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L6712A L6712

3.2 DIGITAL TO ANALOG CONVERTER AND REFERENCE

The built-in digital to analog converter allows the adjustment of the output voltage from 0.900V to 3.300V

as shown in Figure 6. Different voltages can be reached simply changing the Remote Amplifier Gain that

acts as a resistor divider (See relevant section).

The internal reference is trimmed during production process to have an output voltage accuracy of ±0.9%

and a zero temperature coefficient around 70°C including also error amplifier offset compensation. It is

programmed through the voltage identification (VID) pins. These are inputs of an internal DAC that is re-

alized by means of a series of resistors providing a partition of the internal voltage reference. The VID code

drives a multiplexer that select a voltage on a precise point of the divider (see Figure 6). The DAC output

Internal pull-ups are provided (realized with a 5

µA current generator up to 3V typ.); in this way, to program

a logic "1" it is enough to leave the pin floating, while to program a logic "0" it is enough to short the pin to

SGND.

The device offers a bi-directional pin REF_IN/OUT: the internal reference used for the regulation is usually

available on this pin with 3mA of maximum current capability except when VID code 111 is programmed;

in this case the device accepts an external reference through the REF_IN/OUT pin and regulates on it.

When external reference is used, it must range from 0.800V up to 3.300V to assure proper functionality of

the device.

Figure 6 shows a block schematic of how the Reference for the regulation is managed when internal or

external reference is used.

The voltage identification (VID) pin configuration or the external reference provided also sets the power-

good thresholds (PGOOD) and the Over/Under voltage protection (OVP/UVP) thresholds.

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