CMLMICRO MX375J

DATA BULLETIN
Pvt SQUELCHTM CTCSS
Encoder/Decoder
MX375
Features
Applications
• PRIVATE/CLEAR CAPABILITY
• ON-CHIP TX AUDIO PRE/DEEMPHASIS
• ALTERNATIVE TO STANDARD CTCSS
“PARTY LINE”
• POWERSAVE OPTION
• MOBILE RADIOS
• COMMUNITY REPEATERS
• TELEPHONE/RADIO INTERCONNECT
SYSTEMS
TX
Filter
Output
TX
Balanced
Modulator
CLR
Input
TX Audio Output
6dB/Octave
TX Audio
Input
-6dB/Octave
RX
BIAS
RX
fEMPH
fCLK1
fCARRIER fCLK2
fEMPH
PVT
BIAS
TX
RX Audio
Input
RX Audio Output
3333Hz
XTAL
Clocks
XTAL
RX Tone Input
Reference
Hysteresis
RX Tone Decoder Output
Decode Comparator Input
Filters
RX Tone Detect Output
CTCSS
Tone Detect
3333 Hz
Load/Latch
D5 or Serial Enable 1
TX Tone
Output
D4 or Serial Enable 2
D3 or Serial Data Input
D2 or Serial Clock Input
D1 Input
D0 Input
8-Bit
Shift
Register
and
Latches
LD5-LD0
fCARRIER NoTone Output
fCLK1
VDD
fCLK2
fEMPH
RX Path
VBIAS
TX Path
Private
V
Logic
Control
RX/TX
Control
Private Enable
Push-To-Listen
SS
PTL
The MX375 is a CMOS LSI microcircuit which combines CTCSS Encode/Decode operation with voice band frequency
inversion. Frequency inversion is achieved by modulating the input audio with a 3333 Hz carrier frequency. Higher voice
band frequencies are translated downward, and lower frequencies upward, resulting in a “mirror image” voice
transmission. PvtSQUELCH combines CTCSS with inverted speech to prevent users from understanding each other’s
communications unless the transmissions are accompanied by the group’s assigned tone. Its net effect is to eliminate
casual eavesdropping and give mobile radio users a certain degree of privacy at a minimal price. Up to 38 PvtSQUELCH
user groups (one per CTCSS tone) can share a single radio channel. With PvtSQUELCH, competing businesses can
share a radio channel without compromising communications security.
Device features: 1) serial or parallel tone programming capability (serial or parallel offered on MX375J, P & LH8), 2) the
ability to operate under NOTONE conditions, 3) on-chip Tx and Rx audio filtering, 4) pin-selectable Private/Clear
operation, and 5) pre/deemphasis filters in the Tx path, for optimal recovered audio quality.
A low-cost 4 MHz crystal/clock and a single 5V supply are required for operation. The MX375 is available in the following
package styles: 28-pin PDIP (MX375P), 28-pin CDIP (MX375J) 28-pin PLCC (MX375LH8), and
24-pin PLCC (MX375LH).
© 1997 MX•COM Inc.
www.mxcom.com Tele: 800 638-5577 910 744-5050
4800 Bethania Station Road, Winston-Salem, NC 27105-1201 USA
Fax: 910 744-5054
Doc. # 20480026.007
All trademarks and service marks are held by their respective companies.
PvtSQUELCHTM CTCSS Encoder/Decoder
2
MX375
CONTENTS
Section
Page
1. Block Diagram .................................................................................................................................. 3
2. Signal List ......................................................................................................................................... 4
3. External Components ...................................................................................................................... 6
4. General Description ......................................................................................................................... 7
4.1.1 Pre- and De-emphasis .......................................................................................................................................7
4.1.2 Functions and Outputs.......................................................................................................................................7
5. Application ....................................................................................................................................... 8
5.1.1 CTCSS Programming ........................................................................................................................................8
6. Performance Specification.............................................................................................................. 9
6.1 Electrical Performance .............................................................................................................................. 9
6.2 Timing Information ................................................................................................................................... 12
6.2.1 Serial Loading ...................................................................................................................................................12
6.2.2 Parallel Loading ................................................................................................................................................13
6.3 Packaging ................................................................................................................................................ 13
MX•COM, Inc. reserves the right to change specifications at any time and without notice.
© 1997 MX•COM Inc.
www.mxcom.com Tele: 800 638-5577 910 744-5050
4800 Bethania Station Road, Winston-Salem, NC 27105-1201 USA
Fax: 910 744-5054
Doc. # 20480026.007
All trademarks and service marks are held by their respective companies.
