MPZ2012S221A datasheet(44/56 Pages) STMICROELECTRONICS

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Application board

The application board (STEVAL-L6983IV1) schematic is shown in the figure below.

Figure 50. Schematic of the application board (unregulated isolated output)

The additional input filter (in the dotted box in Figure 50, on the bottom side of the board) limits the conducted

emission on the power supply. In case the filter is not necessary or should be bypassed for any test, two 0 Ω

resistors should be placed at Rf1 and Rf2.

The isolated output supplied by the board is unregulated. Nevertheless, a post-regulation circuit (see schematic in

Figure 51) is provided on the bottom side (components not mounted). The values and the components indicated

in the BOM below (Table 9 ) are assumed for a dual voltage 18 V / - 5 V.

Figure 51. Proposed circuitry for post-regulation (not mounted, bottom side) for dual voltage (18 V / - 5 V)

If a different dual isolated voltage is necessary (for example, 15 V / - 6 V), the replacement of two components is

enough to adapt the board: the Zener diode DZ2 (with a diode providing the most suitable Zener voltage) and the

resistor divider (one of the two resistors) R1-R2, in accordance with the equation:

VISO+=1.2V∙R1+R2R2+VDZ1

(48)

L6983I

Application board

DS14040 - Rev 1

page 44/56

MPZ2012S221A 数据表(PDF) 44 Page - STMicroelectronics