Datasheet CMX631AD4, CMX631AP3, CMX631AD5 Datasheet (MX COM Inc)

DATA BULLETIN

CMX631A

•COM Inc. www.mxcom.com Tele: 800 638-5577 336 744-5050 Fax: 336 744-5054 Doc. # 20480177.004

4800 Bethania Station Road, Winston-Salem, NC 27105-1201 USA All trademarks and service marks are held by their respective companies.

Low Voltage

SPM Detector

PRELIMINARY INFORMATION

Features Applications

•

Detects 12kHz or 16kHz SPM Frequencies

•

Tone Follower and Packet Mode Outputs

•

High Speech-Band Rejection Properties

•

Low Power Operation (3.0V < 0.8mA)

•

Call Charge Applications on PABX Line Cards

•

Complex and/or Simple telephone Systems

•

Remote Telephone/Payphones

+

-

1

32

PERIOD

MEASURE

TONE

FOLLOWER

LOGIC

PACKET

TONE

LOGIC

DIVIDER

SIGNAL IN (-)

AMP OUT

XTAL/CLOCK

SYSTEM (12kHz/16kHz)

SYSTEM

CLOCK IN

CLOCK OUT

TONE FOLLOWER

OUTPUT

V

SS

V

DD

V

BIAS

P ACKET MODE

OUTPUT

SIGNAL IN (+)

LEVEL DETECTOR

+20dB

12kHz/16kHz

XTAL

CLOCK

DIVIDERS

INPUT AM P

XTAL/CLOCK

OSCILLATOR

The CMX631A is a low-power, system-selectable Subscriber Pulse Metering (SPM) detector that indicates the presence of both 12kHz or 16kHz telephone call-charge frequencies on a telephone line.

Deriving its input directly from the telephone line, input amplitude/sensitivities are component adjustable to the user's national ‘Must/Must-Not Decode’ specifications via an on-chip input amplifier. The 12kHz and 16kHz frequency limits are accurately defined by the use of an external 3.579545MHz telephone-system Xtal or clock-pulse input.

The CMX631A demonstrates exceptional 12kHz and 16kHz performance in the presence of both voice and noise. This device may operate from a single or differential analog signal input, from which two individual logic outputs will be produced; a Tone Follower Output or a Packet Mode Output.

This system (12kHz/16kHz) selectable integrated circuit, requires a 2.7V to 5.5V power supply, which may be line-powered, is available in the following packages: 24-pin SSOP (CMX631AD5), 16-pin SOIC (CMX631AD4), and 16-pin PDIP (CMX631AP3). Additional package styles may be available to meet specific design requirements.

Low Voltage SPM Detector 2 CMX631A PRELIMINARY INFORMATION

4800 Bethania Station Road, Winston-Salem, NC 27105-1201 USA All trademarks and service marks are held by their respective companies.

CONTENTS

Section Page

1 Block Diagram................................................................................................................3

2 Signal List.......................................................................................................................4

3 External Components....................................................................................................5

4 General Description.......................................................................................................6

4.1 Tone Follower Mode............................................................................................................ 6

4.2 Packet Mode........................................................................................................................ 6

4.3 Sensitivity Setting ................................................................................................................ 6

4.3.1 Input Gain Calculation............................................................................................................6

4.3.2 Input Gain Components .........................................................................................................8

4.4 ‘WILL’/’WILL-NOT’ Detect Frequencies............................................................................... 8

5 Applications ...................................................................................................................8

5.1 Input Configurations ............................................................................................................ 8

5.1.1 Protection Against High Voltages...........................................................................................8

5.1.2 Aliasing...................................................................................................................................9

6 Performance Specification............................................................................................9

6.1 Electrical Specifications....................................................................................................... 9

6.1.1 Absolute Maximum Ratings....................................................................................................9

6.1.2 Operating Limits...................................................................................................................10

6.1.3 Operating Characteristics.....................................................................................................10

6.2 Packages........................................................................................................................... 11

MX-COM, Inc. reserves the right to change specifications at any time and without notice.

Low Voltage SPM Detector 3 CMX631A PRELIMINARY INFORMATION

4800 Bethania Station Road, Winston-Salem, NC 27105-1201 USA All trademarks and service marks are held by their respective companies.