PvtSQUELCHTM CTCSS Encoder/Decoder
3
MX375
1. Block Diagram
TX
Filter
Output
TX
Balanced
Modulator
CLR
Input
TX Audio Output
6dB/Octave
TX Audio
Input
-6dB/Octave
RX
BIAS
RX
fEMPH
fCLK1
fCARRIER
fCLK2
fEMPH
PVT
BIAS
TX
RX Audio
Input
RX Audio Output
3333Hz
XTAL
Clocks
XTAL
RX Tone Input
Reference
Hysteresis
RX Tone Decoder Output
Decode Comparator Input
Filters
RX Tone Detect Output
CTCSS
Tone Detect
3333 Hz
Load/Latch
D5 or Serial Enable 1
TX Tone
Output
D4 or Serial Enable 2
D3 or Serial Data Input
D2 or Serial Clock Input
D1 Input
D0 Input
8-Bit
Shift
Register
and
Latches
LD5-LD0
Logic
Control
RX/TX
Control
Private Enable
fCARRIER NoTone Output
fCLK1
VDD
fCLK2
fEMPH
RX Path
VBIAS
TX Path
Private
V
SS
Push-To-Listen
PTL
Figure 1: Device Block Diagram
© 1997 MX•COM Inc.
www.mxcom.com Tele: 800 638-5577 910 744-5050
4800 Bethania Station Road, Winston-Salem, NC 27105-1201 USA
Fax: 910 744-5054
Doc. # 20480026.007
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PvtSQUELCHTM CTCSS Encoder/Decoder
4
MX375
2. Signal List
Pin No.
Name
Type
Description
LH
J,P,LH8
1
28
VDD
power
5V supply pin.
2
1
XTAL/CLOCK
input
This is the input to the clock oscillator inverter. An external 4 MHz Xtal or
clock input should be applied to this pin.
3
2
XTAL
output
4
3
LOAD/ LATCH
input
This is the 4 MHz output of the clock oscillator inverter.
This input controls the eight input latches: RX/ TX , PrivateEnable , and
D0-D5, as detailed in Table 5. Alternatively, the RX/ TX and
PrivateEnable inputs can be addressed separately by setting the
Load/ Latch and Control inputs as shown in Table 5. 1 MΩ pullup.
5-7
D4-D2
input
Programming Inputs (Serial Mode Only): These are the RX /TX tone
programming and function inputs which enable the serial programming
mode. With Load/ Latch at logic “0” serial data is loaded in the following
sequence: D5, D4, D3, D2, D1, D0, RX/ TX , PrivateEnable . When these
8 bits have been clocked in on the rising clock edge, data is latched by
strobing the Load/ Latch input “0 - 1 - 0” (See Figure 5).
Pin 5 (D4) = Serial Enable2
Pin 6 (D3) = Serial Data Input
Pin 7 (D2) = Serial Clock Input
4-9
D5-D0
input
Parallel Programming Inputs: These are the RX/ TX tone programming
and function inputs which select the CTCSS tone (See Table 4).
For both Serial and Parallel Modes: In RX, a NOTONE program enables
RX Audio Output and forces the RX Tone Decode Output to a logic “0”.
In TX, a NOTONE program generates a constant VBIAS-0.7V condition at
the TX Tone Output pin. Each input has a 1 MΩ pullup resistor.
8
10
RX TONE
DECODE
output
The gated output of the decode comparator. In RX, a logic “0” indicates a
valid CTCSS tone decode condition, or the presence of NOTONE
programming. A logic “0” enables the RX audio path. In TX, this output is
held at logic “1”.
9
11
DECODE
COMPARATOR
input
The voltage level at this pin is compared internally with a fixed reference
level. A greater input level compared to the reference will result in a logic
“0” at the RX Tone Decode output. This input should be externally
connected to the RX Tone Detect output via external integration
components C10, R2, R3, and D1 (see Figure 2).
10
12
RX TONE
DETECT
output
In RX, this pin outputs a logical “1” when a valid programmed CTCSS
tone is received at the RX TONE INPUT. This input should be externally
connected to the Decode Comparator input via external integration
components C10, R2, R3, and D1 (see Figure 2).
N/A
13
NOTONE
output
This pin outputs a logic “0” when a Notone CTCSS code has been
programmed in RX. It is typically used to enable carrier squelch circuits
under Notone RX conditions.
11
14
VSS
power
The negative supply pin (ground).
12
15
TX TONE
OUTPUT
output
The buffered CTCSS sinewave tone output appears on this pin. In TX
mode, the tone frequency is selected by program code (see Table 4); if
NOTONE is programmed, the output is at Vbias-0.7V. In RX mode, the
output goes open circuit. This is an emitter follower output with an
internal 10 kΩ load.
