No. 6015-20/31

LC78622NE

Audio output level = 20 log

[dB]

For example, the formula below calculates the time required for the attenuation level to increase from 00H to EEH

when a 4STEP UP command is executed. Note that the control microprocessor must provide enough of a time

margin for this operation to complete before issuing the next attenuation level set command.

≈ 21.6 ms

Note: Setting the attenuation level to values of EFH or higher is disallowed to prevent overflows in one-bit D/A

converter calculations from causing noise.

14. Mute Output; Pin 35: MUTEL/CONT7, pin 42: MUTER/CONT8

15. C2 Flag Output; Pin 30: C2F

C2F output flag information in 8-bit units.

16. Digital Output Circuit; Pin 31: DOUT

This is an output pin for use with a digital audio interface. Data is output in the EIAJ format. This signal has been

processed by the interpolation and muting circuits. This pin has a built-in driver circuit and can directly drive a

transformer.

• The DOUT pin can be locked at the low level by issuing a DOUT OFF command.

• The UBIT information in the DOUT data can be locked at zero by issuing a UBIT OFF command.

• The DOUT data can be switched to data for which interpolation and muting processing have not been performed

by issuing a CD-ROM XA command.

• When searching and when returning the pickup to its initial position, there are cases when the frequency output

data will contain a parity error and locking is lost temporarily. To prevent this, we recommend directly executing a

UBIT OFF ($41) command and then directly executing a UBIT ON ($40) command when searching and when

returning the pickup to its initial position.

17. Mute Control Circuit

Inputting the above command mutes the audio level (MUTE -

∞ dB). Since zero-cross muting is used, there is very

little noise associated with this operation. The IC defines zero cross to be the ranges where the upper 7 bits of the

data are all zeros or all ones. Note that the MUTE -12 dB instruction supported by the LC78620E has been removed

from this product.

238 level

× 4STEP UP

44.1 kHz

ATT DATA

100H

MSB

LSB

Command

RES = low

0 1 0 0 0 0 1 0

DOUT ON

q

q

0 1 0 0 0 0 1 1

DOUT OFF

0 1 0 0 0 0 0 0

UBIT ON

q

q

0 1 0 0 0 0 0 1

UBIT OFF

1 0 0 0 1 0 0 0

CDROM-XA

1 0 0 0 1 0 1 1

ROMXA-RST

q

q

MSB

LSB

Command

RES = low

0 0 0 0 0 0 0 1

MUTE: 0 dB

0 0 0 0 0 0 1 1

MUTE: –

∞ dB

q

q