IWR1443BOOST: ADC resolution

kean zhao

Part Number: IWR1443BOOST
Other Parts Discussed in Thread: IWR1443

The following thread is a response from technical support to my question earlier.

IWR1443BOOST: ADC sampling amplitude - Sensors forum - Sensors - TI E2E support forums

In the following thread, RF ADC and general GP-ADC were mentioned, with a resolution of 16bit for RF ADC and 12bit for general GP-ADC as stated in the table in the data manual;

May I ask if the situation with IWR1443 is consistent with this? Also, I saw that the data in the IWR1443 data manual is 10bit.

AWR1843: AWR1843中ADC的分辨率 - 传感器论坛 - 传感器 - E2E 设计支持 (ti.com)

over 2 years ago

0 Pedrhom Nafisi over 2 years ago

TI__Mastermind 23347 points

Hello,

For IWR1443 it will be 12 bit for RF ADC and 10 bit for GP-ADC, just as the 1443 datasheet shows.

Best Regards,

Pedrhom

0 kean zhao over 2 years ago in reply to Pedrhom Nafisi

Prodigy 180 points

The data format for ADC output accuracy in the rl_sensor.h (mmwave_sdk_02_01_00_04) file is as follows. If IWR1443 ADC only supports 12bit accuracy, is it meaningless to configure 16bit and 14bit?

What is the impact of b8FullScaleReducFctr on data storage in the data format? Is it removing the low order digits in 16 bits? What is the actual ADC output data format if you choose 12 bit accuracy and 4 bit reduction?

typedef struct rlAdcBitFormat

{

/**

* @brief ADC out bits - 0(12 Bits), 1(14 Bits), 2(16 Bits)

rlUInt32_t b2AdcBits :2;

/**

* @brief Reserved for Future use

rlUInt32_t b6Reserved0 :6;

/**

* @brief Number of bits to reduce ADC full scale by

Valid range: 0 to (16 - Number of ADC bits)

For e.g. for 12 bit ADC output, this field can take values 0, 1, 2 or 3 \n

For 14 bit ADC output, this field can take values 0, 1 or 2 \n

For 16 bit ADC output, this field can take only value 0 \n

rlUInt32_t b8FullScaleReducFctr:8;

/**

* @brief ADC out format- 0(Real), 1(Complex), 2(Complex with Image band), 3(Pseudo Real)

rlUInt32_t b2AdcOutFmt :2;

/**

* @brief Reserved for Future use

rlUInt32_t b14Reserved1 :14;

}rlAdcBitFormat_t;

0 Pedrhom Nafisi over 2 years ago in reply to kean zhao

TI__Mastermind 23347 points

Hello,

So in many examples we have it set where " b2AdcBits :2". The ADC resolution itself is 12 bits, but padding it to 16 makes it better for data storing as it is a power of two.

Although b8FullScaleReducFctr is declared to 8, we never use this parameter and always set it to 0 since we are using 16 bit b2AdcBits. You can check the example code within SDK 02.01 to see how it is done.

Best Regards,

Pedrhom