1 Block Diagram

+

-

1

32

PERIOD

MEASURE

TONE

FOLLOWER

LOGIC

PACKET

TONE

LOGIC

DIVIDER

SIGNAL IN (-)

AMP OUT

XTAL/CLOCK

SYSTEM (12kHz/16kHz)

SYSTEM

CLOCK IN

CLOCK OUT

TONE FOLLOWER

OUTPUT

V

SS

V

DD

V

BIAS

P ACKET MODE

OUTPUT

SIGNAL IN (+)

LEVEL DETECTOR

+20dB

12kHz/16kHz

XTAL

CLOCK

DIVIDERS

INPUT AM P

XTAL/CLOCK OSCILLATOR

Figure 1: Block Diagram

Low Voltage SPM Detector 4 CMX631A PRELIMINARY INFORMATION

4800 Bethania Station Road, Winston-Salem, NC 27105-1201 USA All trademarks and service marks are held by their respective companies.

2 Signal List

Packages Signal

D5 D4/P3 Name Type

Description

1 1 Xtal/Clock input The input to the on-chip clock oscillator; for use with a

3.579545MHz Xtal in conjunction with the Xtal output; circuit components are on-chip. When using a Xtal input, the Clock Out pin should be connected directly to the Clock In pin. If a clock pulse input is used at the Clock In pin, this (Xtal/Clock) pin must be connected directly to V

DD

See Figure 2 and

Section 3.

42

XTAL

output The output of the on-chip clock oscillator inverter.

5 3 Clock Out output The buffered output of the on-chip-clock oscillator inverter. If a

Xtal input is used, this output should be connected directly to the Clock In pin.

6 4 Clock In input The 3.579545MHz clock pulse input to the internal clock

dividers. If an externally generated clock pulse is used, the Xtal/Clock input pin should be connected to V

DD

. Reference

Section 3.

87V

BIAS

power The output of the on-chip analog bias circuitry. Held internally

at V

DD

/2, this pin should be bypassed to VSS. See Figure 2.

12 8 V

SS

power Negative supply (GND).

13 9 Signal In + input The positive input to the input gain adjusting signal amplifier.

Reference Section 4.3 and 4.4.

17 10 Signal In - input The negative input to the input gain adjusting signal amplifier.

Reference Section 4.3 and 4.4.

18 11 Amp Out input The output of the input gain adjusting signal amplifier.

Reference Section 4.3 and 4.4.

19 13 Tone

Follower

Mode

output This output provides a logic 0 for the period of a detected tone

and a logic 1 for a NOTONE detection. See Section 4.1 and Figure 3.

20 14 Packet Mode output This output provides a logic 0 for a detected tone and a logic 1

for NOTONE detection and will ignore a small fluctuation or fade during the tone signal. See Section 4.2 and Figure 3.

21 15 System input This logic input selects the device operation to either 12kHz

(logic 1) or 16kHz (logic 0) SPM systems. This input has an internal 1MΩ pull-up resistor (12kHz).

24 16 V

DD

power Positive supply. A single, stable power supply is required.

Critical levels and voltages within the CMX631A are dependent upon this supply. This pin should be bypassed to V

SS

by a

capacitor mounted close to the pin. Note: If this device is line powered, the resulting power supply must be stable. See Section 5.1.1.

2, 3, 7,

9, 10, 11, 14, 15, 16,

22, 23

5,6,12 N/C No internal connection; leave open circuit.

Table 1: Signal List

Low Voltage SPM Detector 5 CMX631A PRELIMINARY INFORMATION

4800 Bethania Station Road, Winston-Salem, NC 27105-1201 USA All trademarks and service marks are held by their respective companies.

