SANYO LC78845Q

Ordering number : EN*5236
CMOS LSI
LC78845Q
Sample Rate Converter for Digital Audio
Preliminary
Overview
Package Dimensions
The LC78845Q is a synchronous sample rate converter for
digital audio signals.
unit: mm
3156-QFP48E
Features
[LC78845Q]
• Converts data sampled at 32 or 48 kHz to 44.1-kHz
sampled data.
• Passes 44.1-kHz sampled data trough without change.
• Supports 384fs and 512fs system clock rates.
• 8× oversampling filters
• Soft muting function
• Built-in PLL circuit
SANYO: QIP48E
Specifications
Absolute Maximum Ratings at Ta = 25°C
Parameter
Symbol
Maximum supply voltage
Conditions
Ratings
VDD max
I/O voltages
VI, VO
Unit
–0.3 to +7.0
V
–0.3 to VDD + 0.3
V
Operating temperature
Topr
–30 to +70
°C
Storage temperature
Tstg
–55 to +125
°C
DC Characteristics
Parameter
Symbol
Conditions
Input voltage range
VIN
Input high-level voltage
VIH
Input low-level voltage
VIL
Output high-level voltage
VOH
IOH = –1 µA
Output low-level voltage
VOL
IOL = 1 µA
Ta = –30 to +70°C
min
typ
0
max
VDD
0.7 VDD
Unit
V
V
0.3 VDD
VDD – 0.05
V
V
VSS + 0.05
V
This LSI can easily use CCB that is SANYO’s original bus format.
• CCB is a trademark of SANYO ELECTRIC CO., LTD.
• CCB is SANYO’s original bus format and all the bus
addresses are controlled by SANYO.
SANYO Electric Co.,Ltd. Semiconductor Bussiness Headquarters
TOKYO OFFICE Tokyo Bldg., 1-10, 1 Chome, Ueno, Taito-ku, TOKYO, 110-0005 JAPAN
22896HA (OT) No. 5236-1/10
LC78845Q
AC Characteristics
1. Audio data input
Parameter
Symbol
Conditions
min
typ
max
Unit
BCLKI pulse width
tBKW
50
ns
DATAI setup time
tDS
20
ns
DATAI hold time
tDH
20
ns
LRCKI hold time
tLH
25
ns
LRCKI setup time
tLS
25
ns
2. Audio data output
Parameter
Symbol
BCLKO pulse width
tBWO
DATAO output delay time
tDAD
Conditions
min
typ
max
Unit
25
ns
100
ns
DATAO setup time
tDSO
50
DATAO hold time
tDHO
50
LRCKO output delay time
tLRD
LRCKO setup time
tLSO
50
ns
LRCKO hold time
tLHO
50
ns
WCLKO setup time
tWSO
50
ns
WCLKO hold time
tWHO
50
ns
ns
ns
25
ns
No. 5236-2/10
LC78845Q
3. Serial input (CCB = low)
Parameter
CL pulse width
Symbol
Conditions
min
typ
max
Unit
tCLW
50
ns
DI setup time
tDS
20
ns
DI hold time
tDH
20
ns
CE pulse width
tCEW
50
ns
CE setup time
tCS
20
ns
CE hold time
tCH
20
DO0 to DO7 output delay time
ns
tDOD
25
ns
max
Unit
4. Serial input (CCB = high)
Parameter
CL pulse width
Symbol
Conditions
min
typ
tCLW
50
ns
DI setup time
tDS
20
ns
DI hold time
tDH
20
ns
CE setup time
tCS
20
ns
CE hold time
tCH
20
ns
DO0 to DO7 output delay time
with respect to the rise of CE
tDOD
25
ns
No. 5236-3/10
LC78845Q
Pin Assignment
Although the DVDD and AVDD pins in this IC are given different names to correspond to the internal circuit structure,
they are connected internally through the circuit substrate. As a result, if different voltages are applied to these pins,
abnormal currents will flow in the chip. Since this can cause latchup, power supplies with identical voltages and identical
power-on timings must be used.
Pin Functions
Pin No.
