cheap (and maybe dirty) quadrature oscillator

[L. Daniel Rosa]

I've seen the "suspended bicore" and was and wondering if there's an easy way to make one with one output 90 degrees off the other. Comments?

[bobsRAC]

You need a clock, 3 inverters, and 2 d-latches.<p>` ` ` ` ` +----o<|---+
` ` ` ` ` | +-----+ `|
` ` ` ` ` +-|D ` Q|--+---Q0
` ` ` ` ` ` | ` ` |
clock-+-|>o-|> `` |
` ` ` |` ` `+-----+
` ` ` |
` ` ` |
` ` ` | ` +----o<|---+
` ` ` | ` | +-----+ `|
` ` ` | ` +-|D ` Q|--+---Q1
` ` ` | ` ` | ` ` |
` ` ` +-----|> `` |
` ` ` ` ` ` +-----+<p>Please excuse the ASCII art...<p>the --|>o-- is an inverter.<p>the `+-----+ is a d-latch.
` ` -|D ` Q|-
` ` `| ` ` |
` ` `|> `` |
` ` `+-----+<p>Note: if you copy/paste it to notepad, it looks just fine...<p>the circuit drives two d-latches with clocks 180deg out of phase. The d-latches are set up to divide by 2, and as the phase difference is a constant time difference, dividing the clocks by two means dividing the phase difference by two, making the phase difference 90deg.<p>BTW If you're wondering, the edit was a feeble attempt to fix the ASCII art... ohh well<p>[ January 28, 2003: Message edited by: bobsRAC ]</p>