Datasheet MX826DW, MX826J, MX828DS, MX828DW, MX828P Datasheet (MX COM)

DATA BULLETIN

PRELIMINARY INFORMATION

MX826

AMPS/NAMPS SYSTEM

AUDIO PROCESSOR

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

Features

• Full-Duplex Audio Processing for AMPS/ NAMPS Cellular Systems

• On-Chip Speech and SAT Capabilities

– TX/RX Filtering & Gain – SAT Channel Pre-/De-Emphasis – Deviation Limiter

• Serial

µµ

µProcessor Interface

• “Sidetone” Output Available

• Access to External Processes

– Companding – Signaling – VSR Codec (Store/Play)

Figure1 - The MX826 AMPS/NAMPS Audio Processor Installed in a Cellular System

• HandsFree Compatibility

• Powersave (Low-Current) Settings

MX826DW MX826J

28-pin SOIC 28-pin CDIP

AMPS/NAMPS System Audio Processor. MX826 Preliminary Information

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

Description

The MX826 is a µProcessor controlled full-duplex

audio processor on a single-chip with separate TX and RX paths to provide all the filter/gain/limiting functions necessary to pre-process audio, wideband-data and SAT cellular communications systems using the AMPS/NAMPS or TACS/ETACS/JTACS specifications.

Selectable inputs available to the transmit path are: a

choice of two microphones and DTMF/signaling, with access, in this path, to external compression circuitry. Operationally the TX path provides input gain/filtering, a deviation limiter and TX Modulation Drive controls.

In the RX path the SAT signal is separated from the

incoming audio via a filter block and made available at a separate pin for mixing externally with the TX Modulation Drive.

The RX path consists of an input gain/filter block for

voice, inputs from an external audio expansion system and an output gain control driving either a loudspeaker system or earpiece.

Unique to the MX816/826/836 cellular audio processors is the ability to route audio (TX or RX) to an external Voice Store and Retrieve (VSR) device such as the MX802 or MX812 thus providing the radio system with a voice answering and announcement facility using external DRAM.

As a member of the DBS800 family, the MX826 follows C-BUS protocol. (C-BUS is the serial interface used by all DBS800 integrated circuits.)

The MX826, a low-power CMOS device which reduces the amount of microcircuits and components required in a cellular audio system by providing more functions on a single chip, is available in 28-pin SOIC and CDIP packages.

1 Xtal: The output of the on-chip clock oscillator. 2 Xtal/Clock: The input to the on-chip clock oscillator. A Xtal or externally derived clock (f

XTAL

) should be connected here. Note that operation of the MX826 without a suitable Xtal or clock input may cause device damage. See Figure 2 (notes).

3 Serial Clock: The “C-BUS” serial data clock input. This clock, produced by the µController, is used for

transfer timing of commands and data to the MX826. See Timing Diagrams.

4 Command Data: The “C-BUS” serial data input from the µController. Data is loaded to the MX826 in 8-

bit bytes, MSB (B7) first, and LSB (B0) last, synchronized to the Serial Clock. See Timing Diagrams.

5 Chip Select (CS): The “C-BUS” data loading control function. This input is provided by the µController.

Data transfer sequences are initiated, completed or aborted by this signal. See Timing Diagrams.

6V

BIAS

: The internal circuitry bias line, held at VDD/2 this pin must be decoupled to VSS. See Figure 2.

7 Rx Audio In: Normally taken from the radio's discriminator output, this input has a 1MΩ internal resistor

to V

BIAS

and requires to be connected via a capacitor.

8 Expand/Store: A common output that can be used as either an input to an external audio expander or

the input to a voice storage medium such as the MX812. Components relevant to the external device requirements should be used at this output. See Figures 2 and 3.

9 (Expanded) Audio In: The audio input, via SW5, from an external expander or audio mixing function. This

input has a 1MΩ internal resistor to V

BIAS

and requires to be connected via a capacitor. See Figures 2 and

3.

