NPC SM6451BV Datasheet

SM6451BV

NIPPON PRECISION CIRCUITS INC.

Audio Variable V olume IC

OVERVIEW

The SM6451BV is a 3-wire serial-controlled electronic variable volume IC for audio applications. It provides
electronic volume control for a stereo system (left and right channels), and independent channel attenuation
and muting, with greatly enhanced digital zip noise suppression. The chip address function allows up to four
SM6451BV devices to be connected and individually controlled over the 3-wire control interface from a single
CPU. It is available in 16-pin VSOP packages.

FEATURES

■

Stereo inputs and outputs

■

Attenuation function

• 2-channel independent control

• 1.0 dB/step over 80 steps

• 0 to − 80 dB range

■

Mute function

■

3-wire serial data control (MDT, MCK, MLEN)

■

Chip addressing (up to 4 devices can be connected
in parallel)

■

Low noise

• 0.003 % THD + noise

• 12 µ Vrms residual noise

■

2.5 to 3.6 V single power supply

■

Silicon-gate CMOS process

PINOUT

(T op V iew)

RSTN

1

16

ADRS1
ADRS2

6451BV

DVDD

LOUT

LIN

AVDD

8

VRL VRR

9

MDT
MCK
MLEN
DVSS
ROUT
RIN
AVSS

APPLICATIONS

■

Audio equipment

ORDERING INFORMATION

De vice Pack ag e

SM6451BV 16-pin VSOP

PACKAGE DIMENSIONS

(Unit: mm)

16 pin VSOP

4.4 0.2

6.4 0.2

0.275TYP

5.1 0.2

0.65

0.22

+ 0.10

- 0.05

0.10

0.12

M

1.15 0.1

0.10 0.05

0.5 0.2

0.15

+ 0.1

- 0.05

010

NIPPON PRECISION CIRCUITS—1

BLOCK DIAGRAM

SM6451BV

DVDD DVSS

LIN

Attenuation

Control

1/2VDD

MLEN

MCK

MDT

Attenuation Decoder

Interface Control

Circuits

RSTN

Decoder

Address

ADRS1

Chip

ADRS2

1/2VDD

RIN

Attenuation

Control

AVDD AVSS

PIN DESCRIPTION

Number Name I/O

1 RSTN Ip D System reset input (LOW -level reset)
2 ADRS1 Ip D Chip address set 1
3 ADRS2 Ip D Chip address set 2
4 D VD D – D Digital supply
5 LOUT O A Left-channel audio output
6 LIN I A Left-channel audio input
7 AV D D – A Analog supply

8 VRL O A

9 VRR O A

10 AVS S – A Analog ground
11 R IN I A Right-channel audio input
12 R O U T O A Right-channel audio output
13 D VS S – D Digital ground
14 MLEN Ip D Microcontroller latch enable input
15 MCK Ip D Microcontroller clock input
16 M D T Ip D Microcontroller data input

1. Ip = input pin with pull-up, A = analog, D= digital

1

A/D

1

Left-channel reference voltage (0.5V
between VRL and AV SS.

Right-channel reference voltage (0.5V
between VRR and AV SS.

Reference

Voltage

LOUT

VRL

VRR

ROUT

Description

). Connect a 10 µF capacitor

DD

). Connect a 10 µF capacitor

DD

NIPPON PRECISION CIRCUITS—2

−

−

−

−

−

°

°

SPECIFICATIONS

Absolute Maximum Ratings

−

° C

SM6451BV

DVSS = AVSS = 0 V, DVDD = AVDD = V

DD

Parameter Symbol Rating Unit

Supply voltage V
Input voltage V
Po w er dissipation P
Storage temperature T
Soldering temperature T
Soldering time t

Recommended Operating Conditions

DVSS = AVSS = 0 V, DVDD = AVDD = V

Parameter Symbol Rating Unit

Supply voltage V
Supply voltage deviation DV
Operating temperature T

DD

DD

AV

DC Characteristics

DD

DD

IN

D

stg

sld

sld

DD

, DV

opr

SS

AV

SS

0.3 to 7.0 V

V

SS

0.3 to V

+ 0.3 V

DD

150 m W

55 to 125

255

10 s

2.5 to 3.6 V
±0.1 V

40 to 85

C
C

DVDD = AVDD = V

= 2.5 to 3.6 V, V

DD

Parameter Symbol Condition

Data transfer stopped, MDT, MCK,
MLEN, RSTN, ADRS1, ADRS2 = V

ADRS1 = ADRS2 = 0V, 0.8 Vrms
analog input, ATT = 0 d B , data transfer
active

IH

IL

I

V

IL

I

IH

= 0 V – 70 15 0 µ A

IN

V

= V

IN

DVDD Current consumption

AVDD Current consumption I
HIGH-level input voltage

L O W -level input voltage
Input current

1

Input leakage current

1

1

1

I

DDD1

I

DDD2

DDA

V
V

1. MD T, MCK, MLEN, RSTN, ADRS1, ADRS2

= 0 V, Ta = − 40 to 85 ° C

SS

DD

DD

Rating

min typ max

– 0.2 1.0 µA

– 0.4 1.0 m A
– 1.9 5.5 m A

0.7V

DD

– – 0.3V

––V

DD

– – 1.0 µ A

Unit

V

NIPPON PRECISION CIRCUITS—3

AC Digital Characteristics

SM6451BV

DVDD = AVDD = V

= 2.5 to 3.6 V, V

DD

= 0 V, Ta = − 40 to 85 ° C

SS

Serial inputs (MDT, MCK, MLEN)

Parameter Symbol

MCK, MLEN rise time t
MCK, MLEN fall time t
MDT setup time t
MDT hold time t
MLEN setup time t
MLEN hold time t
MLEN LOW-level pulsewidth t
MLEN HIGH-level pulsewidth t

MDT

tMDS

tMDH

r

f

MDS

MDH

MCS

MCH

MEWL

MEWH

Rating

Unit

min typ max

– – 100 ns

– – 100 ns
50 – – ns
50 – – ns
50 – – ns
50 – – ns
50 – – ns
50 – – ns

0.5VDD

MCK

tMCS

tMEWL

tf tr

MCK

MLEN

0.9VDD

0.1VDD

Reset input (RSTN)

Parameter Symbol

RSTN LOW-level pulsewidth t

RSTN

tMCH

tMEWH

0.5VDD

0.5VDDMLEN

0.9VDD

0.1VDD

Rating

min typ max

100 – – ns

0.5VDD

Unit

NIPPON PRECISION CIRCUITS—4