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OSD3358-SM-RED
– User Guide
Rev. 1.0 9/19/2017
Octavo Systems LLC
Copyright 2017
Figure 45: OSD3358-SM-RED power rails
Figure 45 shows the main power rails of the PMIC connected to test points on the OSD3358-
SM-RED board schematic. This facilitates debug of the hardware system. The test points allow
probing of the power rails and verification of the boot up sequence. To give an initial indication
that the board is booting up, LED D1 is connected to SYS_VDD2_3P3V, since this power output
will come up as part of the boot sequence.
4.6
Clock inputs to the processor
OSD335x-SM has 2 clock inputs, OSC0 and OSC1.
4.6.1
OSC0:
This input is the main clock source for the processor and is the reference clock to all
subsystems except RTC. This clock input is a requirement for all designs with the OSD335x-
SM. For the OSD3358-SM-RED, this clock is 24MHz.
4.6.2
OSC1:
This input is the clock source for RTC system of the processor. The clock input for OSC1 should
be 32.768KHz generated by a single ended clock source or crystal oscillator. This clock input is
optional and can be removed if the RTC subsystem of the processor is not used.
