SAMSUNG KA8601C

KA8601C
SPEAKER PHONE WITH SPEECH NETWORK
INTRODUCTION
48-SDIP-600
The KA8601C is a monolithic integrated circuit for use in high performance speaker phone system.
The KA860lC consists of speaker phone and speech network. Speaker
phone includes attenuators, amplifiers, level detectors, attenuator
control, hybrid amplifiers, regulator and AGC circuit. Speech network
includes transmit amp, receive amp, voltage regulator for dialer, side
tone control, and line equalizer.
FEATURES
• Speaker Phone
- Low Operating Voltage (3.0 ~ 6.5V)
- High Attenuator Gain Range (52dB)
- Improved Sensitivity (Four-point Signal Sensing)
- Chip Disable for Active or Standby Operation
- Microphone Amp Gain set by External Components
• Speech Network
- Low Operating Voltage (1.5V : speech)
- Regulated Voltage for Dialer (Typically 3.3V)
- Transmit, Receive, Side Tone Gains set by
External Components
- Mute Input for DTMF Dialing
ORDERING INFORMATION
Device
Package
Operating Temperature
KA8601C
48-SDIP-600
- 25°C ~ + 75°C
VDD
13
14
MICO
TXI
sidetone
amp
POWER
12
GND
23
24
VCC
20
RXI
MS
19
RXO-
22
18
NC
ZB
17
NC
RXOSUM 21
16
REC
amp
15 TX
amp1
AGC
RXO+
mic
amp
1.7Vreg
RX
amp
11
AGC
10
7
VL
MICI+
6
VI
MICI-
5
MT
9
4
FO
LC
3
FI
VR
2
CD
SPEECH NET8 WORK PART
1
DTO+
DC level
shift
FILTER
TX
amp2
hybrid
amp 2
ATTENUATOR
CONTROLLER
BNM : Back Noise Monitor
TXO ATT
3.3Vreg
TX
Attenuator
BNM
AGC
BNM
25
26
TXI ATT
27
PD TX
VB
28
29
DETI TX2
DETO TX2
31
30
DETO RX2
32
mic
amp
level
detector
MICI
37
DETI RX2
MICO
38
CT
DETI TX1
39
33
DETO TX1
40
34
DETO RX1
41
VC
DETI RX1
42
MT
PD RX
43
36
GND
44
35
RXI ATT
45
RX
Attenuator
hybrid
amp 1
SPEAKER PHONE PART
level
detector
RXO ATT
46
47 DTI
48
DTO-
BLOCK DIAGRAM
KA8601C
SPEAKER PHONE WITH SPEECH NETWORK
PIN CONFIGURATION
DTO+
1
48
DTO-
CD
2
47
DTI
FI
3
46
RXOATT
FO
4
45
RXIATT
R4
5
44
GND
VI
6
43
PDRX
VL
7
42
DETIRX1
LC
8
41
DETORX1
VR
9
40
DETOTX1
MICI-
10
39
DETITX1
MICI+
11
38
MICO
GND
12
37
MICI
MICO
13
36
MT
TXI
14
35
VC
AGC
15
34
CT
RXO+
16
33
DETIRX2
NC
17
32
DETORX2
NC
18
31
DETOTX2
RXO-
19
30
DETITX2
RXI
20
29
PDTX
RXOSUM
21
28
VB
ZB
22
27
TXIATT
MS
23
26
TXOATT
VCC
24
25
VDD
KA8601C
Fig. 2
PIN DESCRIPTION
Pin No
Symbol
Description
1
DTO+
2
CD
3
FI
Filter input.
4
FO
Filter output.
5
MT
Mute input. A logic “1” sets normal speech mode.
6
VI
7
VL
8
LC
Resistor at this pin set the DC characteristics of the circuit.
9
VR
A 1.7 volt regulated output which can be used to bias the mic.
10
MICI-
Inverting differential input to the mic amp.
11
MICI+
Non-inverting differential input to the mic amp.
12
GND
Ground pin for the speech network.