© 1997 MX•COM Inc.
www.mxcom.com Tele: 800 638-5577 910 744-5050
4800 Bethania Station Road, Winston-Salem, NC 27105-1201 USA
Fax: 910 744-5054
Doc. # 20480026.007
All trademarks and service marks are held by their respective companies.
PvtSQUELCHTM CTCSS Encoder/Decoder
Pin No.
Name
5
MX375
Type
Description
LH
J,P,LH8
13
16
VBIAS
14
17
FILTER
OUTPUT
output
This is the output of the Input Audio Bandpass Filter. It must be A.C.
coupled to the Balanced Modulator Input via capacitor C4. See Figure 2.
15
18
BALANCED
MODULATOR
INPUT
input
This is the input to the balanced modulator. Must be A.C. coupled to the
Filter Output via capacitor C4. See Figure 2.
16
19
RX AUDIO
OUTPUT
output
Outputs the received audio from a buffered output stage and is held at
VBIAS when in TX.
17
20
TX AUDIO
OUTPUT
output
Outputs the transmitted audio in TX. In RX, this pin is held at VBIAS.
18
21
RX AUDIO
INPUT
input
The audio input for the RX mode. Input signals should be AC coupled via
external capacitor C6. See Figure 2
19
22
TX AUDIO
INPUT
input
This is the TX Audio voice input. Signals should be AC coupled via
external capacitor C11. See Figure 2
20
23
PTL
input
The “press to listen” function input. In RX mode, a logic “0” enables the
RX Audio Output directly, overriding tone squelch but not intercepting a
private conversation; in TX mode, a logic “0” reverses the phase of the TX
Tone Output for “squelch tail” reduction (see Table 5).
21
24
CONTROL
This pin is set internally to VDD/2. It must be externally decoupled using a
capacitor (C7) to VSS. See Figure 2.
This input, together with Load/ Latch , selects the operational mode of the
RX/ TX and PrivateEnable functions. See Table 5
22
25
RX/ TX
23
26
PRIVATE
ENABLE
24
27
RX TONE
INPUT
input
This input selects the RX or TX mode (RX = 1, TX = 0). This can be
loaded in Serial or Parallel modes as described in Table 5
This input selects either Private or Clear mode (Clear = 1, Private = 0),
and can be loaded by Serial or Parallel modes as described in Table 5.
This input has an internal 1 MΩ pullup resistor.
input
This is the received audio input to the on-chip CTCSS tone decoder. It
should be A.C. coupled via capacitor C5.
Note: The MX375LH package is available in serial mode only.
Table 1: Signal List
© 1997 MX•COM Inc.
www.mxcom.com Tele: 800 638-5577 910 744-5050
4800 Bethania Station Road, Winston-Salem, NC 27105-1201 USA
Fax: 910 744-5054
Doc. # 20480026.007
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PvtSQUELCHTM CTCSS Encoder/Decoder
6
MX375
3. External Components
+5V
C1 +
MX375J/P/LH8
C2
D5
D4
D3
D2
D1
D0
VSS
1
R1 2
X1
C3
3
LOAD/LATCH
4
5
6
7
8
9
10
CTCSS TONE
DECODE OUTPUT
11
C10
D1
R3 12
R2
13
NOTONE
14
XTAL
XTAL
LOAD/LATCH
D5
D4
D3
D2
D1
D0
RX DECODE
COMP IN
DETECT
NOTONE
VSS
V DD
RXTONE
PRIVEN
RX/TX
CONTROL
PTL
TXIN
RXIN
TXOUT
RXOUT
BALMOD
FILTER
BIAS
TXTONE
28
27
26
25
24
23
22
21
20
19
18
17
16
15
VDD
C5
CTCSS TONE IN (RX)
PRIVACY ENABLE
PUSH TO TALK
MODE SELECTION
PUSH TO LISTEN
C11
TX AUDIO IN
C6
RX AUDIO IN
C12
TX AUDIO OUT
C8
RX AUDIO OUT
C4
BIAS
C9
CTCSS TONE
OUTPUT (TX)
C13
C7
+
Figure 2: Recommended External Components
R1
1MΩ
±10%
C6
0.1µF
±20%
R2
560kΩ
±10%
C7
1.0µF
±20%
R3
820kΩ
±10%
C8
0.1µF
±20%
C9
0.1µF
±20%
X1
Note 1, 2
4MHz
C1
1.0µF
±20%
C10
0.1µF
±20%
C2
33pF
±20%
C11
0.1µF
±20%
C3
33pF
±20%
C12
0.1µF
±20%
C4
0.1µF
±20%
C13
0.001µF
±20%
C5
0.1µF
±20%
D1
small signal
Table 2: Recommended External Components
Recommended External Components Note:
1. For best results, a crystal oscillator design should drive the clock inverter input with signal levels of at least 40% of
VDD, peak to peak. Tuning fork crystals generally cannot meet this requirement. To obtain crystal oscillator design
assistance, consult your crystal manufacturer.
