AK2347B Datasheet, PDF (9/34 Pages) Asahi Kasei Microsystems – Two-way Radio Audio & Sub-Audio Processor

ASAHI KASEI
[AK2347B]
12. Analog Characteristics
Unless otherwise specified, the following apply: MCK=3.6864MHz, f=1kHz, Emphasis: on,
Compandor: on, Scrambler: off, VR1=VR2=VR3=VR4=0dB, HPF=LMT=1 with the external circuit
shown in page.28 to 32.
“dBx” is a standardized notation to match the operating voltage and is defined by equation 0dBx =
-5+20log(VDD/2)dBm. 0dBm=0.775Vrms.
1) TX Audio system characteristics
Parameter
Condition
Standard input level @TXINO, EXTINO
Absolute gain
Distortion
Limit level
Compressor linearity
Compressor distortion
Noise level with no
signal input
VR1
Attenuation error
VR2 ATT error
(VR24,23,22,21,20)
VR2 ATT error
(VR25=0)
TXINO to MOD
EXTIN to MOD
EXTIN to MOD, EXTINO=-3dBx
When LMT is set to 0
30kHz Low-pass filtering
EXTIN to MOD
Without external R adjustment
With external R adjustment
TXINO to MOD
TXINO=-44dBx
TXINO=-50dBx
Relative value to 0dB for MOD
level of -10dBx TXINO.
TXINO to MOD
TXINO=-10dBx
30kHz Low-pass filtering
TXINO to MOD
C-Message filtering
TXINO to MOD
-6.0 dB to 4.5dB, 1.5dB/step
TXINO to MOD
-3.2dB to +3.0dB, 0.2dB/step
TXINO to MOD
Relative value when -6.4/0dB
is set
Min.
-1.5
-1.5
-8.6
-20.0
-24.0
-1.5
-0.2
-6.8
Typ.
-10
0
0
-7.6
-17.0
-20.0
-6.4
Max.
+1.5
+1.5
-35
-6.6
-6.6
-14.0
-16.0
-35
-36.5
+1.5
+0.2
-6.0
Units
dBx
dB
dB
Remarks
dB
dBx
dB
dB
dBm
dB
dB
dB
2) RX Audio system characteristics
Parameter
Condition
Standard Input Level
Absolute gain
@RXINO
RXINO to FILTERO
RXINO to RXOUT
Expander linearity
Expander distortion
Noise level with no
signal input
RXINO to RXOUT
RXINO=-25dBx
RXINO=-30dBx
Relative value to 0dB for RXOUT
level of -10dBx RXINO
RXINO to RXOUT
RXINO=-5dBx
30kHz Low-pass filtering
RXINO to RXOUT
C-Message Filtering
Min.
-1.5
-1.5
-33.0
-45.0
Typ.
-10
0
0
-30.0
-40.0
Max.
+1.5
+1.5
-27.0
-35.0
-35
-70
Units
dBx
dB
dB
Remarks
dB
dB
dBm
MS1419-E-00
-9-
2012/05