gstopp at fibermux.com gstopp at fibermux.com
Thu Mar 20 19:35:02 CET 1997

     Although progress in this direction will undoubtably continue, I don't 
     think the technology is up to an acceptable level for total 
     replacement of disctete analog circuits for all synthesizer functions 
     at this time.
     You can hook up a single 555 timer chip in a certain way and call it a 
     VCO. It will in fact change its frequency in response to a change in 
     control voltage. It will not however oscillate with precise waveforms 
     from 0.01Hz to 125KHz, with musically accurate exponential tracking.
     The same with all other functions - an FPAD may be able to do them in 
     a simple way, but certainly not in the way that a synthesizer user 
     would be satisfied with - not yet, at least.
     But it is good news to see things like this starting to happen!
     - Gene
     gstopp at fibermux.com

______________________________ Reply Separator _________________________________
Subject: FPAD from ZETEX
Author:  Mikko Helin <MHELIN at tne01.tele.nokia.fi> at ccrelayout
Date:    3/20/97 9:57 AM

       I think this information would be of some interest: ZETEX from UK 
       have developed a field programmable analog device. It can be
       used to build VCOs, filters, multipliers etc. One could actually 
       build a whole analog synth with these little devices by designing 
       it with Windows software an programming chips thru PC's parallel 
       printer port like any EEPROMS.
       The next text is from datasheets of TRACK020, which is the only device 
       they currently have. Look at www.zetex.com for more information.
       Issue 2 - December 1996 Provisional TRAC020
       The TRAC020 is the first universal Field 
       Programmable Analog Device (FPAD) . This 
       device provides a macro based solution to 
       analog design problems. The device contains 
       20 interconnected cells each of which can be 
       digitally programmed to one of eight 
       pre-defined functions.
       Configuration is readily achieved by the 
       integration of the TRAC software, hardware
       and the device itself. The software enables the 
       user to design and simulate the analog 
       application and then send the data to the TRAC 
       hardware to programme the device. The
       hardware is designed to facilitate the electrical 
       evaluation of the design.
       Many analog applications including:- 
       · Filters
       · Multipliers
       · VCOs
       · PLLs
       · Precision Voltage References
       · Automatic Gain Control
       · Frequency to Volts Conversion
       · User programmable
       · From design to silicon within the hour
       · A low risk and fast route from concept to 
       · For maximum flexibility each cell I/O can 
       be connected externally
       · The function of each cell can be digitally 
       programmed for LOG, ALOG, AUX, NON
       RECTIFY and OFF
       · The device can be programmed with a 
       standard eeprom for non-microprocessor 
       applications or for microprocessor
       applications via the data bus
       · Device is offered in two package styles : 
       - Small 36 pin SSOP package
       - production build 40 pin PDIP package 
       - prototype build
       · The TRAC software and hardware fully integrates design, simulation and 
       programming functions
       · For complex circuits the chips can be cascaded 
       · The device is fully reconfigurable

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