STMicroelectronics FlexSPIN: SPI configurable stepper and DC multi motor driver evaluation board EVAL6460 EVAL6460 Ficha De Dados

Doc ID 17713 Rev 1

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L6460 includes a multiple range 6-bit current sink DAC. The LSB value of this DAC can be 
selected using the DacRange[1:0] bits in the CurrDacCtrl register.

The output of this circuit is connected to GPIO[8] that is a 5 V tolerant pin. The value of this 
pin can be converted using ADC. The pin value can be scaled before being converted by 
enabling the internal resistor divider connected to this pin. If the current sunk by resistor 
divider is not acceptable the pin voltage can be converted without scaling its value. When 
the conversion without scaling resistor is chosen a clamping connection is used to avoid 
voltage compatibility of the pin to the ADC system. The clamping circuit will sink a typical 
current of half microampere from the pin during the sampling time.

The circuit is enabled by setting to logic ‘1’ the EnDac bit in the CurrDacCtrl register then the 
desired sunk current value is chosen by changing the value of the DacValue[5:0] bits in the 
same register being DacValue[0] the least significant bit and DacValue[5] the most 
significant bit.

 

Current Sink  

DAC 

DacValue[5:0] 

EnDac 

A2DChannel1 [4

:

0] 

A2DChannel2 [4

:

0] 

Combinatorial 

Mask 

Combinatorial 

Mask 

Address 

Recognized

 

Address 

Recognized

 

EnDac 

Clamp circuit  

Gpio8 Clamp 

(to ADC) 

EnDacScale

 

DacRange[1:0] 

Reference Current 

Generator 

Va3 

Gpio[8] 

DacRange [1:0]

 

Gpio[8] Digital Driver  

RCurrDac