2. XTAL - At cut, fundamental, parallel resonant 20pF load capacitance, 0.05% tolerance
© 1997 MX•COM Inc.
www.mxcom.com Tele: 800 638-5577 910 744-5050
4800 Bethania Station Road, Winston-Salem, NC 27105-1201 USA
Fax: 910 744-5054
Doc. # 20480026.007
All trademarks and service marks are held by their respective companies.
PvtSQUELCHTM CTCSS Encoder/Decoder
7
MX375
4. General Description
4.1.1 Pre- and De-emphasis
Pre- and De-emphasis (6dB/octave) filters are included on-chip in the transmit path, so that the use of this device will
produce natural sounding audio (clear or private modes) when installed in modern radio communication transceivers, with
or without existing audio processing circuitry. The recommended layout is shown in block form below.
Clear
To Transmitter
Stages
Band Pass
Filter
Pre-emphasis
Amplifier
Band Pass
Filter
De-emphasis
Pre-emphasis
Modulator
Clear
From Receiver
Stages
Band Pass
Filter
Demodulator
Band Pass
Filter
De-emphasis
Amplifier
Figure 3: Transmit and Receive Paths
4.1.2 Functions and Outputs
D0-D5
Notone
RX/TX
PRIVATE
ENABLE
PTL
RX TONE
DETECT
RX TONE
DECODER
TONE
OUTPUT
TONE
PHASE
TX
PATH
RX
PATH
PATH
STATE
Tone
1
0
0
1
0
1
Tone
1
0
0
0
0
1
Notone
0
0
0
X
0
Tone
1
1
0
1
Tone
1
1
0
0
TONE
YES
0°
OPEN
BIAS
INV
TX, TONE
YES
180°
OPEN
BIAS
INV
TX, TONE REV
1
BIAS
X
OPEN
BIAS
CLR
TX, NOTONE
0
1
BIAS
X
BIAS
BIAS
X
INCOMPATIBLE
0
1
BIAS
X
BIAS
OPEN
CLR
INCOMPATIBLE
Tone
1
1
0
X
1
0
BIAS
X
BIAS
OPEN
INV
COMPATIBLE
Notone
0
1
0
X
X
0
BIAS
X
BIAS
OPEN
CLR
RX, NOTONE
Tone
1
0
1
1
0
1
YES
0°
OPEN
BIAS
CLR
TX, TONE
Tone
1
0
1
0
0
1
YES
180°
OPEN
BIAS
CLR
TX, TONE REV
Notone
0
0
1
X
0
1
BIAS
X
OPEN
BIAS
CLR
TX, NOTONE
Tone
1
1
1
1
0
1
BIAS
X
BIAS
BIAS
X
INCOMPATIBLE
Tone
1
1
1
0
0
1
BIAS
X
BIAS
OPEN
CLR
INCOMPATIBLE
Tone
1
1
1
X
1
0
BIAS
X
BIAS
OPEN
CLR
COMPATIBLE
Notone
0
1
1
X
X
0
BIAS
X
BIAS
OPEN
CLR
RX, NOTONE
Table 3: Functions and Outputs
Note:
1. Algebraic functions:
RX Path On = RX × (PTL + RX Tone Decoder)
Clear Path = Notone + Private Enable + (PTL × RX × RX Tone Decoder)
Notone (D0 - D5) = 000011
Carrier Frequency = 3333Hz During inverted Path (TX or RX)
2. The Pre- and De-emphasis circuits remain in the transmit path in both the Clear and Invert Modes.
3. Power remains applied to the CTCSS tone decoder at all times.
4. During clear operation the carrier frequency is turned off to reduce spurious emissions.
© 1997 MX•COM Inc.
www.mxcom.com Tele: 800 638-5577 910 744-5050
4800 Bethania Station Road, Winston-Salem, NC 27105-1201 USA
Fax: 910 744-5054
Doc. # 20480026.007
All trademarks and service marks are held by their respective companies.
