From: malcolm@apple.com
Date: Wed, 08 Dec 93 09:25:01 -0800
Subject: Hearing Chips at CCRMA
Message-Id: <9312081001.AA02660@apple.com>

Just a reminder..... John Lazzaro will present his hearing chips at tomorrow's
CCRMA Hearing Seminar.  I've attached more details to the end of my note.
Just what kind of cochlear modeling can you do in Silicon?  How do you attach
the chips to real systems?  

Please send me your ideas for next year.  I'm starting to put the new schedule
together.

-- Malcolm

------- Forwarded Message

The next CCRMA Hearing Seminar will feature John Lazzaro and his singing,
dancing, and HEARING chips!!!  John has been working at Caltech (with Carver
Mead's group) and at Berkeley on architectures and algorithms for silicon
models of hearing.

Several labs around the world have been building cochlear models in silicon.
But what do you do with all this data?  How do you get it into a computer
where the information can be used for more processing?  What kinds of 
processing can you do in silicon to make the assimilation of all this 
information easier?  John will be talkin about his models and chips next
Thursday at CCRMA.

	Who:	John Lazzaro (UC Berkeley)
	What:	Silicon Systems for Auditory Modeling.
	When:	Thursday December 9th at 11AM
	Where:	CCRMA Library (Top Floor of the Knoll at Stanford)

Come to CCRMA to see and hear more.  This is the last seminar for the year.
Let me know if you have suggestions or ideas for next year.

---- Malcolm


From: John Lazzaro <lazzaro@CS.Berkeley.EDU>

          Systems Technologies for Silicon Auditory Models

		     John Lazzaro -- UC Berkeley

	 (in collaboration with John Wawrzynek and Alan Kramer) 

       Recent VLSI research involves silicon implementations of
biological models of audition, using an analog design methodology.
These efforts have produced working prototypes of many early
representations of audition, including cochlear models, models of
spectral shape, pitch representations, and binaural representations
[1]. These circuits use weak-inversion design techniques to achieve
very low power dissipation.  For example, a recent silicon cochlea
design, that computes 51 cochlear filter outputs in real time,
dissipates 11 microwatts of power for the computation [2].

	Integrating these analog elements into a digital computing
system requires a careful approach. The interface methods must
complement and preserve the low power consumption, compact circuits,
and clean representations of analog auditory models. Our research
centers on developing appropriate circuit, architecture, and software
integration technologies for these models.

        In my talk, I will describe an integrated circuit that
combines a 120-channel model of spectral shape [3] with novel
technologies for non-volatile parameter storage and for communications
with digital systems [4].  While auditory input to the chip is an
analog waveform, all control input and data output of the chip are
digital. In this sense, our fabricated and functional chip can be seen
as a special-purpose, low-power analog-to-digital converter for
auditory applications. In addition to describing this integrated
circuit, I will also discuss software technologies we have developed
for using this chip in engineering applications. 

[1] Lazzaro, J. P. (1991). Biologically-based auditory signal processing
in analog VLSI. IEEE Asilomar Conference on Signals, Systems, and
Computers. (review paper)

[2] L. Watts, D. A. Kerns, R. F. Lyon, C. A. Mead (1992), Improved
Implementation of the Silicon Cochlea, IEEE Journal Solid State
Circuits, 27: 5, 692-700.

[3] Lazzaro, J. P. (1991). A silicon model of an auditory neural
representation of spectral shape.  IEEE Journal Solid State Circuits,
26: 772--777.

[4] Lazzaro, J. P., Wawrzynek, J., Mahowald., M., Sivilotti, M., 
Gillespie, D. (1993).  Silicon auditory processors as computer
peripherals.  IEEE Journal of Neural Networks 4:3 523--528.

------- End of Forwarded Message