10 TX Mod Out: The composite TX audio output to the transmitter modulator from a variable attenuation

stage (11H). This output is set to V

BIAS

via an internal 1MΩ resistor when set to Powersave or OFF.

11 LS Audio Out: An audio output of the Rx path (or selected audios, see Figure 3) for a loudspeaker system.

This is available for handsfree operation. This output can be connected to V

BIAS

when not required, by SW6

(Configuration Command (10H)). A driver amplifier may be required.

Notes on Inputs: To minimize aliasing effects, lowpass filtering may be required at the inputs to this device (especially those supplied from switched-capacitor-type devices) to ensure the input spectrum is kept below 63kHz.

Pin Function

AMPS/NAMPS System Audio Processor. MX826 Preliminary Information

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

12 Ear Audio Out: An audio output of the Rx path (or selected audios), available as an output for a handset

earpiece. This output, in parallel with the LS Audio Out function, can be connected to V

BIAS

when not

required, by SW7 (Configuration Command (10H)). A driver amplifier may be required.

13 Sidetone: A switched “sidetone” from the microphone inputs made available for mixing externally with

the “Ear” audio. See Figure 3.

14 VSS: Negative supply rail. Signal ground.

15 TX Mix: The output of the TX Mix Amplifier. Used with external components, it allows the TX Filter

Out output to mix with externally generated signalling tones prior to the final level adjustment.

16 SAT Out: The output of the SAT Bandpass filter. This level is recovered from the input RX audio and

is available for mixing externally with the transmitter modulation. See Figure 3.

17 TX Mix In: The input to the TX Mix Amplifier. Used with external components, it allows the TX Filter

Out output to mix with externally generated signalling tones prior to the final level adjustment. The recovered SAT signal may be introduced at this point. See Figures 2 and 3.

18 TX Filter Out: The output of the Deviation Limiter/Lowpass Filter stage. This stage can be by-passed

using SW3 (Configuration Command). See Figure 3. 19 No internal connection – Leave open circuit. 20 Deviation Limiter In: Input to the on-chip deviation limiter. This input should be a.c. coupled to the

Pre-Emphasis Out pin. The a.c. coupling will achieve maximum possible symmetry of limiting as this

input has a 1MΩ internal resistor to V

BIAS

. See Figure 2.

21 Pre-Emphasis Out: Audio output from the TX Gain/Pre-Emphasis function. This output should be

a.c. coupled to the Deviation Limiter In pin. See Figures 2 & 3. 22 DTMF In: To introduce DTMF type audio, at a suitable level for transmission, to the TX Path,

controlled by SW2 (Configuration Command (10H)). This input has an internal 1MΩ resistor to V

BIAS

and should be connected via a capacitor. 23 Compression In: The audio input from an external compression system. This input has an internal

1MΩ resistor to V

BIAS

and should be connected via a capacitor.

24 Compression: The output to an external audio compression system. Currently available compressor/

expanders have Op-Amps incorporated. The compressor can be by-passed by SW2.

25 Mic.2 In:

26 Mic.1 In: 27 Play In: The input via SW2 from a voice storage device such as the MX812. This “replayed” audio

can be sent to RX or TX paths allowing a Messaging/Voice Notepad/Answering facility. This input has

an internal 1MΩ resistor to V

BIAS

and should be connected via a capacitor.

28 VDD: Positive supply rail. A single +5-volt power supply is required. Levels and voltages within this

Audio Processor are dependent upon this supply.

C-BUS is MX-COM’s proprietary standard for the transmission of commands and data between a µController and the relevant Cellular microcircuits. It may be used with any µController, and can, if desired, take advantage of the hardware serial I/O functions embodied into many types of µController . The “C-BUS” data rate is determined solely by the µController.