13
MICO
Mic amp output.
14
TXI
15
AGC
Output of the second hybrid amplifier.
Chip Disable. A logic low (<0.8V) sets normal operation.
A resistor connected from this pin to VSS sets the AC terminating impedance.
Power supply for the speech network. Supply voltage is derived from loop current.
T X amp output operates on this pin.
Input to the TX amp from the Mic amp.
Loop current sensing input.
KA8601C
SPEAKER PHONE WITH SPEECH NETWORK
PIN DESCRIPTION (continued)
Pin No
Symbol
Description
16
RXO+
17
NC
No connection.
18
NC
No connection.
19
RXO-
20
RXI
21
RXO SUM
22
ZB
Input to the RX current amp.
23
MS
Mode select input. A logic “1” → pulse dialing, A logic “0” → tone (DTMF) dialing.
24
VCC
A supply voltage pin for the speaker phone part.
25
VDD
A regulated 3.3 volt output for an external dialer.
26
TXOATT
Output of the TX attenuator.
27
TXIATT
Input to the TX attenuator.
28
VB
29
PD TX
RX amp non-inverting differential output.
RX amp inverting differential output.
Input to the RX amp.
Summed output of the RX current amp.
This voltage is a system AC ground, and biases the volume control. A filter cap is required.
An RC at this pin sets the time constant for the TX background monitor.
30
DETITX2
Input to the TX level detector on the mike/speaker side.
31
DETOTX2
Output of the TX level detector on the mike/speaker side.
32
DETORX2
Output of the RX level detector on the mike/speaker side.
33
DETIRX2
Input to the RX level detector on the mike/speaker side.
34
CT
35
VC
This pin sets the response time for the circuit to switch modes.
Volumn control input.
Mute input. A logic low (<0.8V) sets normal operation. A logic high (>2.0V) mutes the
36
MT
37
MICI
Input and summing node of the mic amp.
38
MICO
Output of the mic amp is set by external resistors.
39
DETTX1
40
DETOTX1
Output of the TX level detector on the line side.
41
DETORX1
Output of the RX level detector on the line side.
42
DETIRX1
Input to the RX level detector on the line side.
43
PD RX
A RC at this pin sets the time constant for the RX background monitor.
44
GND
Ground pin for the speaker phone part.
45
RXI ATT
Input to the RX attenuator and dial tone detector.
46
RXO ATT
Output of the RX attenuator.
47
DTI
48
DTO -
mic amp.
Input to the TX level detector on the line side.
Input and summing node of the mic amp.
Output of the first hybrid amplifier.
KA8601C
SPEAKER PHONE WITH SPEECH NETWORK
ABSOLUTE MAXIMUM RATINGS
Characteristic
Symbol
Supply Voltage
Speaker
Phone
Value
Unit
VCC
- 1.0 ~ + 7.0
V
Voltage at VC
VI (VC)
- 1.0 ~ VCC + 0.5
V
Voltage at CD,MT
VI (CM)
-1.0 ~ VCC + 1.0
V
Voltage at TXI, RXI, HFI
VI (TRH)