PvtSQUELCHTM CTCSS Encoder/Decoder
8
MX375
5. Application
5.1.1 CTCSS Programming
Nominal
Frequency(Hz)
∆ F0 (%)
D5
D4
D3
D2
D1
D0
67.05
+0.07
1
1
1
1
1
1
Frequency(Hz)
67.0
Program Inputs
71.9
71.9
0
0
1
1
1
1
1
74.4
74.35
-0.07
1
1
1
1
1
0
77.0
76.96
-0.5
0
0
1
1
1
1
79.7
79.77
+0.09
1
1
1
1
0
1
82.5
82.59
+0.1
0
1
1
1
1
0
85.4
85.38
-0.2
1
1
1
1
0
0
88.5
88.61
+0.13
0
0
1
1
1
0
91.5
91.58
+0.09
1
1
1
0
1
1
94.8
94.76
-0.04
0
1
1
1
0
1
97.4
97.29
-0.11
1
1
1
0
1
0
100.0
99.96
-0.04
0
0
1
1
0
1
103.5
103.43
-0.07
0
1
1
1
0
0
107.2
107.15
-0.05
0
0
1
1
0
0
110.9
110.77
-0.12
0
1
1
0
1
1
114.8
114.64
-0.14
0
0
1
0
1
1
118.8
118.8
0
0
1
1
0
1
0
123.0
122.8
-0.17
0
0
1
0
1
0
127.3
127.08
-0.17
0
1
1
0
0
1
131.8
131.67
-0.10
0
0
1
0
0
1
136.5
136.61
+0.08
0
1
1
0
0
0
141.3
141.32
+0.02
0
0
1
0
0
0
146.2
146.37
+0.12
0
1
0
1
1
1
151.4
151.09
-0.2
0
0
0
1
1
1
156.7
156.88
+0.11
0
1
0
1
1
0
162.2
162.31
+0.07
0
0
0
1
1
0
167.9
168.14
+0.14
0
1
0
1
0
1
173.8
173.48
-0.19
0
0
0
1
0
1
179.9
180.15
+0.14
0
1
0
1
0
0
186.2
186.29
+0.05
0
0
0
1
0
0
192.8
192.86
+0.03
0
1
0
0
1
1
203.5
203.65
+0.07
0
0
0
0
1
1
210.7
210.17
-0.25
0
1
0
0
1
0
218.1
218.58
+0.22
0
0
0
0
1
0
225.7
226.12
+0.18
0
1
0
0
0
1
233.6
234.19
+0.25
0
0
0
0
0
1
241.8
241.08
-0.30
0
1
0
0
0
0
250.3
250.28
-0.01
0
0
0
0
0
0
1
1
0
0
0
0
Notone
Table 4: CTCSS Programming
© 1997 MX•COM Inc.
www.mxcom.com Tele: 800 638-5577 910 744-5050
4800 Bethania Station Road, Winston-Salem, NC 27105-1201 USA
Fax: 910 744-5054
Doc. # 20480026.007
All trademarks and service marks are held by their respective companies.
PvtSQUELCHTM CTCSS Encoder/Decoder
9
MX375
(A) Explanation of Load/Latch function in Serial and Parallel Modes
Load Configuration
Result
Load/ Latch
Parallel
1
Parallel
1-0
Transparent, the data acts directly
Latches present data in
Parallel
0
No further changes except to allow serial mode selection
Serial (data loading)
0
No change while serial data train is loaded
Serial (data loaded)
0-1-0
Loaded serial data is latched
(B) Explanation of Control Input
Load Configuration
Load/ Latch
Control
RX/ TX , Private Enable
Parallel
0
0
Latched
Parallel
1
0
Transparent
Parallel
X
1
Transparent
Serial
0-1-0
0
Serial Load
Serial
X
1
Transparent
Table 5: Load/ Latch and Control Input Function
Notes:
1. “0 - 1 - 0” is a strobe pulse as shown in Figure 4 and Figure 5.
2. “X” denotes any logical state.
6. Performance Specification
6.1 Electrical Performance
Absolute Maximum Ratings
Exceeding these maximum ratings can result in damage to the device.
General
Min.
Supply Voltage
Input Voltage at any pin
Typ.
Max.
Units
-0.3
7.0
V
-0.3
(VDD + 0.3)
V
VDD
-30
30
mA
VSS
-30
30
mA
Any other pin
-20
20
mA
800
mW
10
mW/°C above 25°C
Current
J / P / LH / LH8 Packages
Total Device Dissipation at TAMB 25°C
Derating above 25°C
Operating Temperature
-40°
85°
C
Storage Temperature
-55°
125°
C
Table 6: Absolute Maximum Ratings
© 1997 MX•COM Inc.
www.mxcom.com Tele: 800 638-5577 910 744-5050
4800 Bethania Station Road, Winston-Salem, NC 27105-1201 USA
Fax: 910 744-5054
Doc. # 20480026.007
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PvtSQUELCHTM CTCSS Encoder/Decoder
10
MX375
Operating Limits
Correct operation of the device outside these limits is not implied.
