MX COM Inc CMX602BE4, CMX602BD4 Datasheet

COMMUNICATION ICs

DATA BULLETIN

CMX602B

Calling Line Identifier

plus Call Waiting (Type II)

2000 MX-COM, Inc. www.mxcom.com tel: [phone] 744 5050 fax: [phone] Doc. # 20480204.002

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

PRELIMINARY INFORMATION

Features Applications

•

Automatic CAS Dual Tone Detector
High Sensitivity, Low Falsing
Automatic CAS Duration Checking

• 1µ

A max. 'Zero-Power' Ring or Line

Polarity Reversal Detector

•

V23/Bell202 FSK Demodulator
with Data Retiming facility

• µµ

C Interrupt / Wake-up output to

minimize system operating power

•

Low Power Operation 0.5mA at 2.7V

DD

•

Caller ID/Caller ID on Call Waiting

Telephones
Adjunct Boxes

•

Bellcore, ETSI, British Telecom, and
Mercury Systems

•

Computer Telephone Integration

•

Call Logging Systems

•

Voice Mail Equipment

XTAL XTAL

-

+

Bandpass

Filter

FSK

Demod

Level

Detector

Tone Alert

Detector

Data

Retiming

Mode

Control

Logic

RXD
RXCLK

IN-

IN+

AMPOUT

Power

Supply

Circuits

Xtal Osc and

Clock Dividers

DET

RD

RT

V

DD

V

BIAS

V

SS

ZP

MODE

Input Signal
Amplifier

IRQ

The CMX602B is a low power CMOS device used for the reception of physical layer signals in Bellcore's
Calling Identity Delivery (CID) and Calling Identity on Call Waiting (CIDCW) systems, British Telecom Calling
Line Identification Service (CLIP), the Cable Communications Association's Caller Display Services (CDS),
and similar evolving services.

This device includes a 'zero-power' ring or line polarity reversal detector, a dual-tone (2130Hz plus 2750Hz)
internally timed CPE Alerting Signal (CAS) detector, and a 1200-baud FSK Bell202/V23 compatible
asynchronous data demodulator with data retiming circuitry which removes the need for a UART in the
associated µC.

The CMX602B is suitable for use in systems using Bellcore specifications GR-30-CORE and SR-TSV­002476, British Telecom specifications SIN227 and SIN242, CCA TW/P&E/312, ETSI: ETS 300 659 parts 1
and 2 and ETS 300 778 parts 1 and 2, and Mercury Communications MNR 19.

This device may be used with a 2.7V to 5.5V supply and is available in the following packages:
16-pin TSSOP (CMX602BE4), 16-pin SOIC (CMX602BD4) and a 16-pin PDIP (CMX602BP3).

Calling Line Identifier

plus

Call Waiting (Type II) 2 CMX602B PRELIMINARY INFORMATION

2000 MX-COM, Inc www.mxcom.com Tel: [phone] 744 5050 Fax: [phone] Doc. # 20480204.002

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 Mode Control Logic ..........................................................................................................6

4.2 Input Signal Amplifier........................................................................................................ 6

4.3 Bandpass Filter................................................................................................................. 7

4.4 Level Detector .................................................................................................................. 8

4.5 FSK Demodulator.............................................................................................................8

4.6 FSK Data Retiming...........................................................................................................8

4.7 FSK Data Without Retiming.............................................................................................. 9

4.8 Tone Alert Detector......................................................................................................... 10

4.9 Ring or Line Polarity Reversal Detector.......................................................................... 10

4.10 Xtal Osc and Clock Dividers........................................................................................... 12

5. Application ...................................................................................................................12

5.1 'On-Hook' Operation....................................................................................................... 12

5.1.1 Bellcore System......................................................................................................................12

5.1.2 British Telecom System..........................................................................................................13

5.1.3 Other 'On-Hook' Systems .......................................................................................................13

5.2 'Off-Hook' Operation....................................................................................................... 15

6. Performance Specification..........................................................................................17

6.1 Electrical Performance.................................................................................................... 17

6.1.1 Absolute Maximum Ratings....................................................................................................17

6.1.2 Operating Limits......................................................................................................................17

6.1.3 Operating Characteristics .......................................................................................................18

6.2 Packaging....................................................................................................................... 21

