CC1125: Is there a way to generate full depth OOK at maximum RF output power?

Lauren Mayfield

Part Number: CC1125

Hi team,

Question from a customer-

The CC11xx users guide (SWRU295E) makes the statement “OOK modulation simply turns the PA on or off to modulate ones and zeros respectively” (Sec 5.2.2). This suggests that we should be able to generate OOK by turning the PA on and off. However….

Later, in the configuration register descriptions (PA_CFG0 – Power Amplifier Configuration Reg. 0) it makes the statement “For OOK with maximum depth the PA_POWER_RAMP-4.ASK_DEPTH must always be all zero hence for ASK/OOK with maximum depth the maximum ASK/OOK output power is 12.5dBm”

We would like to be able to generate full depth OOK (PA ‘on’ = 1 / PA ‘off’ = 0) at maximum RF output power. The first statement suggests that the hardware can do this. However the second statement suggests that this is not possible. Is there a way to generate full depth OOK at maximum RF output power? If it helps, we do not need to do pulse shaping for this application.

Thanks!
Lauren

over 4 years ago

0 RGW over 4 years ago

TI__Mastermind 30890 points

Hi,

Which market are you targeting for your regulatory tests (ETSI / FCC) ?

Regards,

Richard

0 Lauren Mayfield over 4 years ago in reply to RGW

TI__Expert 7180 points

This particular application will not be subject to FCC or ETSI regulatory test. We just need to be able to generate maximum depth OOK at maximum output power. No need to worry about the regulatory ramifications.

0 Lauren Mayfield over 3 years ago in reply to Lauren Mayfield

TI__Expert 7180 points

Is there an update on this?

Thanks,
lauren

0 RGW over 3 years ago in reply to Lauren Mayfield

TI__Mastermind 30890 points

If you are not subject to regulation requirements then just send at maximum output power.

//Richard

0 Lauren Mayfield over 3 years ago in reply to RGW

TI__Expert 7180 points

Richard-

We would like to do just that, however we do not know how to configure the part to generate OOK with 100% modulation at maximum output power. If it’s possible to do this, can you help us figure out how to do so? The datasheet seems to indicate that maximum output power for full-depth OOK is 12.5dBm. The thing that has us wondering is the comment that OOK is generated by turning the PA on and off – This suggests that we should be able to generate full-depth OOK at +15 or +16dBm.

0 RGW over 3 years ago in reply to Lauren Mayfield

TI__Mastermind 30890 points

Hi,

It is possible to send a maximum output power with OOK especially when you are not subject to regulatory requirements.

The output power was limited previously just to limit the TX bandwidth to comply to a regulatory standard.

Closing this thread to avoid duplicate emails.

Regards,

Richard

Sub-1 GHz

Sub-1 GHz forum

CC1125: Is there a way to generate full depth OOK at maximum RF output power?