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OSD3358-SM-RED
– User Guide
Rev. 1.0 9/19/2017
Octavo Systems LLC
Copyright 2017
4.2
Additional functions of the PMIC
The PMIC also performs some tertiary functions. A few of the key functions are listed below. For
a complete explanation of all the functions provided by the TPS65217C PMIC refer to the
datasheet (
http://www.ti.com/product/TPS65217/datasheet
).
1. The PMIC retrieves the processor from OFF or SLEEP mode upon detecting a falling
edge on PWR_BUT signal. It also power cycles the processor if PWR_BUT signal is
held low for more than 8 seconds by holding the power button S2 down.
2. It provides an active low wake up signal (PMIC_NWAKEUP) which is de-asserted when
a wakeup event is detected and is connected to EXT_WAKEUP pin of the processor.
3. The PMIC has an interrupt pin (PMIC _NINT) to signal an event or fault condition to the
processor via EXTINT pin. The pin is released when the processor reads the INT
register.
4. PMIC provides a linear charger for Single Cell Li-Ion batteries and allows charging of the
battery and powering of the system at the same time. More information on this feature
can be obtained from the datasheet.
5. The TPS65217C provides protection to AM335x and itself in the event of catastrophic
situations like an unexpected short or excessive current leakage. Please refer to the
OSD335x Power application note (
https://octavosystems.com/app_notes/osd335x-
) for information on how to design the power system for an
application with OSD335x.
4.3
Input power
Figure 39: OSD3358-SM-RED input power circuit