- 0.5 ~ VCC + 0.5
V
VCC
- 1.0 ~ + 12
V
V
Supply Voltage
Speech
Supply Voltage for dialer
Network
Voltage at MTS, MS
Current Through VL, LC
VDD
- 1.0 ~ + 6.0
VI (MS)
- 1.0 ~ VDD + 0.5
V
II (VL, LC)
130
mA
Current into ZB
II (ZB)
3
mA
Operating Temperature
T OPR
- 25 ~ + 75
°C
Storage Temperature
T STG
- 65 ~ + 150
°C
ELECTRICAL CHARACTERISTICS
Characteristic
(Ta = 25°C)
Symbol
Test Conditions
Min
Typ
Max
Unit
SPEECH NETWORK (Ta = 25°C, unless otherwise noted)
Line Voltage
VR Voltage
MF Operating Voltage
VL
VR
VDD (MF)
Speech Mode
IL = 30mA
3.0
3.9
4.7
Pulse Mode
IL = 120mA
8
9.8
11.5
Tone Mode
IL = 30mA
4.4
5.1
6.5
IL = 30mA
Speech Mode
1.55
1.7
1.85
VL = 4.5V
Tone Mode
3.0
3.3
3.8
IDD = 1.6mA
3.0
3.3
3.8
Speech Mode
0.5
1.1
2.0
IDD MF (MAX)
V
V
Tone Mode
MF Operating Current (Max)
V
IL = 30mA
Pulse Mode
2
2.8
4
Tone Mode
2
2.8
4
mA
MICO Bias Voltage
VBIAS (MPO)
IL = 30mA
Speech Mode
0.8
1.08
1.4
V
TXI Bias Voltage
VBIAS (TxTs)
IL = 30mA
Speech Mode
0.04
0.086
0.2
V
GV (MIC)
IL = 30mA
Speech Mode
27
30
33
dB
30
64
-
dB
dB
MIC Amp Gain
MIC Common Mode
Rejection Ratio
MIC Gain Reduction
T X Gain
T X Distortion
-
CMRR(MIC)
∆GV (MIC)
MT = 0V
GV (TX)
Speech Mode
THD TX
IL = 30mA
-10
-60
-
IL = 30mA
30
34.8
60
IL = 80mA
28
31
34
Speech Mode
-
-
2
IL = 30mA
-15
-10.5
-2
IL = 80mA
-17
-14
-10
dB
%
RX Gain
GV (RX)
Speech Mode
RX Distortion
THD RX
IL = 30mA
Speech Mode
-
-
2
%
Side Tone Gain
GV (ST)
IL = 30mA
Speech Mode
-
10
15
dB
dB
KA8601C
SPEAKER PHONE WITH SPEECH NETWORK
ELECTRICAL CHARACTERISTICS
Characteristic
Side Tone Rejection
MUTE Input Impedance
(Continued)
Symbol
Test Condition
Min
Typ
Max
RST
20
25
-
dB
ZI (MUTE)
-
60
-
KΩ
MUTE Input Low Voltage
VIL (MUTE)
-
1.0
MUTE Input High Voltage
VIH (MUTE)
VDD
V
-0.3
MS Input Low Voltage
VIL (MS)
MS Input High Voltage
VIH (MS)
LC Level Shift
Unit
∆ VLC
0.8
-
-
2.0
IL = 30mA
Speech Mode
2.1
2.9
3.5
Pulse Mode
2.1
2.9
3.5
Tone Mode
3.4
4.3
5.2
CD = 0.8V
-
5.5
8.0
CD = 2V
-
0.6
0.8
V
SPEAKER PHONE (Ta = 25°C, VCC = 5.0V, unless otherwise noted)
Operating Current
Reference Voltage
ICC
VCC = 6.5V
mA
1.8
2.1
2.4
1.5
1.7
1.9
-
1.3
-
VC = VB
4.0
6.0
8.0
VCC = 3.5V, VC = VB
4.0
6.0
8.0
VCC = 2.8V, VC = VB
-
-19
-11
∆GATT (RX)
VCC = 3.5V, to 5.0V
-0.5
0
+0.5
∆GATT AGC (RX)
VCC = 2.8V, to 5.0V
-
-25
-15
dB
-22
-20
-17
dB
VREF
IL = 1.0mA
VCC = 3.5V
RX Attenuator Gain
RX Attenuator Gain Change
RX Attenuator AGC Gain Change
RX Attenuator Gain (Idle Mode)
GATT (RX)
GATT RX (IM)
RX Attenuator Gain Range
GATT (RX)
RX Volume Control Range
GV CTL (RX)
RX DC Output Voltage
VC = VB
49
52
54
dB
27
35
-
dB
VO (RX)
-
VB
-
V
-
± 10
±150
mV
3.7
-
-
V
VRXI = 1V
-
