L6728H Datasheet, PDF (24/32 Pages) STMicroelectronics – Single phase PWM controller with Power Good

20 A demonstration board
L6728H
12.1 Board description
12.1.1
Power input (Vin)
This is the input voltage for the power conversion. The High-Side drain is connected to this
input. This voltage can range from 1.5 V to 12 V bus.
If the voltage is between 4.5 V and 12 V it can supply also the device (through the Vcc pin)
and in this case the R16 (0 Ω) resistor must be present.
12.1.2
Output (Vout)
The output voltage is fixed at 1.25 V but it can be changed by replacing the resistors R8
(sense partition lower resistor) and R13 (feedback partition lower resistor). R18 allows to
adjust OCP threshold.
12.1.3 Signal input (Vcc)
uct(s) _12.1.4
Obsolete ^{Product(s) - Obsolete Prod 12.1.5}
Using the input voltage Vin to supply the controller no power is required at this input.
However the controller can be supplied separately from the power stage through the Vcc
input (4.5-12 V) and, in this case, the R16 (0 Ω) resistor must be unsoldered.
Test points
Several test points are provided to have easy access at all important signal characterizing
the device:
– COMP: The output of the error amplifier;
– FB: The inverting input of the error amplifier;
– PGOOD: Signaling the regular functioning (active high);
– VGDHS: The bootstrap diode anode;
– PHASE: Phase node;
– LGATE: Low-side gate pin of the device;
– HGATE: High-side gate pin of the device.
Board characterization
Figure 14. 20 A demonstration board efficiency
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Doc ID 15725 Rev 1