Symbol
Overview
Function
1
MKSEL
DF master clock selection
Low: 384fs, high: 512fs
2
INITB
Reset input
Low: initialization operation
3
MCK1
DF master clock input
4
BCLKI
Audio signal input
5
DGND
Digital system ground
6
DGND
Digital system ground
7
DVDD
Digital system power supply
8
LRCKI
9
DATAI
10
CCB
11
SPSEL
Audio signal bit clock input pin
Audio signal input
Audio signal left/right clock and data input pins
Serial input format specification
Selects the input format for data from the microprocessor input pins.
Serial/parallel control
Allows certain of the setting pins to be set from serial data over the
microprocessor interface.
Low: serial, high: parallel (states set by input pins)
Continued on next page.
No. 5236-4/10
LC78845Q
Continued from preceding page.
Pin No.
Symbol
12
CE
13
CL
14
DI
15
DO7
16
DO6
17
DO5
18
DGND
Digital system ground
19
DVDD
Digital system power supply
20
DO4
21
DO3
22
DO2
23
DO1
24
DO0
25
DATAO
26
LRCKO
27
WCLKO
28
BCLKO
29
DGND
Overview
Function
Data enable signal input
Microprocessor input pins
Shift clock input
Address/data input
Output of 8-bit parallel data according to microprocessor input
Parallel data output
Parallel data output
Output of 8-bit parallel data according to microprocessor input
Audio signal output
Audio signal outputs (data, left/right clock, word clock, and bit clock)
Digital system ground
30
N.C
31
AGND
32
VCO
PLL control
Low-pass filter connection
33
VIN
PLL control
Free-running setting
34
R
PLL control
VCO band adjustment
35
STOP
Oscillator stop signal input
Low: oscillator stopped, high: PLL running
36
UNLK
Unlock detection output
Outputs a high level when the PLL circuit is unlocked.
37
MCK2
Synchronization clock output
Outputs the clock generated by the VCO.
38
AVDD
Analog system power supply
39
AVDD
Analog system power supply
40
MUTE
Muting
Low: muting off, high: muting on
41
FSEL3
Output data fs selection
Low: fs data, high: 2fs data
42
TEST1
Test pin
Must be held low during normal operation.
43
DVDD
Digital system power supply
44
DVDD
Digital system power supply
45
FSEL2
46
FSEL1
47
TEST2
48
TEST3
—
Analog system ground
Input signal fs selection
Selects the fs for the input signal.
Test pins
Must be held low during normal operation.
No. 5236-5/10
LC78845Q
Block Diagram
Note: 1.
2.
3.
4.
5.
BCLKI, LRCKI, DATAI
BCLKO, LRCKO, DATAO, WCLKO
R, VIN, VCO, UNLK
MKSEL, FSEL1, FSEL2, MUTE, STOP
CCB, SPSEL, CE, CL, DI
No. 5236-6/10
LC78845Q
Input and Output Formats
1. Input format
Audio data is input through the audio data input pins (BCLKI, LRCKI, and DATAI) in the following format.
MKSEL = L: fBCK = 48fs
MKSEL = H: fBCK = 64fs
2. Output format 1
Audio data is output through the audio data output pins (BCLKO, WCLKO, LRCKO, and DATAO) in the following
format.
BCLKO = 64fs (fixed)
LRCKO = fs (fixed)
WCLKO = 2fs (fixed)
3. Output format 2 (When the input fs is 44.1 kHz)
When data sampled at 44.1 kHz is input, that data is output directly without change. The WCLKO output is held low
in this case.
No. 5236-7/10
LC78845Q
Pin Settings
1. Input master clock setup (when SPSEL is high)
Input the master clock for the internal digital filters to MCK1 (pin 3). Also, set whether that clock is 384fs or 512fs
with MKSEL (pin 1).
Pin
L
H
MKSEL
384fs
512fs
2. Input data fs setting (when SPSEL is high)
The input data sampling frequency must be set. FSEL1 and FSEL2 (pins 46 and 45) are used for this setting. Data
sampled at a 32 or 48 kHz sampling frequency is converted to data with a 44.1 kHz sampling frequency. If data
sampled at 44.1 kHz is input, it is passed through unchanged.
