ANT Forum

Hello,

I'm working on a small reference board containing an nRF24AP2 and have limited microprocessor IO pins available. Will be using async serial comms. If all I need is basic ON/OFF control of the ANT+ chip, are there any pitfalls associated with using a switched power rail and tying these 3 signal lines high/low as shown below?

VCC = switched power rail under uP control
TXD, RXD, RTS connected to uP
/RST = HIGH
/SUSPEND = HIGH
SLEEP = LOW

Don't see anything in the datasheet that indicates this wouldn't work, but figured it was worth asking here.

Thanks,
Brett      

That should work, but it might not be the most efficient in terms of latency and power consumption.

Have you considered making use of ANT low power states?

You can find more details on the different ANT power modes on AN13 Power States
http://www.thisisant.com/pages/developer-zone/ant-application-notes

Using the SLEEP line appropriately, instead of switching VCC, would let you reopen channels without having to go through the entire configuration, while drawing 2uA while in Idle mode. Using the SLEEP line would also let you go into SLEEP mode while not using the serial port. Depending on your requirements, it might be a better option.      

Thanks for the reply, alejandra!

I know using SLEEP is the preferred method to control power usage - will see if we can free up a dedicated IO from the microprocessor.

Best regards,
Brett