Datasheet

AD converter L6460
80/139 Doc ID 17713 Rev 1
15 AD converter
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.