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dc1923af
DEMO MANUAL DC1923A
Quick start proceDure
2. With power OFF connect the power supply (PS1) as
shown in Figure 3. If accurate current measurements
are desired (for efficiency calculations for example) then
connect an ammeter (AM1) in series with the supply
as shown. The ammeter is not required however.
3. Connect a 50mA load to VOUT as shown in Figure 3
(100Ω for VOUT = 5V). Connect an ammeter (AM2)
if accurate current measurement or monitoring is
desired.
4. Turn on PS1 and slowly increase voltage until the
voltage at VIN is 4V.
5. Verify VOUT is ~5V.
6. VIN can now be varied between 2.42V and 15V. VOUT
should remain in regulation.
7. Load current (IOUT) can also be varied. The maximum
IOUT is a function of VIN and the current limit. Consult
the data sheet for more information on IOUT vs VIN.
In general for VIN > VOUT IOUT can be increased to
200mA. For VIN < VOUT IOUT capability will be reduced.
8. For operation in fixed frequency (PWM) mode move
Jumper JP3 to FIXED FREQ. See the data sheet for
more information on Burst Mode operation.
9. NOTE: If VOUT drops out of regulation, check to be
sure that VIN is not below the minimum value for
regulation (see data sheet).
For USE with a Solar Cells/MPPC:
10. With power OFF move jumper MPPC (JP2) to ON.
11. If using a power supply as the source, place a mini-
mum of 10Ω, 10W resistor in series with the input to
simulate the source resistance. If using a solar cell(s)
or high impedance source, no additional resistance
should be needed.
12. Set resistor R6 to a value which will set the MPPC
pin to the desired voltage. See the data sheet section
Programming the MPPC Voltage for more information.
13. With no load and the MPPC voltage set, increase the
source voltage above the MPPC set point. VOUT should
be in regulation. As the load is increased VIN will drop
until it reaches the MPPC set voltage. As the load is
increased further, VOUT will drop out of regulation,
but VIN will be regulated to the set point voltage. This
is to prevent the input source from collapsing and to
allow the maximum power to be extracted from the
source.
14. Consult the data sheet for more information on maxi-
mum power point control (MPPC) operation.
For USE with a DUST Networks MOTE demo board:
15. Connector J1 is designed to interface with a Dust
Networks mote demo board. Consult the Dust
®
documentation for optimal VOUT regulation setting.
In general the Dust Networks mote will operate with
VOUT set to 3.3V. However, care should be taken to
not overvoltage the mote. Newer motes may require
a different VOUT. The DC1923A demo board can be
configured for different VOUT voltages by simply
changing jumpers JP4, JP5 and JP6. To configure the
board for 3.3V set the jumpers as follows:
JP4:
VS1
VCC
JP5:
VS2
GND
JP6:
VS3
GND
16. Once the output voltage has been set to the proper volt-
age and with the power supply OFF connect DC1923A
to the Dust Networks mote demo board using J1.
See Figures 5 and 6 for the proper connections and
orientation. Move jumper JP7 to VOUT.
17. Once the boards have been connected, turn on PS1
and increase the voltage to approximately 3V. VOUT
should now be in regulation. VIN can now be varied
over the operating range and VOUT should remain in
regulation.
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