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

Calling Line Identifier

plus

Call Waiting (Type II) 3 CMX602B PRELIMINARY INFORMATION

2000 MX-COM, Inc www.mxcom.com Tel: [phone] 744 5050 Fax: [phone] Doc. # 20480204.002

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

1. Block Diagram

XTAL

XTAL

-

+

Bandpass

Filter

FSK

Demod

Level

Detector

Tone Alert

Detector

Data

Retiming

Mode

Control

Logic

RXD

To / From µC

RXCLK

IN-

IN+

AMPOUT

R8

R6

C6

C8

C9

R5

C5

C2

C1

X1

Power

Supply

Circuits

Xtal Osc and

Clock Dividers

DET

RD

RT

V

DD

V

BIAS

V

SS

Ring or Line Polarity

Reversal Detector input

Audio band

input

(components shown

for unbalanced input)

V

DD

3.579545MHz

ZP

MODE

Input Signal

Amplifier

IRQ

Figure 1: Block Diagram

Calling Line Identifier

plus

Call Waiting (Type II) 4 CMX602B PRELIMINARY INFORMATION

2000 MX-COM, Inc www.mxcom.com Tel: [phone] 744 5050 Fax: [phone] Doc. # 20480204.002

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

2. Signal List

Pin No. Signal Type Description

1

XTAL

output Output of the on-chip Xtal oscillator inverter

2 XTAL input Input to the on-chip Xtal oscillator inverter
3 RD

input

(S)

Input to the Ring or Line Polarity Reversal Detector

4 RT

input /
output

Open-drain output and Schmitt trigger input forming part of the Ring or Line
Polarity Reversal detector. An external resistor to V

DD

and a capacitor to

V

SS

should be connected to RT to filter and extend the RD input signal

5 AMPOUT output Output of the on-chip Input Signal Amplifier
6 IN - input Inverting input to the on-chip Input Signal Amplifier
7 IN + input Non-inverting input to the on-chip Input Signal Amplifier
8

V

SS

power Negative supply

9

V

BIAS

output Internally generated bias voltage, held at V

DD

/2 when the device is not in

'Zero-Power' mode. Should be bypassed to V

SS

by a capacitor mounted

close to the device pins.

10 MODE

input

(S)

Input used to select the Tone Alert or FSK Level Detection operating mode.
See Section 4.1

11 ZP

input

(S)

High level on this input selects 'Zero-Power' mode, a low level input enables
the V

BIAS

supply, the Input signal amplifier, the Bandpass Filter , and either

the FSK or the Tone alert circuits depending on the MODE input

12

IRQ

output

Open-drain output (active low) that may be used as an Interrupt Request /
Wake-up input to the associated µC. Indicates CAS Dual Tone event of
correct duration when device is in Tone Alert Detect Mode. An external pull­up resistor should be connected between this output and V

DD

.

13 DET output

Logic level output driven by the Ring or Line Polarity Reversal Detector, the
Tone Alert Detector or the FSK Level detect circuits, depending on the
operating mode. When device is in Tone Alert Mode, it may be used as a
near end voice mute control signal. See Section 4.1

14 RXCLK input

Logic level input, which may be used to clock, received data bits out of the
FSK Data Retiming block. When held high disables FSK Data Retiming
block.

15 RXD output

Logic level output carrying either the raw output of the FSK Demodulator or
re-timed 8-bit characters depending on the state of the RXCLK input. See
Section 4.6

16

V

DD

power

Positive supply.

Levels and thresholds within the device are proportional to

this voltage. Should be bypassed to V

SS

by a capacitor mounted close to the

device pins.

Notes: input (S) = Schmitt trigger input

Table 1 : Signal List

Calling Line Identifier

plus

Call Waiting (Type II) 5 CMX602B PRELIMINARY INFORMATION

2000 MX-COM, Inc www.mxcom.com Tel: [phone] 744 5050 Fax: [phone] Doc. # 20480204.002

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

3. External Components

Line

16
15
14
13
12
11
10

9

1
2
3
4
5
6
7
8

XTAL

V

DD

V

SS

V

BIAS

AMPOUT

IN+

IN-

RD
RT

RXD
RXCLK
DET
IRQ
ZP
MODE

X1

R1

R2

R3

R4

R5

R8

R6

R7

R9 R10

R11

D1-D4

C3

C2

C1

C4

C5

C6

C7

C8

C9

V

DD

V

DD

To/From µC

Line

Protection

Network

A

B

CMX602B

XTAL

Note:

It is recommended that the printed circuit board provide a ground plane in the CMX602B area to

provide a low impedance ground connection to the V

SS

pin and to the bypass capacitors C8 and C9.