Notes
Min.
Typ.
Max.
Units
Supply (VDD-VSS)
4.5
5.0
5.5
V
Operating Temperature
-40
85
°C
Xtal/Clock Frequency
4.0
MHz
Table 7: Operating Limits
Operating Characteristics
For the following conditions unless otherwise specified:
VDD = 5.0V, TAMB = 25°C, XTAL = 4.0MHz, Audio level )dB ref. = 300mVRMS, Composite input signal = 0dB,
1 kHz tone in, -12dB (6kHz band limited) Gaussian white noise with a -20dB CTCSS tone.
Notes
Min.
Typ.
Max
Units
4.5
5.0
5.5
V
TX (Private)
15.0
mA
TX (Operating)
12.0
mA
RX (Operating)
7.0
mA
Static Values
Supply Voltage
Supply Current
Analog Input Impedance
0.5
MΩ
Analog Output Impedance
0.5
kΩ
Tone Input Impedance
0.5
MΩ
Input Logic “1”
3.5
V
Input Logic “0”
1.5
Output Logic “1” (I=-0.1mA)
4.0
V
V
Output Logic “0” (I=-0.1mA)
1.0
V
Dynamic Values
Decoder
Input Signal Level
1,4
-20
dB
Response Time
1,4,6
250
ms
Deresponse Time
1,4,6
250
ms
±3.0
%f0
3.0
dB
0.3
%f0
5.0
%
5.0
mA
1.0
dB
Selectivity
4
±0.5
Encoder
Tone Output Level (775mVRMS ref.)
-3.0
Tone Frequency Accuracy
-0.3
Tone Harmonic Distortion
0
2.0
Tone Output Load Current
2
Output Level Variation between Tones
9
-1.0
Risetime (to 90% nominal level)
(f0>100 Hz)
5
15
ms
(f0<100 Hz)
5
45
ms
© 1997 MX•COM Inc.
www.mxcom.com Tele: 800 638-5577 910 744-5050
4800 Bethania Station Road, Winston-Salem, NC 27105-1201 USA
Fax: 910 744-5054
Doc. # 20480026.007
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PvtSQUELCHTM CTCSS Encoder/Decoder
11
MX375
Notes
Min.
Typ.
Max
Units
5
%
RX Clear
Total Harmonic Distortion
3
2
Output Noise Level
7
-43
Passband Gain (300-3033Hz)
3
Passband Ripple (300-3033Hz)
3
-1
0
dB
1
dB
3
dB
Audio Stopband Attenuation
(fIN>3333Hz)
8
-20
dB
(fIN>3633Hz)
8
-45
dB
-42
dB
(fIN<250Hz)
RX Invert
Total Harmonic Distortion
3,8
4
Baseband Breakthrough
3
-40
dB
Carrier Breakthrough
10
%
-40
dB
7,8
-37
dB
3
-
(fIN>3333Hz)
8
-50
dB
(fIN>3633Hz)
8
-60
dB
-60
dB
Output Noise Level
Passband Ripple (300-3000Hz)
4
dB
Audio Stopband Attenuation
(fIN<250Hz)
TX Clear
Total Harmonic Distortion
3
3
5
%
Output Noise Level
7
-43
dB
Passband Gain (300-3033Hz)
3
0
dB
Passband Ripple (300-3033Hz)
3
3
dB
Audio Stopband Attenuation
(fIN>3333Hz)
8
-20
dB
(fIN>3633Hz)
8
-45
dB
-42
dB
(fIN<250Hz)
TX Invert
Total Harmonic Distortion
3,8
4
Baseband Breakthrough
Carrier Breakthrough
Output Noise Level
7,8
Passband Ripple (300-3033Hz)
3,8
10
%
-40
dB
-40
dB
-37
dB
4
dB
Audio Stopband Attenuation
(fIN>3333Hz)
8
-50
dB
(fIN>3633Hz)
8
-60
dB
(fIN<250Hz)
8
-60
dB
Table 8: Operating Characteristics
© 1997 MX•COM Inc.
www.mxcom.com Tele: 800 638-5577 910 744-5050
4800 Bethania Station Road, Winston-Salem, NC 27105-1201 USA
Fax: 910 744-5054
Doc. # 20480026.007
All trademarks and service marks are held by their respective companies.
