[sci.electronics] stereo A/D sigma delta converters

charlie@oakhill.UUCP (Charlie Thompson) (10/27/88)

I guess this question is a good one for Dr. Max Hauser.  I heard
a *rumor* that Crystal Semiconductor is going to announce a stereo
sigma delta A/D converter next week at the AES show in LA.  Max or
anybody know anything about this *rumor*?  Hello linear phase anti-
aliasing! 
 
- C.D.T.

bill@videovax.Tek.COM (William K. McFadden) (11/09/88)

In article <1619@radio.oakhill.UUCP> charlie@oakhill.UUCP (Charlie Thompson) writes:
>I guess this question is a good one for Dr. Max Hauser.  I heard
>a *rumor* that Crystal Semiconductor is going to announce a stereo
>sigma delta A/D converter next week at the AES show in LA.  Max or
>anybody know anything about this *rumor*?  Hello linear phase anti-
>aliasing! 

I just returned from AES.  From the Crystal CS5326 data sheet:

Features:

   o  Complete Stereo A/D System
         Delta-Sigma A/D Converters
         Digital Anti-Alias Filtering
         S/H Circuitry and Voltage Reference

   o  Adjustable System Sampling Rates
         32 KHz, 44.1 KHz, 48 KHz  [anti-alias filter automatically scales
                                    to sampling frequency]
   o  Low Noise and Distortion
         94 dB dynamic range
         0.0015% THD

   o  Internal 64X Oversampling

   o  Linear Phase Digital Anti-Alias Filtering
         0.001 dB Passband Ripple
         86 dB Stopband Rejection

   o  Low Power Dissipation: 500 mW
         Power-Down Mode for Portable Applications


General Description:

The CS5326 is a complete Analog-to-Digital converter for stereo digital audio
systems.  It performs sampling, analog-to-digital conversion and anti-aliasing
filtering, generating 16-bit values for both left and right inputs in serial
form.  The CS5326's output word rate can be up to 50 KHz per channel.

The CS5326 uses delta-sigma modulation to achieve high performance.
Oversampling, followed by digital filtering and decimation, greatly eases
external alti-alias filter requirements.  [I'll say, in the typical connection
diagram, the external anti-aliasing filter is a .01uF capacitor and a 51 ohm
resistor!]  The CS5326 oversamples at 64X the output word rate and uses a
3-stage digital FIR filter to achieve 94dB Signal-to-Noise Ratio and 0.0015%
THD over a 10 Hz to 22 KHz bandwidth.  The FIR filters offer linear phase,
0.001 dB passband ripple [!], and >86 dB stopband rejection.

The CS5326 is packaged in a 0.6" wide 28-pin plastic DIP.  Powered from +/- 5V
supplies, the CS5326 dissipates 500 mW, and includes a power-down mode for
battery powered applications.


Analog Characteristics  (Ta = 25 C, Full-Scale Input Sinewave, 1 KHz, 48 KHz
output word rate)

Resolution:  min 16 bits
Signal-to-(Noise + Distortion):  typ 92 dB, 10Hz to 22 KHz
THD:  max 0.003%  typ 0.0015%, Vin = +/- full-scale
      typ 0.001%, Vin = -20 dB
Dynamic Range:  min 93 dB, typ 94 dB
Interchannel Phase Deviation: typ 0.0001 degrees [!]
Interchannel Isolation at 20 KHz:  typ 105 dB
Interchannel Gain Mismatch:  typ 0.05 dB
Gain Error:  max +/- 5% [due to on-chip voltage reference, I'm told]
Gain Drift:  typ 150 ppm/degree C  [ditto]
Offset Error (after calibrtion):  +/- 15 LSB  [has on-chip offset calibration
                                               mode.  will also cal out offset
                                               of driving source]
Input Voltage Range:  +/- 3.6 V for full-scale output


[Differential Nonlinearity is essentially zero because of the one-bit sampler
in the front-end.  A plot in the data sheet shows it to be within 1/4 LSB over
the entire range of the converter.  The typical connection diagram shows
external components consist of 11 capicators (mostly for power supply
decoupling), 3 resistors, 1 inductor (decoupling), and a clock source.  That's
all that's needed for a complete stereo converter.]

-- 
Bill McFadden    Tektronix, Inc.  P.O. Box 500  MS 58-639  Beaverton, OR  97077
UUCP: bill@videovax.Tek.COM,  {hplabs,uw-beaver,decvax}!tektronix!videovax!bill
GTE: (503) 627-6920    Funniest new cartoon title: Teenage Mutant Ninja Turtles

smadi@rlgvax.UUCP (Smadi Paradise) (11/09/88)

Sounds great (no pun intended). Does anybody have prices (one off)?

On

bill@videovax.Tek.COM (William K. McFadden) (11/11/88)

In article <1026@rlgvax.UUCP> smadi@rlgvax.UUCP (On Paradise) writes:
>Sounds great (no pun intended). Does anybody have prices (one off)?

They said it would cost $48 in 1000s.  The unit price will most certainly be
a lot higher.  I know somebody is going to ask about availability, so I'll
just tell you.  Samples are supposed to be available by the end of first
quarter 89, will full production by mid-year.
-- 
Bill McFadden    Tektronix, Inc.  P.O. Box 500  MS 58-639  Beaverton, OR  97077
UUCP: bill@videovax.Tek.COM,  {hplabs,uw-beaver,decvax}!tektronix!videovax!bill
GTE: (503) 627-6920    Funniest new cartoon title: Teenage Mutant Ninja Turtles

todd@ivucsb.UUCP (Todd Day) (11/13/88)

In article <5303@videovax.Tek.COM> bill@videovax.Tek.COM (William K. McFadden) writes:
_I just returned from AES.  From the Crystal CS5326 data sheet:
_
_Features:
_
_   o  Complete Stereo A/D System
_         Delta-Sigma A/D Converters
_         Digital Anti-Alias Filtering
_         S/H Circuitry and Voltage Reference

Are they going to do a D/A also?

 
   /| Todd Day (805)968-9352 |\   "(sniff) (sniff) I think I smell a SNAPPER!"
+-+ | The Audio Club at UCSB | +-+
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bill@videovax.Tek.COM (William K. McFadden) (11/16/88)

In article <383@ivucsb.UUCP> todd@ivucsb.UUCP (Todd Day) writes:
>Are they going to do a D/A also?

Crystal does not list any D/A converters in its data book and did not have any
at the show.  I think they have left D/A to Burr-Brown and have gone after the
more lucrative A/D market (in my opinion, of course).
-- 
Bill McFadden    Tektronix, Inc.  P.O. Box 500  MS 58-639  Beaverton, OR  97077
UUCP: bill@videovax.Tek.COM,  {hplabs,uw-beaver,decvax}!tektronix!videovax!bill
GTE: (503) 627-6920    Funniest new cartoon title: Teenage Mutant Ninja Turtles