QS7779CM/QS7779PM
QSurround Matrix Surround Decoder/Virtualizer
Device Specifications - Preliminary Information
Overview:
The QS7779 is an audio processor IC which implements a decoder for a stereo matrix encoded source material such as
Dolby Surround, along with surround virtualization using QSurroundTM technology developed by QSound Labs, Inc.
This chip also produces an enhanced stereo sound field for a stereo input signal. If the input signal contains matrix
encoded surround sound, the chip automatically decodes it and produces virtualized surround sounds for two-speaker
playback.
Feature:
•
•
•
•
•
•
•
•
Dolby Surround decoder capability
Virtualized surround sound with two speakers
Stereo sound enhancement
Center channel output option
Two enhancement levels
Parallel and serial digital interface for mode control
QS7779CM for I2C 2 control pins serial interface (Data, Clock)
QS7779PM for 3 control pins serial interface (Data, Clock and Strobe)
DC 5 to 13 volt supply
24-pin SSOP packaging
Application:
• Audio systems including TV, AV amps, Mini System, DVD, VCD, SVCD and VCR
• Computer-based multimedia products, including sound cards and powered loud speakers
Pin Configuration:
Three-Wire Serial Interface
Ref: QS7779R12.DOC
Rev: 1.02
QS7779 Data Sheet -- Preliminary
QSound Labs, Inc.
I2C Serial Interface
Date: 03/02/01
Page 1 of 7
QS7779CM/QS7779PM
QSurround Matrix Surround Decoder/Virtualizer
Device Specifications - Preliminary Information
Packaging Dimension:
IC Block Diagram:
Ref: QS7779R12.DOC
Rev: 1.02
QS7779 Data Sheet -- Preliminary
QSound Labs, Inc.
Date: 03/02/01
Page 2 of 7
QS7779CM/QS7779PM
QSurround Matrix Surround Decoder/Virtualizer
Device Specifications - Preliminary Information
Pin Functions:
Number
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
Name
Parallel
Serial
QXAC3
QXAC2
QXAC1
RIN
LIN
COUT
CIN
VREFIN
VREFOUT
VREF
GND
SPRD
SCL
BYP
SDA
P/S
VDIG
MUTE
STRB
LOUT
ROUT
QXBC4
QXBC3
QXBC2
QXBC1
VANA
QXAC4
Ref: QS7779R12.DOC
Rev: 1.02
I/O
I
I
I
I
I
O
I
O
O
I
O
I
I
I
I/O
I
I
I
O
O
I
I
I
I
I
Description
Capacitor
Capacitor
Capacitor
Right channel signal input
Left channel signal input
Decoded center signal output
Center signal input for summing to the right and the left signal output
Internally generated reference voltage (VANA/2)
Buffered reference voltage (VANA/2)
Signal reference input
Ground
Enhancement control (H: spread maximum, L: spread minimum)
Serial data shift clock
Bypass control (H: Bypass On, L: Enhance process On)
Serial data input (also ACK data output for I2C of QS7779CM)
Interface mode control (H: parallel I/O, L: serial I/O)
Digital power supply
Output mute control (H: mute on, L: mute off)
Serial data strobe (Not applicable to I2C of QS7779CM)
Left signal output
Right signal output
Capacitor
Capacitor
Capacitor
Capacitor
Analog power supply
Capacitor
QS7779 Data Sheet -- Preliminary
QSound Labs, Inc.