3 External Components

V

DD

C1

C2

C4

C3

R4

R3

R2

R1

V

SS

V

BIAS

1 2

3 4

5 6 7 8

16 15

14 13

12

11

10

9

TONE FOLLOWER OUTPUT

PACKET MODE OUTPUT

SYSTEM

CLOCK IN

SIGNAL IN (+)

SIGNAL IN (-)

AMP OUT

X1

XTAL/CLOCK

CLOCK OUT

XTAL

CMX631A

D4/P3

V

DD

Figure 2: Recommended External Components

R1 Note 1 R

FEEDBACK

C1 1.0µF ±20%

R2 Note 1 R

IN(-)

C2 1.0µF ±20%

R3 Note 1 R

IN(+)

C3 C

IN(-)

R4 Note 1 R

BIAS

C4 C

IN(+)

X1 Note 2, 3, 4 3.579545MHz

Table 2: Recommended External Components

Recommended External Component Notes:

1. When calculating input gain components, for correct operation R1 and R4 should always be ≥ 33kΩ.

2. For best results, a crystal oscillator design should drive the clock inverter input with signal levels of at least 40% of V

DD

, peak to peak. Tuning fork crystals generally cannot meet this requirement. To

obtain crystal oscillator design assistance, consult your crystal manufacturer.

3. The on-chip crystal circuitry includes a feedback resistor (nominally 2MΩ) between pins 1 and 2 and load capacitors on pins 1 and 2 (nominally 10pF each, excluding package and board parasitics).

4. When using an external clock input, X1 should be removed, Pin 1 (Xtal/Clock) should be tied to VDD, the Clock In and Clock Out jumper should be removed, and the external clock signal applied to Clock

In.

Low Voltage SPM Detector 6 CMX631A PRELIMINARY INFORMATION

4800 Bethania Station Road, Winston-Salem, NC 27105-1201 USA All trademarks and service marks are held by their respective companies.

4 General Description

4.1 Tone Follower Mode

The Tone Follower Output Mode will respond and/or de-respond when a signal is detected or a NOTONE, by providing a Logic level output. When a signal has been detected, a Logic 0 is provided at the output for the duration of the valid signal. When a NOTONE or invalid decode is detected a Logic 1 is provided at the output until a valid signal is available. See Figure 3.

4.2 Packet Mode

The Packet (Cumulative Tone) Mode Output will respond and/or de-respond after a cumulative 40ms of good tone (or NOTONE) in any 48ms period by providing a Logic level output. See Figure 3.

This process does ignore the small fluctuations or fades of a valid frequency input. During a 40ms toneburst, no tone interruption (small fluctuation or fade) is allowed during this period for the signal to be considered valid. If a 45ms toneburst occurs, then a 2ms interruption is allowed, and the signal is still considered valid. For NOTONE, there must be 40ms of continuous no tone or for a 45ms period, there may be 2ms of tone and the NOTONE still be valid. For a valid detect of tone the output provides a Logic 0. For the valid detect of NOTONE, the output provides a Logic 1.

This output is available for µProcessor ‘Wake-Up’, Minimum Tone detection, NOTONE indication, or transient avoidance.

SIGNAL INPUT

RESPONSE DELAY

TONE FOLLOWER OUTPUT

P ACKET MODE OUTPUT

DERESPONSE DELAY

SIGNAL INPUT

P ACKET MODE OUTPUT

TONE FOLLOWER OUTPUT

RESPONSE DELAY

De-response

Response

DERESPONSE DELAY

Figure 3: Tone Follower and Packet Mode Outputs

4.3 Sensitivity Setting

The CMX631A input sensitivity can be accurately adjusted and set to support many national 12kHz and 16kHz SPM specifications.

4.3.1 Input Gain Calculation

The input amplifier, with external circuitry, is used to set the sensitivity of the CMX631A to conform to the user's national level specification with regard to ‘Must’ and ‘Must-Not’ decode signal levels.

With reference to the graphs in Figure 4 and Figure 5, the following steps will assist in the determination of the required gain/attenuation.

1. Draw two horizontal lines from the Y-axis [Signal Level (dB)] in Figure 4 and Figure 5. The upper line represents the required ‘Must’ decode level. The lower line represents the required ‘Must-Not’ decode level

Low Voltage SPM Detector 7 CMX631A PRELIMINARY INFORMATION

4800 Bethania Station Road, Winston-Salem, NC 27105-1201 USA All trademarks and service marks are held by their respective companies.

2. Mark the intersection of the upper horizontal line and the upper sloping line; drop a vertical line from this point to the X-axis [Amplifier Gain (dB)]. The point where the vertical line meets the X-axis indicates the minimum Input Amp gain required for reliable decoding of valid signals.