Pin Function

TX voice (Mic.) inputs, selectable by SW1 available for handsfree mic./handset mic. or any TX audio input. Pre-amplification may be required at these inputs. These inputs each have an internal 1MΩ resistor to V

BIAS

and should be connected via a capacitor.

AMPS/NAMPS System Audio Processor. MX826 Preliminary Information

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

Application Information

Notes

1. Xtal/clock operation

Operation of any MX-COM IC without a Xtal or clock input may cause device damage. To minimize damage in the event of a Xtal/drive failure, you should install a current limiting device (resistor or fast-reaction fuse) on the power input (VDD).

Figure 2 - Recommended External Components

Tolerances – Capacitors ±20%

C3= 100nF C

4

100nF

C

5

100nF

C

6

100nF

C

7

100nF

C13= 100nF C

14

100nF

C

15

100pF

C

16

100nF

X

1

4.000MHz

R1= 100kΩ R

2

as required

R

3

100kΩ

R

4

as required

C

1

100nF

C

2

100nF

C8= 100nF C

9

33pF

C

10

100nF

C

11

33pF

C

12

1.0µF

2. SAT Output

It is possible, due to the impedance of this output, that an external buffer amplifier will be required when interfacing or mixing with other cellular system sections.

3. TX Mix Gain

The value of R4 should be chosen with R3/C15 in order to provide the required gain.

XTAL/CLOCK

SERIAL CLOCK

COMMAND DATA

V

BIAS

RX AUDIO IN

EXPAND/STORE

(EXPANDED) AUDIO IN

TX MOD OUT

LS AUDIO OUT

EAR AUDIO OUT

SIDETONE OUT

V

SS

SAT OUT

TX MIX IN

TX FILTER OUT

DEV LIM IN

PRE-EMP OUT

DTMF IN

(COMPRESSED) AUDIO IN

COMPRESS

MIC.2 IN

MIC.1 IN

PLAY IN

V

DD

CHIP SELECT

V

DD

XTAL

C

11

C

9

X

1

C

4

C

8

C

12

C

7

C

6

C

5

C

1

C

3

C

10

MX826J

1 2 3 4 5 6 7 8

9 10 11 12 13 14

28 27 26 25 24 23 22 21

20 19 18 17 16 15

TX MIX

C

13

C

2

Signaling and

Wideband Data

C

14

C

15

C

16

R

1

R

3

R

4

R

2

AMPS/NAMPS System Audio Processor. MX826 Preliminary Information

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

Figure 3 - The MX826 Internal and External Signal Paths within a AMPS/NAMPS Cellular Radio System

AMPS/NAMPS Cellular System Interfaces

INTERFACE

MOD LEVEL

MIC.2 IN

MIC.1 IN

DTMF IN

COMPRESSION IN

COMPRESSION

PLAY IN

PRE-EMP.

OUT

DEV.

LIMITER IN

TX FILTER

OUT

TX MIX

IN

TX MOD OUT

SIDETONE OUT

SAT OUT

EAR AUDIO OUT

LS AUDIO OUT

EXPAND/STORE

(EXPANDED)

AUDIO IN

SERIAL CLOCK

COMMAND DATA

SW5

SERIAL

C-BUS

and

LOGIC

BIAS

SIDETONE

BIAS

VOLUME

SAT

XTAL/CLOCK

COMP.

BYPASS

SIDETONE

BYPASS

TX AUDIO/PLAY/STORE

SIDETONE

ENABLE

AUDIO

SELECT

SW8

#

SW7

SW6

SW4

RX Path

TX Path

SW1

SW2

XTAL

#

CLOCK

GENERATOR

DEV LIMITER

SW3

CHIP SELECT

DE-EMP

RX GAIN

dB

PRE-EMP

TX GAIN ELEMENT

TX GAIN

RX GAIN ELEMENT

MX812

C-BUS

CONTROL

INPUTS

XTAL/CLOCK

COMPONENTS

(SEE FIGURE 2)

TO

MODULATOR

EXPANDER

DTMF

ALARM

EARPIECE

HANDSFREE

LOUDSPEAKER

COMPRESSOR

STORE AUDIO

MIXING

NETWORK

MIXING

NETWORK

LPF

-

+

TX MIX

V

SS

V

BIAS

V

DD

TX MIX AMP

BIAS

SIGNALING and

WIDEBAND DATA IN

FROM

DEMODULATOR

(OPTIONAL

VSR CODEC)

Mixing SAT, TX Signal & Signaling

prior to final drive adjustment...