-1.5
-1.0
V
-
0.5
3
%
RX Mode
-
+240
-
Idle Mode
-
0
-
T X Mode
-
-240
-
RX to TX Mode
RX DC Output High Voltage
VOH (RX)
VRXI = 3.5V
VOL (RX)
RX Mode Distortion
CT Voltage (with respect to VB)
THD RX
VCT
dB
VC = 0.1VB
∆VO (RX)
(with respect to VB)
dB
VC = VB (RX to TX Mode)
RX DC Output Voltage Change
RX DC Output Low Voltage
V
Dial Tone Detector Threshold
VTH (DET)
10
15
20
mV
T X Attenuator Gain
GATT (TX)
4.0
6.0
8.0
dB
T X Attenuator Gain Range
GATT (TX)
49
52
54
dB
VO (TX)
-
VB
-
V
∆VO (TX)
-
± 30
±150
mV
T X Output DC Voltage
T X Output DC Voltage Change
VC = VB, VRXI = 3.0V
mV
KA8601C
SPEAKER PHONE WITH SPEECH NETWORK
ELECTRICAL CHARACTERISTICS
Characteristic
(Continued)
Symbol
Test Conditions
Min
Typ
Max
Unit
T X Output High Voltage
VOH (TX)
VTXI = 3.5V
3.7
-
-
V
T X Output Low Voltage
VOL (TX)
VTXI = 1.0V
-
0.5
1
V
T X Mode Distortion
THDTX
-
0.8
3
%
MIC Voltage Gain
GV (MIC)
70
80
-
dB
MIC Output Offset Voltage
VOO (MIC)
-50
0
+50
mV
MIC Output High Voltage
VOH (MIC)
VMIC = 1.0V
3.7
-
-
V
MIC Output Low Voltage
VOL (MIC)
VMIC = 3.0V
-
-
200
mV
MIC Input Bias Current
IBIAS (MIC)
-
-40
-
nA
Muting (Gain)
GV (MUTE)
-55
-
-
dB
MIC Amp Distortion
THD MIC
-
0.15
-
%
MUTE Input High Voltage
VIH (MUTE)
2.0
-
VCC
V
MUTE Input Low Voltage
VIL (MUTE)
0
-
0.8
V
GV (HA)
60
80
-
dB
DTO-Output High Voltage
VOH (DTO -)
3.7
-
-
V
DTO-Output Low Voltage
VOL (DTO -)
-
-
250
mV
DTO+Output High Voltage
VOH (DTO +)
IO = -5mA
3.7
-
-
V
DTO+Output Low Voltage
VOL (DTO +)
IO = 5mA
-
-
250
mV
DTO Distortion
THD DTO
IO = -5mA
-
0.3
-
%
VIO (F)
IO = 5mA
-22
-90
0
mV
0
-50
-
mA
Open Loop Gain (Hybrid Amp)
Filter Offset Voltage
Filter Input Bias Current
VBIAS (F)
VMT = 2V, f = 1KHz
0.3KHz ≤ f ≤ 10KHz
KA8601C
SPEAKER PHONE WITH SPEECH NETWORK
APPLICATION INFORMATION
FUNCTION DESCRIPTION
SPEECH NETWORK
1. MICROPHONE AMPLIFIER
This microphone amplifier is equipped with a fixed gain (30dB). Its basic configuration is shown in figure 3.
MICI+
+
30dB
MICO
-
MIC20K
20K
MT
Fig .3
This amplifier has a mute function. If a mute signal from the dialer is inputted when the speech network is in the mute
mode, the microphone amplifier will be muted.
2. VOLTAGE REGULATOR (DIALER INTERFERENCE)
This voltage regulator has a minimum output voltage of 3.1 volts. When the dialer is not in motion, its minimum current
is 1.0mA, where as when the dialer is moving the minimum current is 2.2mA.
3. VOLTAGE REFERENCE
Generally when in the voltage reference mode, the microphone's bias voltage is used, but when in the TXlATT mode,
DC bias voltage is used. The output voltage of the voltage reference is a minimum of 1.6 volts.