3. Mark the intersection of the lower horizontal line and the lower sloping line; drop a vertical line from this point to the X-axis. The point where the vertical line meets the X-axis will indicate the maximum allowable Input Amp gain. Input signals at or below the ‘Must-Not’ decode level will not be detected as long as the amplifier gain is no higher than this level.

-5 0

-4 0

-3 0

-2 0

-1 0

-3 0 -2 0 -1 0 0 10 20 30

MUST DECODE LEVEL

MUST NOT DECODE LEVEL

MAXIMUMAMPLIFIER GAINMINIMUM AMPLIFIER GAIN

AMPLIFIER GAIN (dB) V = 3.0V (±0.1) T = -40°C to 85°C

DD AMB

SIGNAL LEVEL (dB) 0dB ref: 775mV

RMS

Figure 4: Input Gain Calculation Graph for VDD = 3.0V

-50

-45

-40

-35

-30

-25

-20

-15

-10

-25 -20 -15 -10

-5

0

5

10 15 20 25

MUST DECODE LEVEL

MUST NOT DECODE LEVEL

AMPLIFIER GAIN (dB) V = 5.0 (±0.5) TEMP = -40°C to 85°C

DD

SIGNAL LEVEL (dB) 0dB ref: 775mV

RMS

MINIMUM AM P L IF IE R GAIN MAXIMUM AMPLIFIER G AIN

Figure 5: Input Gain Calculation Graph for VDD = 5.0V

Low Voltage SPM Detector 8 CMX631A PRELIMINARY INFORMATION

4800 Bethania Station Road, Winston-Salem, NC 27105-1201 USA All trademarks and service marks are held by their respective companies.

4.3.2 Input Gain Components

Reference the gain components found in Table 2 and Figure 2. The user should calculate and select external components (R1/R3/C3 and R2/R4/C4) to provide amplifier gain within the limits obtained in Section 4.3.1.

Component tolerances should not move the gain-figure outside these limits. The graphs in Figure 4 and Figure 5 are for the calculation of input gain components for a CMX631A using a V

DD

of 3.0 (±0.1) or VDD of

5.0 (±0.5).

4.4 ‘WILL’/’WILL-NOT’ Detect Frequencies

16.00kHz

15.76kHz

15.36kHz

F-4%

0

F+4%

0

F - 1.5%

0

F + 1.5%

0F0

16.24kHz

16.64kHz

12.00kHz

11.82kHz

11.52kHz

F-4%

0

F+4%

0

F - 1.5%

0

F + 1.5%

0F0

12.18kHz

12.48kHz

WILL-NOT DETECT

FREQUENCIES

WILL-NOT DETECT

FREQUENCIES

WILL-NOT DETECT

FREQUENCIES

WILL-NOT DETECT

FREQUENCIES

WILL DETECT

FREQUENCIES

WILL-DETECT

FREQUENCIES

Figure 6: ‘WILL’/’WILL-NOT’ Detect Frequencies

5 Applications

5.1 Input Configurations

+

-

INPUT AMP

V

BIAS

+

-

Tip (a)

Ring (b)

INPUT AMP

CMX631A

V

BIAS

Differential Input

Common Mode Input

CMX631A

Figure 7: Input Configurations

5.1.1 Protection Against High Voltages

Telephone systems may have high DC and AC voltages present on the line. If the CMX631A is a part of host equipment that has its own signal input protection circuitry, there will be no need for further protection as long as the voltage on any pin is limited to within V

DD

+0.3V and VSS -0.3V.

If the host system does not have input protection, or there are signals present outside the device's specified limits, the CMX631A will require protection diodes at its signal inputs (+ and -). The breakdown voltage of capacitors and the peak inverse voltage of the diodes must be sufficient to withstand the sum of the DC voltages plus all expected signal peaks.

Low Voltage SPM Detector 9 CMX631A PRELIMINARY INFORMATION

4800 Bethania Station Road, Winston-Salem, NC 27105-1201 USA All trademarks and service marks are held by their respective companies.

5.1.2 Aliasing

Due to the sampling nature of switched-capacitor filters used in the CMX631A, high frequency noise or unwanted signals can alias into the passband, disrupting detection. External components must be chosen carefully to avoid alias effects.