Note that SAT & TX Mod Out may

be mixed prior to modulation.

RX AUDIO IN

HPF

SAT

BPF

AMPS/NAMPS System Audio Processor. MX826 Preliminary Information

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

Control Bits

Transmitted First

Sw8 Sidetone

Sidetone Bias

Sidetone Enabled

Sw6/7 RX Audio

Ear Enabled, LS Bias LS Enabled, Ear Bias

Sw5 Expandor

Expander By-Pass

Expander Route

Sw4 TX/RX Audio

Tx Store/Audio Rx Store/Audio

Sw3 Dev. Limiter

Dev. Limiter Bypass

Dev. Limiter Route

Sw1 Mic. Inputs

Mic. 1 Input

Mic.2 Input

Sw2 TX Function

DTMF In

Compressor Bypass

Compressor In

Play In

Setting

MSB Bit 7

0 1

6

0 1

5

0 1

4

0 1

3

0 1

2

0 1

10

00 01 10 11

Setting

MSB

7654

0000 0001 0010 0011 0100 0101 0110 0111 1000 1001 1010 1011 1100 1101 1110 1111

3210

0000 0001 0010 0011 0100 0101 0110 0111 1000 1001 1010 1011 1100 1101 1110 1111

Gain (dBs)

Transmitted First

Tx Mod. Level

OFF (Low Z to V

BIAS

)

-5.6

-5.2

-4.8

-4.4

-4.0

-3.6

-3.2

-2.8

-2.4

-2.0

-1.6

-1.2

-0.8

-0.4 0

TX Input Gain

-2.65

-2.05

-1.50

-0.95

-0.45 0

0.45

0.85

1.25

1.65

2.05

2.40

2.70

3.05

3.35

3.65

Table 3 TX Gain & Mod. Commands

Table 2 Configuration Commands

Command Address/Command (A/C) Byte Command Table Assignment Hex Binary Data

MSB LSB

General Reset 01 00000001 Configuration Command 10 00010000 + 1 byte 2 TX Gain & Mod. Command 11 00010001 + 1 byte 3 RX Gain & Vol. Command 12 00010010 + 1 byte 4

Powersave Command 13 00010011 + 1 byte 5

Table 1 “C-Bus” Address/Commands

Configuration Command

(

Preceded by A/C 10H)

TX Gain & Mod. Command

(Preceded by A/C 11H)

In C-BUS protocol the audio processor is allocated

Address/Command (A/C) values 10

H

to 13H. Configuration, TX/ RX Gains, Powersave assignments and data requirements are given in Table 1. Each instruction consists of an Address/ Command (A/C) byte followed by a data instruction formulated from the following tables.

Commands and Data are only to be loaded in the group

configurations detailed, as the C-BUS interface recognizes the

first byte after Chip Select (logic “0”) as an Address/Command. Function or Level control data, which is detailed in Tables 2, 3, 4 and 5, is acted upon at the end of the loaded instruction. See Timing Diagrams, Figures 5 and 6.

Upon Power-Up the value of the “bits” in this device will be

random (either “0” or “1”). A General Reset Command (01

H

)

will be required to set all MX826 registers to 00H.

The Controlling System: C-BUS Hardware Interface

C-BUS is MX-COM's proprietary standard for the transmission of commands and data between a µController and MXCOM's New Generation integrated circuits. C-BUS has been designed for a low IC pin-count, flexibility in handling variable amounts of data, and simplicity of system design and µController software.

