S6E2C2 Datasheet, PDF (75/207 Pages) Cypress Semiconductor – 32-bit ARM® Cortex®-M4F FM4 Microcontroller

S6E2C2 Series
7. Handling Devices
Power-Supply Pins
In products with multiple VCC and VSS pins, respective pins at the same potential are interconnected within the device in order to
prevent malfunctions such as latch-up. All of these pins should be connected externally to the power supply or ground lines,
however, in order to reduce electromagnetic emission levels, to prevent abnormal operation of strobe signals caused by the rise in
the ground level, and to conform to the total output current rating.
Be sure to connect the current-supply source with the power pins and GND pins of this device at low impedance. It is also advisable
that a ceramic capacitor of approximately 0.1 µF be connected as a bypass capacitor between VCC and VSS near this device.
A malfunction may occur when the power-supply voltage fluctuates rapidly even though the fluctuation is within the guaranteed
operating range of the VCC power supply voltage. As a rule of voltage stabilization, suppress voltage fluctuation so that the
fluctuation in VCC ripple (peak-to-peak value) at the commercial frequency (50 Hz/60 Hz) does not exceed 10% of the standard
VCC value, and the transient fluctuation rate does not exceed 0.1V/μs at a momentary fluctuation such as switching the power
supply.
Crystal Oscillator Circuit
Noise near the X0/X1 and X0A/X1A pins may cause the device to malfunction. Design the printed circuit board so that X0/X1,
X0A/X1A pins, the crystal oscillator (or ceramic oscillator), and the bypass capacitor to ground are located as close to the device as
possible.
It is strongly recommended that the PC board artwork be designed such that the X0/X1 and X0A/X1A pins are surrounded by
ground plane, as this is expected to produce stable operation.
Evaluate the oscillation introduced by the use of the crystal oscillator by your mount board.
Sub Crystal Oscillator
The sub-oscillator circuit for devices in this family is low gain to keep current consumption low. To stabilize the oscillation, Cypress
recommends a crystal oscillator that meets the following conditions:
Surface mount type
Size: More than 3.2 mm × 1.5 mm
Load capacitance: approximately 6 pF to 7 pF
Lead type
Load capacitance: approximately 6 pF to 7 pF
Document Number: 002-05030 Rev.*A
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