ASAHI KASEI

[AK4520A]

0163-E-00

1997/3

- 1 -

AK4520A

100dB 20Bit Stereo

ADC & DAC

General Description

The AK4520 is a stereo CMOS A/D & D/A converter for middle-range MD/DAT, Surround System and musical
instruments. Signal inputs and outputs are single-ended. The DAC outputs are analog filtered to remove out of
band noise. External components are minimized.

Features

Stereo ADC

- 64x Oversampling
- S/(N+D): 90dB at 5V, 86dB at 3V
- Dynamic Range: 100dB at 5V, 96dB at 3V
- S/N: 100dB at 5V, 96dB at 3V
- Digital HPF for offset cancel

Stereo DAC

- 128x Oversampling
- 2nd order SCF + 2nd order CTF
- Digital de-emphasis for 32kHz, 44.1kHz, 48kHz sampling
- S/(N+D): 90dB at 5V, 90dB at 3V
- Dynamic Range: 100dB at 5V, 96dB at 3V
- S/N: 100dB at 5V, 96dB at 3V

High Jitter Tolerance

Sample Rate Ranging from 16kHz to 54kHz

Master Clock: 256fs or 384fs

2.7 to 3.6V or 4.5 to 5.5V supply

Low Power Dissipation: 255mW

Small 28pin VSOP Package

ASAHI KASEI

[AK4520A]

0163-E-00

1997/3

- 3 -

PIN/FUNCTION

No.

Pin Name

I/O

Function

VREFH

Positive Voltage Reference Input Pin, VA

Used as a positive voltage reference by ADC & DAC. VREFH is connected

externally to filtered VA.

VREFL

Negative Voltage Reference Input Pin, AGND

Used as a negative voltage reference by ADC & DAC. VREFL is connected

externally to AGND.

AINR+

Rch Analog Positive Input pin

AINR-

Rch Analog Negative Input Pin

AINL+

Lch Analog Positive Input pin

AINL-

Lch Analog Negative Input Pin

Analog Power Supply Pin

AGND

Analog Ground pin

DIF0

Audio Data Interface Format Pin

DIF1

Audio Data Interface Format Pin

LRCK

Input/Output Channel Clock Pin

SCLK

Audio Serial Data Clock Pin

SDTI

Audio Serial Data Input Pin

SDTO

Audio Serial Data Output Pin

MCLK

Master Clock Input Pin

DEM0

De-emphasis Frequency Select Pin

DEM1

De-emphasis Frequency Select Pin

TST3

TST2

TST1

I/O

Test Pins (Pull down pins)

Must be left open or connected to DGND.

Digital Power Supply Pin

DGND

Digital Ground Pin

PWDA

DAC Power-Down Mode Pin

PWAD

ADC Power-Down Mode Pin

CMODE

Master Clock Select Pin

"H": 384fs, "L": 256fs

AOUTL

Lch analog output pin

AOUTR

Rch analog output pin

VCOM

Common Voltage Output Pin, VA/2

Note: All input pins except pull-down pins should not be left floating.

ASAHI KASEI

[AK4520A]

0163-E-00

1997/3

- 4 -

ABSOLUTE MAXIMUM RATINGS

(AGND,DGND=0V; Note 1 )

Parameter

Symbol

min

max

Units

Power Supplies: Analog

Digital

|AGND-DGND|

GND

-0.3

6.0

0.3

Input Current, Any Pin Except Supplies

IIN

Analog Input Voltage

VINA

-0.3

VA+0.3

Digital Input Voltage

VIND

-0.3

VD+0.3

Ambient Temperature (power applied)

-10

Storage Temperature

Tstg

-65

150

Note: 1 . All voltages with respect to ground.

WARNING: Operation at or beyond these limits may result in permanent damage to the device. Normal

operation is not guaranteed at these extremes.

RECOMMENDED OPERATING CONDITIONS

(AGND,DGND=0V; Note 1 )

Parameter

Symbol

min

typ

max

Units

3V operation

Analog

Digital

2.7

3.0

3.6

Power Supplies:

(Note 2 )

5V operation

Analog

Digital

4.5

5.0

5.5

Note: 1 . All voltages with respect to ground.

2 . The power up sequence between VA and VD is not critical.

ASAHI KASEI

[AK4520A]

0163-E-00

1997/3

- 5 -

ANALOG CHARACTERISTICS

(Ta=25

C; VA,VD=5.0V; AGND=DGND=0V; VREFH=VA; VREFL=AGND; fs=44.1kHz; SCLK=64fs,

Signal Frequency=1kHz; 20bit Data; Measurement frequency=10Hz

20kHz; unless otherwise specified)

Parameter

min

typ

max

Units

ADC Analog Input Characteristics: Differential Inputs; Analog Source Impedance=470

Resolution

Bits

S/(N+D) (-0.5dB Input)

(Note 3 )

VA=3V

VA=5V

DR (-60dB Input, A-Weighted)

(Note 4 )

VA=3V

VA=5V

100

S/N (A-Weighted)

(Note 4 ,5 )

VA=3V

VA=5V

100

Interchannel Isolation

110

Interchannel Gain Mismatch

0.1

0.3

Gain Drift

ppm/

Input Voltage

AIN=0.6x(VREFH-VREFL)

VA=3V

VA=5V

1.7

2.85

1.8

3.0

1.9

3.15

Vpp

Input Resistance

Power Supply Rejection (Note 6 )

DAC Analog Output Characteristics:

Resolution

Bits

S/(N+D)

VA=3V

VA=5V

DR (-60dB Output, A-Weighted)

(Note 4 )

VA=3V

VA=5V

100

S/N (A-Weighted)

(Note 7,5 )

VA=3V

VA=5V

100

Interchannel Isolation

110

Interchannel Gain Mismatch

0.1

0.3

Gain Drift

ppm/

Output Voltage

AOUT=0.626x(VREFH-VREFL)

VA=3V

VA=5V

1.76

2.94

1.88

3.13

1.99

3.32

Vpp

Load Resistance

Load Capacitance

Power Supply Rejection (Note 6 )

Note: 3 . In case of single ended input, S/(N+D)=84dB(typ, @VA=5V).

4 . In case of 16bit, DR and S/N of ADC are 98dB. DR of DAC is 98dB.
5 . S/N measured by CCIR-ARM is 96dB at each converter and 94dB at ADC to DAC loopback.
6 . PSR is applied to VA,VD with 1kHz, 50mVpp. VREFH/VREFL pin is held a constant voltage.
7 . As the input data is "0", S/N is 100dB regardless of resolution.

Part Number AK4520