Single chip micro and RF

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I am in the early design phase of a project that will require a single chip solution RF transceiver and micro which will control a motor and various housekeeping duties. I see an ATMEGA128RF that Atmel has. Is that the only choice? Or did I miss one? The design must be low current of course.

I will be changing from a nRF24LE1. At least that is my intention at the moment.

Last Edited: Fri. Oct 16, 2015 - 02:19 PM
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TI has a few too IIRC.

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I have a call into TI. I did not see anything on their website but I figured they SHOULD have one. I thought there might be others out there but really have not found anything as of yet. Nice to see Atmel having one but the current draw is a tad high. Though I have little to compare it to so I should not complain too much!

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Wow. How did I miss that one? I blame the fact that I used paper and pencil with my slide rule in college.

Thanks! (BTW, seeing as how my real first name is Jay, I have always liked your jayjay1974...)

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jaydhall wrote:
Nice to see Atmel having one but the current draw is a tad high.
Receiver on, current consumption: mega128RFA1 = 12mA. Atmel recently released a transceiver with reduced receive current: AT86RF233 = about 6mA (active RPC mode) (if you're willing to have a 2 chip solution like REB233SMAD-EK).
The usual power source is a coin cell; a rechargeable coin cell may work for one or two work shifts. Alternates are series AAA cells or one LFP cell.

"Dare to be naïve." - Buckminster Fuller

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I am forced to have a single chip solution at the moment. This might open up if needed. I have found quite a few other chips but would like to use Atmel. My complaint for the current RX needs was a bit quick, as I have not found anything lower as of yet.

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Atmel radios have lowest power consumption on the market. If you'll find a chip that comes even close, please do tell me, I'm really interested.

NOTE: I no longer actively read this forum. Please ask your question on www.eevblog.com/forum if you want my answer.

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>Nice to see Atmel having one but the current draw is a tad high

                          CC2531  CC2530  CC2533  m128RFA1
RX Current (Lowest) (mA)   20.5     20.5    21.6  16.6/12.5*
Standby Current (uA)        0.4      1.0     0.4      0.02 

Sensitivity (Best) (dBm)  -97.0    -97.0   -97.0   -100.0
TX Power (dBm)              4.5      4.5     4.5      3.5   
Link Budget (dB)          101.5    101.5   101.5    103.5
(RXSens+TXpwr)

*The RFA1 draws 16.6mA in RX_ON if the CPU core is active and
12.5mA if the CPU core is in power down.

Sources:
- http://www.atmel.com/devices/atm...
- http://www.ti.com/product/cc2530

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> but the current draw is a tad high.

This is UHF. With 1 GHz and more on the chip, a certain current
consumption is (by today's technical knowledge) unavoidable.

The trick is to minimize the Rx on duration. Tx power consumption
usually isn't a big deal as Tx on durations are low anyway.

Jörg Wunsch

Please don't send me PMs, use email if you want to approach me personally.

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There is a device from Nordic, the NRF 9E5 that has an integrated 8051/2 CPU. Rx current is 12.5mA and power down is a couple of uA. Bad news is there is no way to protect the software you develop.Big mistake on Nordic's part.... makes it commercially useless.

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> There is a device from Nordic, the NRF 9E5 that has an integrated
> 8051/2 CPU. Rx current is 12.5mA

For a sub-GHz device, this is a large figure. It's about the same as
the ATmega128RFA1 achieves on 2.4 GHz.

Jörg Wunsch

Please don't send me PMs, use email if you want to approach me personally.

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Idle rx on can be as little as x milliseconds per second and still have reliable 1/x second response. That puts the big power use on the transmit side, for continuous strobing until the receiver wakes.

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I did notice that the Atmel solution was the lowest one I have seen so far. Thanks for all the help!