[FAQ] AM62L, AM64x Custom board hardware design – ADC0 design guidelines

Hi Board designers, 

Thank you for the query.

AM64x

1. Supported ADC resolution and channels

The processor family supports 1 × 12-bit ADC, up to 4 MSPS, and 8 multiplexed analog inputs. See the device-specific silicon errata (advisory i2287) for guidance on using SR2.0 processor on existing board or recommendations for a new custom board design. For more details, see the General Connectivity Peripherals section in the Peripherals chapter of the devicespecific TRM. Note that the processor family ADC inputs are not fail-safe. Do not apply external inputs before the processor supplies ramps.

2. Guidelines for using ADC peripheral

See the device-specific silicon errata (advisory i2287) for guidance on using SR2.0 processor on existing board or recommendations for a new custom board design.

 Note that the processor family ADC inputs are not fail-safe. Do not apply external inputs before the processor supplies ramps and are stable.

Refer pin Pin Connectivity Requirements section for connecting the ADC inputs when complete ADC is not used or any of the ADC inputs are not used 

3.ADC0 input range 

The ADC0 module supports the below ADC reference pins

ADC0_REFN -   ADC0 Negative Reference J16
ADC0_REFP  -  ADC0 Positive Reference J15

Additionally the ADC0 modules includes VDDA_ADC0 ADC0 analog supply

ADC12B Electrical Characteristics describes the allowed range ADC range VADC0_VREFP and VADC0_VREFN

4.ADC inputs used as GPI 

The ADC inputs are connected to the AM64x GPIO1 module when configured to operate as general-purpose inputs (GPI). The assignment of each ADC0 pin to the GPIO1 module is defined in the ADC0 Signal Description table found in the datasheet.

These inputs are able to perform the same input function as any other GPIO1 input. Please read the GPIO sections in the TRM to understand the capabilities of these inputs.

AM62L 

1. Supported ADC resolution and channels

1x 12-bit Analog-to-Digital Converter (ADC)
– 10 bits of effective resolution (ENOB ≅ 10)
– Up to 4MSPS
– 4x analog inputs (time-multiplexed)

2. Guidelines for using ADC peripheral

Note that the processor family ADC inputs are not fail-safe. Do not apply external inputs before the processor supplies ramps and are stable.

Refer pin Pin Connectivity Requirements section for connecting the ADC inputs when complete ADC is not used or any of the ADC inputs are not used

3.ADC0 input range 

VADC0_VREFP Positive Reference Voltage = VDDA_ADC0

VADC0_VREFN Negative Reference Voltage = VSS

The ADC0 module does not support separate VADC0_VREFP and VADC0_VREFN pins 

4.ADC inputs used as GPI 

Not supported 

Regards,

Sreenivasa

Hi Board designers, 

Additional information on AM64x input range 

(34) AM6422: External Analog Reference for ADC0 - Processors forum - Processors - TI E2E support forums

https://e2e.ti.com/support/processors-group/processors/f/processors-forum/1304300/faq-am6442-adc0_dig_test-0-7-when-a-digital-inputs-can-these-eight-be-considered-as-main-gpio-and-or-interrupt-inputs-at-1-8v-logic

Regards,

Sreenivasa