25VT6A5VGEVB
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6
reset the controller. The first method is to toggle
Pin 8 (EN) of the Grayhill switch (SW2) to 0
(down position) and then back to 1 (up position).
The second method is to set VIN to 0 V and then
back up to the desired voltage, then turned on and
Vin re
−
established.
Shut down Procedure (VOUT 0.8 V
−
1.56 V):
1. Shut down the load.
2. Reduce the input voltage to zero and then shut
down the input power supply.
3. Reduce the driver voltage and controller voltage to
zero. Then shut down the driver power supply and
controller power supply.
Shut down Procedure (VOUT 1.56 V
−
1.8 V):
1. Shut down the load.
2. Adjust the potentiometer until the output voltage
measures 1.56 V.
3. Reduce the input voltage to zero and then shut
down the input power supply.
4. Reduce the driver voltage and controller voltage to
zero. Then shut down the driver power supply and
controller power supply.
Test Procedure
1. Before making any connections, make sure to set
all power supplies to 0 V, and make sure the load
current is 0 A.
2. Connect the oscilloscope probes at the desired test
points.
3. Connect the voltmeters/multi
−
meters to monitor
the required parameters. (Refer to Figure 4).
4. Set the output voltage to 1.2 V and the input
voltage to 12 V, following the Start
−
Up Procedure
specified in the previous section.
5. Obtain the required data and waveforms.
6. Follow the Shut
−
Down Procedure specified in the
previous section.