It may be used with any µController, and can, if desired, take advantage of the hardware serial I/O functions built into many types of µController. Because of this flexibility and because the BUS data-rate is determined solely by the µController, the system designer has complete freedom to choose a µController appropriate to the overall system processing requirements.

Control of the functions and levels within the MX826 is by a group of Address/Commands and appended data instructions from the system µController to set/adjust the functions and elements of the device. The use of these instructions is detailed in the following paragraphs and tables.

AMPS/NAMPS System Audio Processor. MX826 Preliminary Information

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

Figure 4 - Signal Deviation Levels and corresponding TX Mod Outputs with the Mod Level set to 0dB

Reference Signal Levels

Gain (dBs)

Transmitted First

RX Volume

OFF (Low Z to V

BIAS

)

-28.0

-26.0

-24.0

-22.0

-20.0

-18.0

-16.0

-14.0

-12.0

-10.0

-8.0

-6.0

-4.0

-2.0 0

RX Input Gain

3.75

4.30

4.80

5.30

5.80

6.20

6.55

7.05

7.40

7.80

8.15

8.50

8.80

9.10

9.40

9.70

Setting

MSB

7654

0000 0001 0010 0011 0100 0101 0110 0111 1000 1001 1010 1011 1100 1101 1110 1111

3210

0000 0001 0010 0011 0100 0101 0110 0111 1000 1001 1010 1011 1100 1101 1110 1111

Table 4 - RX Gain and Vol. Commands

The Controlling System ......

RX Gain & Vol. Command

(

Preceded by A/C 12H)

Control Bits

Transmitted First

All must be a logic “0”

Powersave Setting

Powersave MX826

Enable MX826

Setting

MSB Bit 7

7654321

0000000

0

0 1

Powersave Command

(Preceded by A/C 13H)

Table 5 - Powersave Command

10

20

103 1.9

30

40

50

60

70

80

90

100

%kHz

mV

(rms)

Signaling

Tone

10kHz

and WBD

205 3.8

308 5.7

411 7.6

513 9.5

DEVIATION (+/-)

1.0kHz

Tone

24.2%

2.3kHz

125mV

Maximum

Deviation

100%

9.5kHz

513mV

SATTone

5970kHz 6000kHz 6030kHz

17.9%

1.7kHz

92mV

Normal

Test

Modulation

67.4%

6.4kHz

346mV

Min.

697Hz

60.0%

5.7kHz

308mV

Max.

1633Hz

12.6%

1.2kHz

65mV

37.1%

3.52kHz

190mV

DTMF

AMPS/NAMPS System Audio Processor. MX826 Preliminary Information

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

Figure 6 - Control Timing Relationships

Figure 5 - Control Timing Information

Control Timing Information

Characteristics See Note Min. Typ. Max. Unit

t

CSE

“CS-Enable to Clock-High” 1 2.0 – – µs

t

CSH

Last “Clock-High to CS-High” 1 4.0 – – µs

t

CSOFF

“CS-High” Time between transactions 1, 2 2.0 – – µs

t

CK

“Clock-Cycle” Time 1 2.0 – – µs

t

NXT

“Inter-Byte” Time 1 4.0 – – µs

t

CH

“Serial Clock-High” Period 500 – – ns

t

CL

“Serial Clock-Low” Period 500 – – ns

t

CDS

“Command Data Set-Up” Time 250 – – ns

t

CDH

“Command Data Hold” Time 0 – – ns

Notes

1. These Minimum Timing values are altered during operation of the MX812 VSR Codec.

2. Chip Select must be taken to a logic “1” between each individual transaction.

➤

AMPS/NAMPS System Audio Processor. MX826 Preliminary Information

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

Frequency Responses

Figure 7 - Microphone Input Stages -Combined Low and Highpass Filter Frequency Response

