NJW1128 Datasheet, PDF (1/13 Pages) New Japan Radio – Voice Switched Speakerphone Circuit with Speaker Amplifier

NJW1128
Voice Switched Speakerphone Circuit
with Speaker Amplifier
! GENERAL DESCRIPTION
! PACKAGE OUTLINE
The NJW1128 is a Voice Switched Speakerphone Circuit. It includes all of functions
processing a high quality hands–free speakerphone system, such as the necessary
amplifiers ( Mic , Receive ,Line, Speaker ), attenuators, level detectors functions.
The NJW1128 is controllable independently power-down of the speaker amplifier and
the entire IC excluding the speaker amplifier.
All external capacitors are sufficient small so that ceramic capacitors are applied.
! APPLICATION
•Video Door Phone
•Conference System
•Wireless Application
•Security System
NJW1128FR3
! FEATURES
q Operating voltage range
q Attenuator gain range between Transmit and Receive
q Speaker amplifier
q Microphone amplifier with mute function
q Force to Receive, Transmit, or Idle modes
q Mode –watching monitor
q Background noise monitor for each path
q 4-point signal sensing
q Chip disable Pin powers down the entire IC excluding
the speaker amplifier
q Speaker switch Pin power down the speaker amplifier
q Microphone and Receive Amplifiers pinned out for flexibility
q Package Outline
3.9 to 5.5V
52dB
LQFP48-R3
! BLOCK DIAGRAM
C8 R4
100n 3k
M ic rophone
M ICIN
R5
300 k
C9
10 0n
R6
5.1k
MICOUT TLI2
C1 0 C11 R 8
R9
100n 100n 5 .1k 51k
R7
5 .1k
TLI1 TXO
Cf L
L II
L iO-
L iO+
MUT
V+ :MU TE
GND :AC TIVE
V⁺
R2
3 00k
C2
1µ
C5
1 00n
C6
100n
C4
1u
M UT
TL O2
RL O2
CPT
VR EF
M ic
Am plifier
Tx Atten uato r
Level
D et ect or
B a ckground
Noi seMon itor
At t enuat or
Control
VR EF
-1
L ine Am plifi er
Backgrou nd
No iseM onitor
Line Out
SPV⁺
C 22
SPV⁺
1µ
V⁺
C 12
V⁺
1µ
Monit or
C7
CT
1µ
V⁺
RTSW
C21
C PR
1µ
V⁺ :Reciv e
GND :Trensm it
Open :idle
CD
V+ :AC TIVE
GND :Power Down
C20
1µ
C1
VREF
1µ
CD
R3
V^{+ C3 300 k}
1µ _SPS
SPSW
V+ :ACTIVE
V⁺
GN D :Powe r Down
R3
300 k
B IAS
L evel
Detector
Speaker Ampl ifier
-1
V RE F
Rx Attenuator
1.2µA
Receiv e
Am pli fier
SPO+
S PO -
CfS
R10
51 k
SPI
RXO RL I2
R 12
R11 C 13 C1 4 ^5.1k
5.1k 10 0n 100n
VL C
R 13
5.1k
RVL C
R LI1
C15
100n
FO
R14
5.1k
CfR
T LO1
RLO1
C20
100 n
C 19
100 n
SPGN D
GND
V RE F
FI
R 15
5. 1k
C 16
100n
Recive In
Spea ke r
Ver.1.4 – 1 –