Possible Alias Frequencies:

12kHz Mode = 52kHz 16kHz Mode = 69kHz

If other filtering in the system has not attenuated these alias frequencies, capacitors should be employed across resistors R1 and R4 to provide anti-alias filtering.

The low-pass cutoff frequency should be chosen to be approximately 20kHz to 25kHz for a 12kHz system, or 25kHz to 30kHz for a 16kHz system.

i.e.

)4R or 1R(×f××2

1

=C

0

When anti-alias capacitors are used, an allowance must be made for reduced gain at the SPM frequency (12kHz or 16kHz).

6 Performance Specification

6.1 Electrical Specifications

6.1.1 Absolute Maximum Ratings

Exceeding the maximum rating can result in device damage.

Parameter Min. Typ. Max. Unit

Supply Voltage (VDD-VSS) -0.3 7.0 V Voltage on any pin to V

SS

-0.3 (VDD + 0.3) V

Current

V

DD

-30 30 mA

V

SS

-30 30 mA

Any other pin -20 20 mA

D4 / P3 Packages

Total allowable device dissipation at T

AMB

25°C

800 mW

Derating above T

AMB

25°C

13

mW/°C above T

AMB

25°C

Operating Temperature -40 85

°

C

Storage Temperature -40 85

°

C

D5 Package

Total allowable device dissipation at T

AMB

25°C

550 mW

Derating above T

AMB

25°C

9

mW/°C above T

AMB

25°C

Operating Temperature -40 85

°

C

Storage Temperature -40 85

°

C

Low Voltage SPM Detector 10 CMX631A PRELIMINARY INFORMATION

4800 Bethania Station Road, Winston-Salem, NC 27105-1201 USA All trademarks and service marks are held by their respective companies.

6.1.2 Operating Limits

Correct Operation of the device outside these limits is not implied.

Parameter Min. Typ. Max. Unit

Supply Voltage (VDD) 2.7 3.0/5.0 5.5 V Operating Temperature -40 85

Xtal/Clock Frequency 3.558918 3.589368 MHz

6.1.3 Operating Characteristics

All device characteristics are measured under the following conditions unless otherwise specified: V

DD

= 3.0V to 5.0V @ T

AMB

= -40°C to 85°C

Audio Level 0dB (ref.) = 775mV

RMS

, Noise Bandwidth = 50kHz

Xtal/Clock Frequency = 3.579545MHz, System Setting = 12kHz or 16kHz

Notes Min. Typ. Max. Units

Supply Current

VDD = 3.0V 0.8 mA VDD = 5.0V 2.2 mA

Logic Inputs/Outputs

Input Logic ‘1’ 70 %V

DD

Input Logic ‘0’ 30 %V

DD

Output Logic ‘1’ 90 %V

DD

Output Logic ‘0’ 10 %V

DD

Xtal/Clock or Clock In Frequency

3.558918 3.589368 MHz

External Clock Pulse Width

High 100 ns Low 100 ns

Input Amplifier

D. C. Gain 60.0 dB Bandwidth (-3dB) 100 Hz Input Impedance 1.0

M

Ω

Logic Impedances

Input

System 0.7 3.8

M

Ω

Clock In 10.0

M

Ω

Output 14.0 30.0

k

Ω

Overall Performance

12kHz Detect Bandwidth 1 11.820 12.180 kHz 12kHz Not-detect Frequencies (below 12kHz) 1 11.520 kHz 12kHz Not-detect Frequencies (above 12kHz) 1 12.480 kHz 16kHz Detect Bandwidth 1 15.760 16.240 kHz 16kHz Not-detect Frequencies (below 16kHz) 1 15.360 kHz 16kHz Not-detect Frequencies (above 16kHz) 1 16.640 kHz Sensitivity

VDD = 3.0V±0.1V

2 -27.8 -31.8 dBm

VDD = 5.0V±0.5V

2 -23.5 -27.5 dBm

Low Voltage SPM Detector 11 CMX631A PRELIMINARY INFORMATION

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Tone Operating Characteristics

Signal-to-Noise Requirements (Amp Input) 3, 4, 5, 6 22.0 20.0 dB Signal-to-Voice Requirements (Amp Input) 3, 4, 5, 7 -36.0 -40.0 dB Signal-to-Voice Requirements (Amp Output) 5, 6 -25.0 -29.0 dB Tone Follower Mode 1, 8

