level signal.

4.3.2

Standby

The system demonstrates a smart power management control system to control the power

of other host systems in order to save the maximum amount of power during standby. The

block diagram of the control system is as shown in Figure 16.

Figure 16.

Standby mechanism using host system and front panel

The host system can be connected to the front panel using jumpers J1 and J3 (see Table 4

and 5).

Table 4.

Connection of jumper J1

Pin. no.

Input signal

Function

1

Normally open

Normally open

2Common

Common

3

Normally closed

Normally closed

Table 5.

Connection of jumper J3

Pin. no.

Input signal

Function

9

PD4_STBY_INTR

Interrupt from STEVAL-ICB003V1 to host controller

indicating that STBY key has been pressed

11

GND

Ground reference of STEVAL-ICB003V1