Figure 7

Mic.1/2 In to Compression Out

V

DD

= 5.0V

Signal Input Level = 55.0mVrms

Figure 8

Dev Limiter In to TX Filter Out

V

DD

= 5.0V

Signal Input Level = 55.0mVrms

Figure 9 - RX SAT Path Bandpass Filter Response

Figure 8 - Post Deviation Limiter Lowpass Filter Response

Figure 9

RX Audio In to SAT out

V

DD

= 5.0V

Signal Input Level = 100mVrms

100030010050

-40

-30

dB

-20

-10

0

10

3000 10000

Frequency (Hz)

dB

-50

-40

-30

-20

-10

0

10

Frequency (Hz)

2000

3000

4000

6000

10000

3000

-50

-40

-30

-20

20

-10

0

10

6000

10000

Frequency (Hz)

dB

AMPS/NAMPS System Audio Processor. MX826 Preliminary Information

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

Characteristics See Note Min. Typ. Max. Unit Static Values

Supply Voltage 4.5 5.0 5.5 V Supply Current

Operating – 6.5 – m A Powersave – 0.5 – m A

Alias Frequency – 63.0 – kHz

On-Chip Xtal Oscillator

R

IN

10.0 – – MΩ

R

OUT

– 10.0 – kΩ Inverter d.c. Voltage Gain – 10.0 – V/V Gain/Bandwidth Product – 10.0 – MHz TX Mix Amp (Open Loop Gain) – 50.0 – dB

(Bandwidth) 20.0 – – kHz

Analog Input Impedances

Mic.1 & 2 – 500 – kΩ Play – 500 – kΩ Comp In – 500 – kΩ DTMF In – 500 – kΩ Dev. Limiter In – 100 – kΩ (Expanded) Audio In – 47.0 – kΩ TX Mix In 10.0 – – MΩ RX Audio In – 100 – kΩ

Analog Output Impedances

Pre-Emp Out – 600 – Ω TX Mod Out – 600 – Ω Expand/Store – 600 – Ω LS and Ear Audio – 1.0 – kΩ SAT Out 3 – 1.0 – kΩ TX Filter Out – 600 – Ω Comp Out – 600 – Ω Sidetone Out – 2.0 – kΩ TX Mix (Open Loop) – 6.0 – kΩ

(Closed Loop) – 600 – Ω

Switches – ON – 1.0 – kΩ

– OFF 10.0 – – MΩ

Specifications

Absolute Maximum Ratings

Exceeding the maximum rating can result in device damage. Operation of the device outside the operating limits is not suggested.

Supply Voltage -0.3 to 7.0 V Input Voltage at any pin

(Ref VSS = 0V) -0.3V to (VDD + 0.3V)

Sink/source Current

(Supply pins) ±30mA (Other pins) ±20mA

Total Device Dissipation

@T

AMB

25°C 800mW max. Derating 10mW/°C Operating Temperature -40°C to +85°C Storage Temperature -55°C to +125°C

Operating Limits

All devices were measured under the following

conditions unless otherwise noted.

VDD = 5.0V

T

AMB

= 25°C

Xtal/clock f

XTAL

= 4.0MHz

Audio level 0dB ref. = 308mVrms @ 1kHz

AMPS/NAMPS System Audio Processor. MX826 Preliminary Information

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

Characteristics See Note Min. Typ. Max. Unit

Control Interface Parameters

Input Logic Levels

Logic “1” 1 3 .5 – – V

Logic “0” 1 – – 1.5 V IIN (logic “1” or “0”) 1 -1.0 – 1.0 µA Input Capacitance 1 – – 7.5 pF

Channel Performances TX Path

Filter Specifications

Pre-Compression L/HPF Combination

Passband 300 3000 Hz

Slope - below 300Hz +24.0 – – dB/oct.

above 3000Hz -24.0 – – dB/oct.