Figure 2 : Recommended External Components for Bellcore and/or British Telecom Application

R1

470kΩ

±

1%

R11

100kΩ

±

20%

R2 Note 1

±

1%

C1, C2 18pF

±

20%

R3, R4 C3, C4

0.1µF

±

20%

R5, R6

470kΩ

±

1%

C5

0.33µF

±

20%

R7 C6, C7 680pF

±

20%

R8 Note 2, 3

470kΩ @ 3.3V
680kΩ @ 5.0V

±

1%

C8,C9

0.1µF

±

20%

R9 Note 2

240kΩ @ 3.3V
200kΩ @ 5.0V

±

1%

X1 Note 4 3.579545MHz

±

0.1%

R10

160kΩ

±

1%

D1 - D4 1N4004

Table 2: Recommended External Components

Recommended External Component Notes:

1. See Section 4.8

2. See Section 4.2

3. The recommended values of R8 were selected for applications in both Bellcore and British Telecom
Systems. Optimum Bellcore-only operation may be achieved by reducing the value of R8 e.g. to 656kΩ
@ 5.0V.

4. 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.

5. It is recommended that the printed circuit board be laid out with a ground plane in the CMX602B area to
provide a low impedance ground connection to the V

SS

pin and to decoupling capacitors C8 and C9.

Calling Line Identifier

plus

Call Waiting (Type II) 6 CMX602B PRELIMINARY INFORMATION

2000 MX-COM, Inc www.mxcom.com Tel: [phone] 744 5050 Fax: [phone] Doc. # 20480204.002

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 Mode Control Logic

The CMX602B's operating mode and the source of the DET and

IRQ

outputs are determined by the logic

levels applied to the MODE and ZP input pins.

ZP MODE Mode DET output from

IRQ output from

0 0 Tone Alert Detect Tone Alert Signal Detection

Valid 'off-hook' CAS Duration.
Ring or Line Polarity Reversal Detector

0 1 FSK Receive FSK Level Detector

FSK Data Retiming (if enabled). Ring or
Line Polarity Reversal Detector.

1 0 Zero-Power

Ring or Line Polarity
Reversal Detector

Ring or Line Polarity Reversal Detector.

1 1 Zero-Power

Ring or Line Polarity
Reversal Detector

None

In the 'Zero-Power' modes, power is removed from all of the internal circuitry except for the Ring or Line
Polarity Reversal Detector and the DET and

IRQ

outputs.

4.2 Input Signal Amplifier

The Input Signal Amplifier is used to convert the balanced FSK and Tone Alert signals received over the
telephone line to an unbalanced signal of the correct amplitude for the FSK receiver and Tone Alert Detector
circuits.

-

+

V

SS

V

BIAS

AMPOUT

IN+

IN-

R8R6

R7

R9 R10

C6

C7

C9

A
B

Input Signal Amplifier

Figure 3: Input Signal Amplifier, balanced input configuration

The design equations for this circuit are:

Differential Voltage Gain

V

V

= R9 =

R8 R10

(R8 - R10)

R6 = R7 = 470k R10 = 160k

AMPOUT

(B-A)

RR8

6

×

ΩΩ

The target differential voltage gain depends on the expected A and B input signal levels and the CMX602B's
internal overload and threshold levels, which are proportional to the supply voltage.

The CMX602B has been designed to meet the applicable specifications when R8 = 430kΩ at V

DD

= 3.0V

nominal, rising to 680kΩ at V

DD

= 5.0V (see note) and R9 = 240kΩ at V

DD

= 3.0V dropping to 200kΩ at

V

DD

= 5.0V as indicated in Section 3 and as shown in Figure 5. Reference Notes found in Section 3.

Calling Line Identifier

plus

Call Waiting (Type II) 7 CMX602B PRELIMINARY INFORMATION

2000 MX-COM, Inc www.mxcom.com Tel: [phone] 744 5050 Fax: [phone] Doc. # 20480204.002

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

The Input Signal Amplifier may also be used to allow the CMX602B to operate from an unbalanced signal
source as shown in Figure 4. In this unbalanced signal configuration, the values of R6 and R8 are the same
as used for the balanced input configuration.

-

+

V

SS

V

BIAS

AMPOUT

IN+

IN-

R8R6

C6

C9

A

Input Signal Amplifier

Figure 4: Input Signal Amplifier, unbalanced input configuration

0

100

200

300

400

500

600

700

800

900

1000

3 3.5 4 4.5 5

Nominal V

DD

R8 and R9 : k

Ω

R8

R9

Figure 5: Input Signal Amplifier, Optimum Values of R8 and R9 vs. V

DD

4.3 Bandpass Filter

The Bandpass Filter is used to attenuate out of band noise and interfering signals from reaching the FSK
Demodulator, Tone Alert Detector and Level Detector circuits. The characteristics of this filter differ between
FSK and Tone Alert modes. Switched Capacitor filter stages clocked at 57.7kHz provide primary filtering. If
the input signal is band limited to below 28.85kHz then external anti-aliasing filtering is not required.