SPEAKER PHONE
1. MICROPHONE AMPLIFIER
This device amplifies outside microphone signals, which are inputted while in the inverting mode. As it alters elements,
the microphone amplifier allows for them to be modulated. Its open loop gain is 80dB, while the band width is typically
1.0KHz. It has a mute function, and when operating in the mute mode at least 2.0V, the microphone amplifier gain
is reduced to around 40dB. If the mute mode is not used, it must connected with the ground.
Rf
MIC
Ri
MICO
+
MT
Bias Voltage
Fig. 4
KA8601C
2.
SPEAKER PHONE WITH SPEECH NETWORK
VOLUME CONTROL
The volume control can only be applied in the receive mode. If the voltage of the VC mode is the same as the VB, the
receive attenuator gain is maximized and the transmit gain is minimized. At the same time, if the VC mode voltage is
less than the VB, the receive attenuator gain is reduced.
VB
VC
KA8601C
VOLUME
Fig. 5
3.
VOICE DETECTION FUNCTION
The voice detection function compares the microphone amplifier output level with the outside audio amplifier level
and the transmit attenuator output level with the receive attenuator input level, after which they are inputted into the
control box. The block diagram of the voice detection function is as follows:
DETO RX 1
DETIRX 1
PDTX
PDRX
DETO TX 1
Background
Noise Monitor
A1
A3
DETI TX
1
Log Amp
Log Amp
Comparator
Comparator
C1
C2
CO1
CO2
CO3
CO4
Log Amp
Log Amp
DETITX 1
Attenuator Control Box
A2
A4
DETI RX 1
DETO TX 1
DETO TX 1
Fig. 6
It is useful to use a background noise monitor when high background noise occurs. When the input signals to the
background noise monitor are increased, voltage for the PDRX (PDTX) mode is stably increased. The increase time
is determined by 100KΩ and 47µF.
4.
ATTENUATOR CONTROL BOX
In figure 6, each signal coming into the log amplifier is amplified and then inputted into the comparator (C1, C2). The
comparator compares the amplified signal levels, after which they are inputted into the attenuator control box. The
attenuator control box processes these signals (CO1, CO2, CO3, CO4) as logic signals, and which are put into one
of the following modes:
KA8601C
SPEAKER PHONE WITH SPEECH NETWORK
1. Receive Mode
2. Transmit Mode
3. Slow Idle Mode
4. Fast Idle Mode
Which of the above modes is to be determined depending on the following conditions:
1) Receive Mode
DETOTX1 < DETORX1, DETOTX2 < DETORX2, PDTX, X, PDRX : 1
2) Transmit Mode
DETOTX1 > DETORX1, DETOTX2 > DETORX2, PDTX : 1, PDRX : X
3) Slow Idle Mode
DETOTX1 > DETORX1, DETOTX2 > DETORX2, PDTX : 0, PDRX : X
DETOTX1 < DETORX1, DETOTX2 < DETORX2, PDTX : 0, PDRX : X
DETOTX1 < DETORX1, DETOTX2 > DETORX2, PDTX : 0, PDRX : X
DETOTX1 > DETORX1, DETOTX2 < DETORX2, PDTX : 0, PDRX : X
4) Fast Idle Mode
DETOTX1 > DETORX1, DETOTX2 < DETORX2, PDTX : 0, PDRX : 0
DETOTX1 < DETORX1, DETOTX2 > DETORX2, PDTX : Y, PDRX : Y
* "<" and ">" refer to voltage level : "X" refers to "It doesn't matter : "Y" is not zero
5. SWITCHING TIME
The switching time of the speaker phone is determined by the CT and RT of the outside elements.
1. Idle Mode → RX or TX Mode
ST = 4,000 X CT
2. TX or RX Mode → Fast Idle Mode
ST = 2,000 X CT
3. TX or RX Mode → Slow Idle Mode
ST = RT X CT
* CT, RT refer to the capacitor and resistor between Pin 34 and VCC.
KA8601C
APPLICATION CIRCUIT
SPEAKER PHONE WITH SPEECH NETWORK