L9780 datasheet(23/56 Pages) STMICROELECTRONICS

23 / 56 page

DocID026356 Rev 3

23/56

L9780

Main functionalities

measurement is able to operate in free running or synchronized mode, according to SPI

selection (bit SNC); if free running mode is selected, the timing state machine is

continuously running, otherwise if synchronized mode is selected the measurement cycle

starts for each rising edge on SY pin; if multiple rising edges are detected on SY pin during

one measurement cycle, they will be ignored. For a more detailed description of the bits

involved see Section 6.3.

When the INRC amplifier is selected by the MUX, the scaling amplifier gain is automatically

set to 1, and the nominal transfer function from INRC pin to A/D output is:

count_INRC

floor Ginrc INRC

VCCA

-----------------

1024







and the nominal transfer function is:

INRC

count_INRC

1024

----------------------------------

Ginrc

---------------

VCCA



where:

Ginrc is the gain of the INRC amplifier;

count_INRC is the result of the A/D conversion of INRC pin voltage;

INRC is the INRC pin voltage level.

INRC voltage resolution depends on different contributions:

A/D error conversion (±2 counts);

scaling amplifier gain accuracy (±0.5%);

scaling amplifier offset (±300 μV);

INRC amplifier gain accuracy (±1%);

INRC amplifier output offset (±21 mV);

VCCA voltage precision.

When the RCT2 amplifier is selected by the MUX, the scaling amplifier gain is automatically

set to 1, and the nominal transfer function from RCT2 pin to A/D output is:

count_RCT2

floor Grtc2 RCT2

VCCA

-----------------

1024







and the nominal transfer function is:

RCT2

count_RCT2

1024

-----------------------------------

Grtc2

----------------

VCCA



where:

Grct2 is the gain of the RCT2 amplifier;

count_RCT2 is the result of the A/D conversion of RCT2 pin voltage;

RCT2 is the RCT2 pin voltage level.

L9780 Datasheet(PDF) 23 Page - STMicroelectronics

L9780 Datasheet(HTML) 23 Page - STMicroelectronics

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56

Datasheet Download

Link URL