The alternate TCXO design lacks a EN signal

Problem environment

Oscillators of the kind used in the TCXO footprint designated Y1 sometimes require a CMOS high signal to a pin labeled EN, typically the first notched pin number one.

Steps to reproduce

1. Refer to the schematic
2. Review the alternate design for Y1
3. Assume a oscillator part with EN/1

Expected result

The EN/1 pin receives power resembling the pin four input.

Actual result

The EN/1 pin is left floating, or possibly hacked to short with ground.

Note

This problem may cause the alternate oscillator design to be cancelled, if it becomes difficult to support or implement.

Workaround

Conduct messy wire hacking to bridge pin one with pin four of the oscillator circuit.

1. Cut the trace from Y1 to XTB/H7
2. Carefully bridge Y1 pin one to four

Severity level

This is low priority because the project benefits more by using a crystal or resondator, rather than an expensive oscillator.

The worldwide stock of the only oscillator suitable without major circuit changes has depleted due to pandemic supply chain weakness, so keeping this problem in focus is a losing battle. Instead of supporting a XTAL TCXO alternate choice, the design assumes a well calibrated high quality XTAL crystal in a 2,5mm x 2,0mm 2520 package.