STMicroelectronics FlexSPIN: SPI configurable stepper and DC multi motor driver evaluation board EVAL6460 EVAL6460 Data Sheet

   

   

   

80/139

 Doc ID 17713 Rev 1

L6460 integrates and makes accessible via SPI a general purpose multi-input channel 3.3V 
analog to digital converter (ADC).

The ADC can be configured to be used as:

●

8-bit resolution ADC.

●

9-bit resolution ADC.

The result of the conversion will always be a 9-bit word; the difference between the two 
configurations is that, to speed up the conversion, the resolution is reduced when the ADC 
is used in the 8-bit resolution mode.

The ADC is seen at software level as a 2 channel ADC with different programmable sample 
times; a finite state machine will sample the requests done through the SPI interface on both 
the channel and will execute them in sequence.

When used as 8-bit resolution the ADC can achieve a higher throughput and, if the minimum 
sample time is used, one conversion is completed in t = 5.5 µs. When used as 9-bit 
resolution ADC the circuit is slower and the minimum sample times are disabled. In that 
case the conversion will be completed in a time t= 10 µs.

The use of ADC type must be decided at the start-up by writing in the one time 
programmable ADC configuration register; no A/D conversion will be enabled if this register 
is not set from last power-up sequence.

This ADC can be used to measure some external pins as well as some L6460’s internal 
voltages. The converter is based on a cyclic architecture with an internal sample-and-hold 
circuit. Sample time can be changed using serial interface to enable good measure of higher 
impedance sources.