Hi, look at www.jameco.com they sell 4 different chips from 20s to 240s, the one you need, 20 secs, rec and play is $5.95 ea, part number 107334 and the chip name is ISD1420P. I bought one several months ago and worked just fine with my 87C52. I also have the datasheet tell me if you need it. Regards, Germán.

P.S. I´ve copied and pasted the info:

Voice record/playback (20 sec.)
- Easy-to-use single-chip voice record solution
- Single voltage operation
- +5V (4.5V to 5.5V operating range
- Manual switch or microprocessor controllable
- Playbacl can be edge- or level activated
- Directly cascadable for longer durations
- Zero-power message storage - eliminates battery backup circuits
- Automatic power-down (push-button mode)
- P/N 141647: 3VDC @30mA
- 1 uA standby current (typical)
- Fully addressable to handle mulitple messages
- 100-year message retention (typical)
- 100K record cycles (typical)
- On-chip clock source
- On-chip automatic gain control (AGC)
- 28-pin DIP