PvtSQUELCHTM CTCSS Encoder/Decoder
12
MX375
Operating Characteristics Notes:
1. These values are obtained using the external integrating components given in Figure 2.
2. An emitter follower output
3. With an input signal of 1 kHz @ 0dB.
4. Under Composite Signal test conditions.
5. Any programmed tone with RL=600 Ω, CL=15pF, including any response to a phase reversal instruction.
6. f0 > 100 Hz, (for 100Hz > f0 > 67Hz: t = [100/f0(Hz)] x 250ms).
7. Input ac short-circuit, audio path enabled.
8. Due to frequency inversion, these figures reflect the difference from the ideal response.
9. Reference 156.7 Hz (MX175 and MX275).
6.2 Timing Information
6.2.1 Serial Loading
Min.
Typ.
Max.
Unit
Serial Mode Enable Set Up Time
(tSMS)
250
-
-
ns
Clock “High” Pulse Width (tPWH)
250
-
-
ns
Clock “Low” Pulse Width (tPWL)
250
-
-
ns
Data Set Up Time (tDS)
150
-
-
ns
Data Hold Time (tDH)
50
-
-
ns
Load/Latch Set Up Time (tLL)
250
-
-
ns
Load/Latch Pulse Width (tLLW)
150
-
-
ns
Table 9: Serial Loading Timing Information
D4
SERIAL MODE
ENABLE
D5
t SMS
t PWH
t PWL
SERIAL CLOCK
t DH
t DS
SERIAL DATA
INPUT
t LL
t LLW
LOAD/LATCH
Figure 4: Serial Loading Timing
© 1997 MX•COM Inc.
www.mxcom.com Tele: 800 638-5577 910 744-5050
4800 Bethania Station Road, Winston-Salem, NC 27105-1201 USA
Fax: 910 744-5054
Doc. # 20480026.007
All trademarks and service marks are held by their respective companies.
PvtSQUELCHTM CTCSS Encoder/Decoder
13
MX375
6.2.2 Parallel Loading
Min.
Typ.
Max.
Unit
Data Valid Time (tVP)
200
ns
Load Time (tL)
150
ns
Fall Time (tF)
50
Data Hold Time (tH)
50
ns
ns
Table 10: Parallel Loading Timing Information
tVP
DATA INPUTS
D0 - D5
RX/TX
PRIVATE ENABLE
tL
tF
LOAD/LATCH
tH
LOAD DATA
DATA LATCHED
Figure 5: Parallel Load Timing
6.3 Packaging
E
B
C
Package Tolerances
K
DIM.
A
B
C
D
E
F
G
H
J
K
P
T
W
Y
Y
DA
W
J
W
T
PIN 1
H
P
G
MIN.
TYP.
MAX.
0.380 (9.61)
0.409 (10.40)
0.380 (9.61)
0.409 (10.40)
0.128 (3.25)
0.146 (3.70)
0.417 (10.60)
0.435 (11.05)
0.417 (10.60)
0.435 (11.05)
0.250 (6.35)
0.250 (6.35)
0.023 (0.58)
0.018 (0.45)
0.022 (0.55)
0.047 (1.19)
0.048 (1.22)
0.049 (1.24)
0.051 (1.30)
0.006 (0.152)
0.009 (0.22)
45°
30°
6°
NOTE : All dimensions in inches (mm.)
Angles are in degrees
F
Figure 6: 24-pin PLCC Mechanical Outline: Order as part no. MX375LH
© 1997 MX•COM Inc.
www.mxcom.com Tele: 800 638-5577 910 744-5050
4800 Bethania Station Road, Winston-Salem, NC 27105-1201 USA
Fax: 910 744-5054
Doc. # 20480026.007
All trademarks and service marks are held by their respective companies.
PvtSQUELCHTM CTCSS Encoder/Decoder
14
MX375
D
B
A
pin 1
Package Tolerances
G
F
E
C
H
DIM.
MIN.
MAX.
A
B
C
D
E
F
G
H
J
.450 (11.43)
.485 (12.32)
.453 (11.51)
.495 (12.57)
.045x45
.165 (4.20)
.026 (0.66)
.017 (0.43)
.410 (10.41)
.050 (1.27)
.070 (1.78)
typical
.180 (4.57)
.030 (0.76)
.021 (0.53)
.430 (10.92)
typical
.085 (2.16)
NOTE : All dimensions in inches (mm.)
Angles are in degrees
J
Figure 7: 28-pin PLCC Mechanical Outline: Order as part no. MX375LH8
A
Package Tolerances
B
E
E1
Y
T
PIN1
K
H
L
C
J
J1
P
DIM.
A
B
C
E
E1
H
J
J1
K
L
P
T
Y
MIN.
TYP.
MAX.
