All-pass with switched-capacitor filter LTC1562

Question

I want to have all pass filter to intruduce few us secound to ms delay for 5 kHz bandwidth. I though the easiest way is to use switched capacitor filter's but is there any way to use switched capacitor. FilterCAD created by LT was nice but it doesn't support all-pass filter. Is there any a solution IC for me? What about LTC1562 (despite my hope, LTspice simulatioons revealed it couldn't provide sufficient delay)?

PKarantzalis952 · Accepted Answer

Hi, use the LTC1067 to clock tune an Allpass delay. 
 The attached image shows a 10kHz LTC1067 Allpass providing 53us delay with 1MHz clock. 
 A 100kHz clock increases the delay to 530us and a 10kHz increases delay to 5.3ms. 
 Note: The Allpass delay is up to one half the Allpass frequency, for example 53us delay up to 5kHz for a 10kHz Allpass.

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All-pass with switched-capacitor filter LTC1562

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