Sampling frequency
FSEL1
FSEL2
44.1 kHz
0
✕
48 kHz
1
0
32 kHz
1
1
3. Output data setup
The output data can be switched between fs and 2fs. FSEL3 (pin 41) is used to change this setting.
Pin
L
H
FSEL3
fs
2fs
4. Setup from serial input
The MKSEL, FSEL1, FSEL2, MUTE, and STOP settings can be set using the serial bus by setting SPSEL (pin 11)
low. The 8 bits of input data is output in parallel regardless of the SPSEL setting.
Serial input format 1 (CCB = high)
Serial input format 2 (CCB = low)
No. 5236-8/10
LC78845Q
Data
INITB = H
SPSEL = L
INITB = L
B0 to B3
A0 to A3
LSI selection
Address
—
—
D0
D1
D2
D3
D4
D5 to D7
MKSEL
FSEL1
FSEL2
MUTE
STOP
—
L
L
L
H
L
H
The data and the signals correspond as listed in the tables. Since the external pins (MKSEL etc.) set by the serial
input are unused, applications must assure that these pins do not become floating. If initialization is performed, set
the initial values listed in the table.
5. Muting
A soft muting function is applied to the data if the MUTE pin (pin 40) is set high when data with a 32 or 48 kHz
sampling frequency is input. The input signal values are gradually attenuated so that the data reaches –∞ 1024/fs
(seconds) later. When the soft muting function is turned off, the amplitude becomes the same as that of the input
1024/fs (seconds) later.
For input data with a 44.1 sampling frequency, the data is forcibly set to 0 on the next rising edge of the LRCK
signal after the MUTE signal goes from low to high. Similarly, data is output on the next rising edge of the LRCK
signal after the MUTE signal goes from high to low.
6. Initialization
When power is first applied, the LSI must be initialized when the pin settings are changed. Initialization is performed
by holding INITB (pin 2) low for at least 1 µs in the state where the MCK1 signal is input after the power supply
voltage has stabilized.
No. 5236-9/10
LC78845Q
7. PLL block
The PLL block generates a 14.112 MHz master clock (MCK2) that is used for all three frequencies; 32, 44.1, and
48 kHz, when either 32 or 48 kHz is specified as the input data sampling frequency.
• STOP pin setting
STOP
Function
L
The VCO is stopped.
H
The VCO operates.
• UNLK pin
UNLK
Function
L
Indicates that the PLL circuit is locked.
H
Indicates that the PLL circuit is in the unlocked state.
The UNLK pin is high during unlocked periods and during the 1024/fs (seconds) required for the unlocked to locked
transition. The LSI performs the same processing during the locked to unlocked transition as it does when MUTE is
high.
• External circuits
Symbol
Value
R1
150
R2
5.1 k
R3
5.1 k
R4
24 k
C1
0.02
C2
0.1
Unit
Ω
µF
■ No products described or contained herein are intended for use in surgical implants, life-support systems, aerospace
equipment, nuclear power control systems, vehicles, disaster/crime-prevention equipment and the like, the failure of
which may directly or indirectly cause injury, death or property loss.
■ Anyone purchasing any products described or contained herein for an above-mentioned use shall:
➀ Accept full responsibility and indemnify and defend SANYO ELECTRIC CO., LTD., its affiliates, subsidiaries and
distributors and all their officers and employees, jointly and severally, against any and all claims and litigation and all
damages, cost and expenses associated with such use:
➁ Not impose any responsibility for any fault or negligence which may be cited in any such claim or litigation on
SANYO ELECTRIC CO., LTD., its affiliates, subsidiaries and distributors or any of their officers and employees
jointly or severally.
■ Information (including circuit diagrams and circuit parameters) herein is for example only; it is not guaranteed for
volume production. SANYO believes information herein is accurate and reliable, but no guarantees are made or implied
regarding its use or any infringements of intellectual property rights or other rights of third parties.
This catalog provides information as of February, 1996. Specifications and information herein are subject to
change without notice.
PS No. 5236-10/10