Texas Instruments TPS7A4700 Evaluation Module TPS7A4700EVM-094 TPS7A4700EVM-094 Ficha De Dados
Códigos do produto
TPS7A4700EVM-094
Operation
2.3
Initial Setup and Equipment Interconnect
•
Select the desired V
OUT
by programming the output voltage according to the instructions listed above in
the Output Voltage Set Note in
•
Disable the EVM by adding a shorting jumper to J9 from EN (Pin 2) to OFF (Pin3).
•
Before connecting the input power supply to the EVM, verify that the output voltage is set to the
desired supply voltage (+3 V to +35 V range) and that it is current limited to 2 A. With the input power
supply turned off, connect the positive voltage lead (+) from the power supply to V
desired supply voltage (+3 V to +35 V range) and that it is current limited to 2 A. With the input power
supply turned off, connect the positive voltage lead (+) from the power supply to V
IN
(J1, Pin 1) of the
EVM. Next, connect the ground lead (-) from the power supply to GND (J2, Pin 1).
•
Connect a 0- to 1-A load between V
OUT
(J3, Pin 1) and GND (J4, Pin 1).
3
Operation
1. Turn on the input power supply and verify that the output voltage, V
OUT
, is near 0 V.
2. Enable the output by reconnecting the jumper on J9 to short the EN (Pin 2) to the ON (Pin 1).
3. Vary the load current and V
IN
voltage as necessary for test purposes.
NOTE:
Note: Power dissipation (P
DISP
) across the TPS7A47xx is dependent on the V
IN
to V
OUT
voltage drop and the output load current, I
Load
(P
DISP
= (V
IN
– V
OUT
) × I
Load
). If the power
dissipation is high, the output voltage may continuously transition on-off-on, due to the
shutdown effect of the thermal limit shutdown circuit.
shutdown effect of the thermal limit shutdown circuit.
4
Test Results
This section provides typical performance waveforms for the EVM, characteristic of this design.
4.1
Turn On Characteristic
shows the V
OUT
ramp-up waveform at turn-on (ENable) as well as the input surge current into the
IN pin of the LDO itself when the LDO starts-up into a fully loaded output.
Figure 1. Turn On Sequence
3
SLVU741A – May 2012 – Revised August 2013
TPS7A47xxEVM-094 Evaluation Module
Copyright © 2012–2013, Texas Instruments Incorporated