1.440 (36.44)
1.47 (37.20)
0.530 (13.41)
0.555 (14.04)
0.160 (4.05)
0.220 (5.59)
0.600 (15.24)
0.670 (17.02)
0.590 (14.99)
0.625 (15.88)
0.015 (0.38)
0.045 (1.14)
0.013 (0.33)
0.021 (0.53)
0.060 (1.52)
0.066 (1.67)
0.074 (1.88)
0.125 (3.16)
0.160 (4.05)
0.100 (2.54)
0.010 (0.25)
7°
NOTE : All dimensions in inches (mm.)
Angles are in degrees
Figure 8: 28-pin PDIP Mechanical Outline: Order as part no. MX375P
© 1997 MX•COM Inc.
www.mxcom.com Tele: 800 638-5577 910 744-5050
4800 Bethania Station Road, Winston-Salem, NC 27105-1201 USA
Fax: 910 744-5054
Doc. # 20480026.007
All trademarks and service marks are held by their respective companies.
PvtSQUELCHTM CTCSS Encoder/Decoder
15
MX375
Package Tolerances
A
DIM.
B
E
E1
T
PIN1
K
K1 C
H
L
J
J1
P
A
B
C
E
E1
F
H
J
J1
K
K1
L
P
T
MIN.
TYP.
MAX.
1.440 (36.58)
1.460 (37.08)
0.510 (12.94)
0.530 (13.45)
0.165 (4.19)
0.230 (5.84)
0.640 (16.26)
0.715 (18.14)
0.608 (15.43)
0.618 (15.70)
1.300 (33.02)
0.050 (1.27)
0.015 (0.38)
0.018 (0.46)
0.055 (1.39)
0.050 (1.27)
0.080 (2.03)
0.075 (1.91)
0.080 (2.03)
0.115 (2.92)
0.171 (4.34)
0.100 (2.54)
0.0090 (0.228)
0.0102 (0.259)
NOTE : All dimensions in inches (mm.)
Angles are in degrees
F
Figure 9: 28-pin CDIP Mechanical Outline: Order as part no. MX375J
© 1997 MX•COM Inc.
www.mxcom.com Tele: 800 638-5577 910 744-5050
4800 Bethania Station Road, Winston-Salem, NC 27105-1201 USA
Fax: 910 744-5054
Doc. # 20480026.007
All trademarks and service marks are held by their respective companies.
CML Microcircuits
COMMUNICATION SEMICONDUCTORS
CML Product Data
In the process of creating a more global image, the three standard product semiconductor
companies of CML Microsystems Plc (Consumer Microcircuits Limited (UK), MX-COM, Inc
(USA) and CML Microcircuits (Singapore) Pte Ltd) have undergone name changes and, whilst
maintaining their separate new names (CML Microcircuits (UK) Ltd, CML Microcircuits (USA)
Inc and CML Microcircuits (Singapore) Pte Ltd), now operate under the single title CML
Microcircuits.
These companies are all 100% owned operating companies of the CML Microsystems Plc
Group and these changes are purely changes of name and do not change any underlying legal
entities and hence will have no effect on any agreements or contacts currently in force.
CML Microcircuits Product Prefix Codes
Until the latter part of 1996, the differentiator between products manufactured and sold from
MXCOM, Inc. and Consumer Microcircuits Limited were denoted by the prefixes MX and FX
respectively. These products use the same silicon etc. and today still carry the same prefixes.
In the latter part of 1996, both companies adopted the common prefix: CMX.
This notification is relevant product information to which it is attached.
CML Microcircuits (USA) [formerly MX-COM, Inc.] Product Textual Marking
On CML Microcircuits (USA) products, the ‘MX-COM’ textual logo is being replaced by a ‘CML’
textual logo.
Company contact information is as below:
CML Microcircuits
(UK)Ltd
CML Microcircuits
(USA) Inc.
CML Microcircuits
(Singapore)PteLtd
COMMUNICATION SEMICONDUCTORS
COMMUNICATION SEMICONDUCTORS
COMMUNICATION SEMICONDUCTORS
Oval Park, Langford, Maldon,
Essex, CM9 6WG, England
Tel: +44 (0)1621 875500
Fax: +44 (0)1621 875600
[email protected]
www.cmlmicro.com
4800 Bethania Station Road,
Winston-Salem, NC 27105, USA
Tel: +1 336 744 5050,
0800 638 5577
Fax: +1 336 744 5054
[email protected]
www.cmlmicro.com
No 2 Kallang Pudding Road, 09-05/
06 Mactech Industrial Building,
Singapore 349307
Tel: +65 7450426
Fax: +65 7452917
[email protected]
www.cmlmicro.com
D/CML (D)/2 May 2002