Texas Instruments TPL5111EVM, Руководство пользователя

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Operation
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3 Operation
Once the EVM is powered ON, the TPL5111 starts running. Refer to the datasheet of the TPL5111 for
further details on the timing. The TPL5111 has 2 modes of operation: TIMER mode and ONE SHOT
mode.
3.1 Timer Mode
In TIMER mode, the TPL5111 generates a periodic pulse at the DRVn pin. When a DRVn signal is
asserted by the TPL5111, the output of the TPS61029 is enabled, and the GREEN LED (D1) is turned on.
If the DONE switch is pushed, a DONE pulse is sent to the TPL5111, which de-asserts the DRVn pulse,
disabling the TPS61029, and turning off the GREEN LED. If the DONE switch is not pushed, the DRVn
pulse length is equal to the programmed value set by REXT_1 and REXT_2, minus 50 ms. When the
M_DRV switch is pushed, VDD is connected to the DELAY/M_DRV pin, simulating a manual power on
signal to the TPL5111. The length of the DRVn pulse in this case is equal to the amount of time the
M_DRV switch is pressed, plus the programmed time interval.
The DRVn pulse may be observed by attaching an oscilloscope probe to the DRV_N pin, as indicated in
Figure 3 .
Figure 3. Signal Monitoring Points
6 TPL5111EVM User 's Guide SNAU183 – July 2015
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