AFE3010: Latching Relay With LED

Hello Narendra,

When you say remain in ON state, I assume you mean LED remains on continuously?

You could either logically connect the states of RELAY (basically your load switch) to the digital state of SWOPEN. So if RELAY is latched open, then SWOPEN pin is held low, at which point Figure 13 will occur. This will fire SCR  and reset fault counter. As long as SWOPEN is held low, ALARM will remain on continuously. Once Relay is latched closes, SWOPEN goes high and system is ready to detect faults because fault counter was reset.

The other option is to use a another LED that is not controlled by ALARM, but is mechanically tied to relay state.

You can refer to figures 11, 13, and 14 on how to reset the device (reset fault error counter). Note it is possible to reset the device without having to fire SCR, but it requires a controlled low pulse on at SWOPEN (55ms, see td4 specification in section 6.5), but this practically requires another host MCU to create this signal.

Depending upon how you reset the device, this will dictate the type of relay. If SCR is going to fire again upon pressing PTT or SWOPEN, then you don’t want a load relay that is going to close from this.

Sincerely,

Peter