Document
AN6425K
Speech Network Circuit
s Overview
The AN6425K is a high-function speech network IC with speaker amplifier. It incorporates a transmitter-system non-linear circuit, receiver digital VRs, etc. and is suitable for realizing the multifunctional telephone sets.
26.7±0.3 1 2 3 4 5 6 7 8 9 10 11 12 13 14 8.4±0.3 28 27 26 25 24 23 22 21 20 19 18 17 16 15 Unit : mm 0.5±0.1 0.9±0.25 1.05±0.25 4.8±0.25 3.05±0.25
0.3
+ 0.1 5 – 0.0
s Features
• Speech network IC for the multifunctional telephone sets • Capable of interfacing with the light-weight small receivers
and ECM transmitters
• Built-in 2V REG constant voltage source (2V typ) for ECM • Built-in non-linear circuits in the transmitter and receiver
systems in order to eliminate ambient noises
• Built-in speaker amplifier and capable of driving with a main
wire current
• Built-in hold-tone amplifier, key-in-tone amplifier, and
DTMF transmitter, and capable of setting the mode with the control pins • Automatic gain control (automatic pad function) according to a circuit curret • Built-in tertiary active filter circuit and capable of sending a DTMF circuit with much higher harmonic at a low distortion factor • Built-in single touch receiver volume-up function (about 6dB)
3 to 15˚ 10.16±0.25
28-pin Shrunk DIL Plastic Package (SDIP028-P-0400B)
s Block Diagram
VL
28 27 26 25 24 23 CLASS B BTL SP Amp. CLASS A Push pull 1V 2V REG 2V HT TT in +
REC DRIVER REC DRIVER
22
21
20 80kΩ –
19
18
17
16
15
+ –
D5dB D3dB D6dB REC in DVR
+
– 30kΩ
2kΩ
30kΩ
2kΩ
40kΩ KT
4kΩ
1V REFF 1V
VL
Battery Selector 65kΩ 1 2 3 4 5 6
SEND Amp
D12 dB
Filter Amp. D3dB MUTE
MIC in
Logic INV NAND
7
8
9
10
11
12
13
14
GND
1.778
s Absolute Maximum Ratings (Ta=25˚C)
Parameter Supply voltage Supply current Power dissipation Operating ambient temperature Storage temperature * VCC × ICC <1200mW Symbol VL IL PD Topr Tstg Rating 14.4 * 120 * 1200 * –20 to + 65 –55 to +150 Unit V mA mW ˚C ˚C
s Recommended Operating Range (Ta=25˚C)
Parameter Operating supply voltage range Symbol VL Range 3 to 12V
s Electrical Characteristics (Ta=25˚C)
Parameter Receiver gain Symbol GV (REC) THD (REC) VO (REC) AP (REC) MUTE (REC) Condition Open between the Pins19 and 20. Measure the output between the Pins22 and 23 when a signal (–55dBm) is input to the Pin18.
Open between the Pins19 and 20. Measure the output distortion factor between the Pins 22 and 23 when a signal (–55dBm) is input to the Pin18.
min 48
typ 50.5
max 53
Unit dB
Receiver distortion factor
1
5
%
Receiver maximum output voltage
D Automatic pad
D Receiver noise prevention
Receiver D digital VR Receiver noise output Transmitter gain
DVR Vno (REC) GV (SEND) THD (SEND) VO (SEND) AP (SEND) Vno (SEND) GV (HOLD) GV (TOUCH) THD (TOUCH)
Input a signal to the Pin18 and measure the output between the Pins22 and 23 at an output distortion factor of 5%. Input a signal (–45dBm) to the Pin18 and measure an output change between the Pins22 and 23 when IL changes from 80mA to 30mA. Input a signal (–45dBm) to the Pin18 and measure an output change between the Pins 22 and 23 when the Pin12 changes from no microphone input signal to –40dBm. Input a signal (–45dBm) to the Pin18 and measure an output change between the Pins 22 and 23 when the Pin12 is set from H to L. Measure the output between the Pins22 and 23 when there is no signal at the Pin18. Open bitween the Pins3 and 6. Measure the output between the Pins28 and 1 when a signal (–45dBm) is input to the Pin12.
Open between the Pins3 and 6. Measure the output distortion factor between the Pins28 and 1 when a signal (–45dBm) is input to the Pin12.
0
+3
dBm
–6
–3
–1.5
dB
–7
–5
–3
dB
4
6 –50
8 –45 45
dB dBm dB
40
42.5
Transmitter distortion factor
1.5
5
%
Transmitter maximum transmission level
Transmitter D automatic pad Transmitter noise prevention HOLD TONE gain
TOUCH TONE gain
TOUCH TONE distortion factor
Input a signal to the Pin12 and measure the output between the Pins28 and 1 at an output distortion factor of 5%. Input a signal (–35dBm) to the Pin12 and measure an output change between the Pins 28 and 1 when IL changes from 80mA. Measure the output between the Pins28 and 1 when there is no signal at the Pin18. Ground the Pin24. Input a signal (–30dBm) to the Pin17 and measure the output change between the Pins 28 and 1. Ground a signal (–45dBm) to the Pin16 and measure the output between the Pins28 and 1. Ground the Pin14. Input a signal (–45dBm) to the Pin16 and measure the output distortion factor between the Pins 28 and 1.
2
5
dBm
–6
–3 –65
–1.5 –60 29.5
dB dBm dB
23.5
26.5
39
41.5
44
dB
1
3
%
* IL=30mA and Freq=1kHz unless otherwise specified.
s Electrical Characteristics (cont.) (Ta=25˚C)
Parameter TOUCH TONE D automatic pad Symbol AP (TOUCH) GV (SP) THD (SP) Condition Ground the Pin14. Input a signal (–45 dBm) to the Pin16 and measure an output change between the Pins 28 and 1 when IL changes from 80mA to 30mA. Grou.