Date: 03/02/01
Page 3 of 7
QS7779CM/QS7779PM
QSurround Matrix Surround Decoder/Virtualizer
Device Specifications - Preliminary Information
Electrical Specification:
Absolute Maximum Ratings
Parameter
Supply voltage range (analog)
Supply voltage range (digital)
Input voltage range (analog)
Input voltage range (digital)
Power dissipation
Storage temperature range
Soldering temperature
Soldering time
Symbol
VANA
VDIG
VIANA
VIDIG
PD
Tstg
TSLD
tSLD
Rating
-0.3 to 15, and VANA>VDIG-0.3
-0.3 to 7
-0.3 to VANA +0.3
-0.3 to VDIG +0.3
-40 to 125
255
10
Unit
V
V
V
V
mW
°C
°C
Sec
Symbol
VANA
VDIG
TOPR
Limits
5 to 13 and VANA≥VDIG
4.5 to 5.5
0 to 70
Unit
V
V
°C
Recommended Operating Condition
Parameter
Operating voltage (analog)
Operating voltage (digital)
Operating temperature range
Electrical Characteristics
Parameter
Input voltage
Internal Gain
Internal Gain bypass
Analog input impedance
Reference voltage out
HIGH level input voltage
LOW level input voltage
HIGH level input current
LOW level input current
SCL width HIGH
SCL width LOW
Set-up time, SDA to SCL
Hold time, SCL to SDA
Set-up time, SCL to STRB
STRB width HIGH
Hold time, SDA to SCL
Set-up time, SCL to SDA
Hold time, SCL to SDA
Set-up time, SDA to SCL
SCL width HIGH
SCL width LOW
SCL rise time
SCL fall time
Operating current (analog)
Operating current (digital)
Standby current (analog)
Standby current (digital)
Signal to Noise Ratio
Frequency Response
Total Harmonic Distortion
Ref: QS7779R12.DOC
Rev: 1.02
Symbol
VIN
AV
AB
ZAIN
VREFOUT
VIH
VIL
IIH
IIL
t1
t2
t3
t4
t5
t6
tHD;STA
tSU;STA
tHD;DAT
tSU;DAT
tHIGH
tLOW
tR
tF
IANA
IDIG
IANASAVE
IDIGSAVE
S/N
f
THD
Condition
VANA = 12VDC;f = 1kHz;no clipping
VANA = 12VDC;f = 1kHz;spread = max
VANA = 12VDC;f = 1kHz;Bypass
LIN, RIN
VIN= VANA
VIN=GND
VANA = 12VDC;f = 1kHz;unweighted
VANA = 12VDC;f = 1kHz;Bypass
VANA = 12VDC;f = 1kHz;VIN = 1 VRMS
QS7779 Data Sheet -- Preliminary
QSound Labs, Inc.
(VANA=9V,VDIG=5V TA=25°C unless otherwise noted)
Limits/min Limits/typ Limits/max
Unit
1.2
VRMS
+8.6
dB
-0.1
dB
20
kΩ
VANA/2
V
2.4
V
0.5
V
µA
µA
4.0
µS
4.7
µS
250
nS
5.0
µS
250
nS
5.0
µS
4.0
µS
4.0
µS
5.0
µS
250
nS
4.0
µS
4.7
µS
1000
nS
300
nS
10
mA
0.3
mA
0.1
mA
0.035
mA
96
dB
20
20k
Hz
0.025
%
Date: 03/02/01
Page 4 of 7
QS7779CM/QS7779PM
QSurround Matrix Surround Decoder/Virtualizer
Device Specifications - Preliminary Information
Serial Interface:
Serial interface with 3 control pins (for QS7779PM)
Serial interface with I2C (for QS7779CM)
I2C address is {AD7-AD0}
} = {10110110}
}
Operating Mode:
This chip can be set to desired operating mode by control pins for the parallel interface (P/S pin sets to 1) or control
bits for the serial interface (P/S pin sets to 0). The control pins or bits configurations are shown in the following table.
BYP
1
0
0
X
X
Control Pins/Bits
SPRD MUTE PSAVE
X
0
0
0
0
0
1
0
0
X
1
0
X
X
1
Description
Bypass mode.
Stereo enhanced and virtual surround mode with lower enhanced level
Stereo enhanced and virtual surround mode with higher enhanced level
Mute mode. No signal at output pins.
Power save mode. This function is available with serial interface only
NOTE-1) X: don’t care
NOTE-2) PSAVE is not available with the parallel interface.
Ref: QS7779R12.DOC
Rev: 1.02
QS7779 Data Sheet -- Preliminary
QSound Labs, Inc.
Date: 03/02/01
Page 5 of 7
QS7779CM/QS7779PM
QSurround Matrix Surround Decoder/Virtualizer
Device Specifications - Preliminary Information
Application (QS7779PM):
Ref: QS7779R12.DOC
Rev: 1.02
QS7779 Data Sheet -- Preliminary
QSound Labs, Inc.
Date: 03/02/01
Page 6 of 7
QS7779CM/QS7779PM
QSurround Matrix Surround Decoder/Virtualizer
Device Specifications - Preliminary Information
Application (QS7779CM):
Ref: QS7779R12.DOC
Rev: 1.02
QS7779 Data Sheet -- Preliminary
QSound Labs, Inc.
Date: 03/02/01
Page 7 of 7