Response and De-Response Time 10.0 ms

Packet Mode 1, 8

Response and De-Response Time 40.0 48.0 ms

Table 3: Operating Characteristics

Operating Characteristics Notes:

1. With adherence to Signal-to-Voice and Signal-to-Noise specifications.

2. With Input Amplifier gain set to unity gain. Reference Section 4.3 for description of sensitivity setting.

3. Common Mode SPM and balanced voice signal.

4. Immune to false responses.

5. Immune to false de-responses.

6. With SPM and voice signal amplitudes balanced. To avoid false de-responses due to saturation, the peak to peak voice+noise level at the output of the Input Amp (12/16kHz Filter Input) should be no greater than the dynamic range of the device.

7. Maximum voice frequencies = 3.4kHz.

8. Response, De-Response, and Power-up Response timing.

6.2 Packages

The CMX631A is available in the following packages. Additional package styles may be available to meet specific design requirements.

NOTE: Alldimensions in inche s(mm.)

Angles are in degrees

PackageTolerances

A B

C

E H

TYP.

MAX.MIN.

DIM.

J P X

T Y

Z

L

0.079 (2.00)0.066 (1.67)

0.312 (7.90)

0° 7° 4°

8° 9°

10°

0.037 (0.95)

0.328 (8.33)

0.213 (5.39)

0.026 (0.65)

0.022 (0.55)

0.301 (7.65)

0.008 (0.21)0.002 (0.05)

0.005 (0.13) 0.009 (0.22)

0.010 (0.25) 0.015 (0.38)

0.318 (8.07)

0.205 (5.20)

X

C

H

P

J

Y

E

Z

L

T

PIN 1

A

B

Figure 8: 24-pin SSOP Mechanical Outline:

order as part no. CMX631AD5

Low Voltage SPM Detector 12 CMX631A PRELIMINARY INFORMATION

4800 Bethania Station Road, Winston-Salem, NC 27105-1201 USA All trademarks and service marks are held by their respective companies.

PIN 1

A

B

ALTERNATIVE

PIN LOCATION MARKING

X

P

J

Y

C

K

H

E

L

T

W

Z

NOTE: Alldimensions in inches(mm.)

Angles are in degrees

PackageTolerances

A B C E H

TYP.

MAX.MIN.

DIM.

J

P

X

W

T

Y

K

L

0.105 (2.67)0.093 (2.36)

0.419 (10.64)

45°

7°

0° 10°

0.050 (1.27)

0.041 (1.04)

0.413 (10.49)

0.299 (7.59)

0.050 (1.27)

0.016 (0.41)

0.390 (9.90)

0.020 (0.51)0.003 (0.08)

0.009 (0.23) 0.0125 (0.32)

0.013 (0.33) 0.020 (0.51)

0.395 (10.03)

0.286 (7.26)

Z

5°

Figure 9: 16-pin SOIC Mechanical Outline:

order as part no. CMX631AD4

PackageTolerances

NOTE: Alldimensions in inche s(mm.)

Angles are in degrees

TYP. MAX.MIN. A B

C

E

E1

H

DIM.

J

J1

P Y

T

K

L

0.200 (5.06)

0.262 (6.63)

0.390 (9.91).

7°

0.150 (3.81)

0.810 (20.57)

0.135 (3.43)

0.100 (2.54)

0.121 (3.07)

0.300 (7.62)

0.290 (7.37) 0.325 (8.26)

0.015 (0.38) 0.070 (1.77)

0.008 (0.20) 0.015 (0.38)

0.014 (0.35) 0.023 (0.58)

0.040 (1.02) 0.065 (1.65)

0.056 (1.42) 0.064 (1.63)

0.740 (18.80)

0.240 (6.10)

B

A

PIN 1

E

Y

E1

T

K H

J1

J

C

P

L

Figure 10: 16-pin PDIP Mechanical Outline:

order as part no. CMX631AP3

Datasheet CMX631AD4, CMX631AP3, CMX631AD5 Datasheet (MX COM Inc)

Specifications and Main Features

Frequently Asked Questions

User Manual