TX Gain Pre-Emphasis

Gain at 1.0kHz – 0 – dB

Slope (300Hz - 3000Hz) – 6.0 – dB/oct.

Post Deviation Limiter LPF

Attenuation Relative to 1.0kHz

3.0kHz - 5.9kHz - 40 log(f/3000) - dB

5.9kHz - 6.1kHz - 35.0 - dB

6.1kHz - 15kHz - 40 log(f/3000) - dB >15kHz - 28.0 - dB

Analog Signal Input Levels

Mic. 1 and 2 2 – 0 – dB

Play 2 – 0 – dB

DTMF 2 – 0 – dB

Comp. In 2 – 0 – dB

TX Mix In 2 – 0 – dB

Analog Signal Output Levels

Pre-Emp Out 2 – 0 – dB

TX Filter Out 2 – 0 – dB

TX Mod Out 2 – 0 – dB

Sidetone Out 2 – 0 – dB

Path Gains/Levels TX Gain – 11

H

Nominal Adjustment Range -2.65 – 3.65 dB

Error of any Setting -0.2 – 0.2 dB

Dev Limiter

Threshold – 1086 – mVp-p

Symmetry – 7.0 – %

Mod Level Attenuation – 11

H

Nominal Adjustment Range -5.6 0 dB

Step Size 0.2 0.4 0.6 dB

Error of any Setting -1.0 – 1.0 dB

Overall

TX Distortion – -40.0 -32.0 dBp

TX Hum and Noise – -40.0 -20.0 dB

RX Signal Path

Filter Specifications

RX Gain De-Emphasis

Gain at 1.0kHz – 3.75 – dB

Slope (300Hz - 3000Hz) – -6.0 – dB/oct.

RX Channel Bandpass 300 3000 Hz

Slope - below 300Hz +24.0 – – dB/oct.

above 3000Hz -36.0 – – dB/oct.

AMPS/NAMPS System Audio Processor. MX826 Preliminary Information

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

RX Signal Path (cont'd)

Analog Signal Levels

RX Audio Input Level 2 – -7.0 – dB

LS/Ear Audio Output Level 2 – 0–dB

Path Gains/Levels RX Gain – 12

H

Nominal Adjustment Range 3.75 9.70 dB

Error of any Setting -0.2 – 0.2 dB

Volume – 12

H

Nominal Adjustment Range -28.0 0 dB

Step Size 1.5 2.0 2.5 dB

Error of any Setting -1.0 – 1.0 dB

Overall

RX Distortion – -40.0 -32.0 dBp

RX Hum and Noise – -40.0 -34.0 dB

SAT Signal Path

Bandpass Filter

Frequency Range 5970 6030 Hz

Gain 19.0 20.0 21.0 dB

Notes

1. Serial Clock, Command Data and Chip Select inputs.

2. Levels equivalent to ±3.0kHz deviation with the settings below:

TX Gain = 0dB Mod Level = 0dB RX Gain = 7.05dB Volume = 0dB

Other levels can be achieved by adjusting the above variable gain blocks in accordance with Tables 1 to 5.

3. Recommended load >10.0kΩ.

Characteristics See Note Min. Typ. Max. Unit

AMPS/NAMPS System Audio Processor. MX826 Preliminary Information

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

Package Outline

The MX826 packages available are shown below. Pin 1 is marked with an indent spot. Pins on both package styles number counter-clockwise when viewed from the top (marked side).

Handling Precautions

The MX826 is a CMOS LSI circuit which includes input protection. However precautions should be taken to prevent static discharges which may cause damage.

R

P

J

K

M

L

N

➤

A

B

➤

➤➤

➤

➤➤

F

G

E

C

H

D

PackageTolerances

Fig.10 MX826DW 28-pin Small Outline I.C. Package

➤

J

K

L

➤

A

B

➤

E

F

G

C D

H

Package T oler ances

Fig.11 MX826J 28-pin Ceramic Dual In-Line Package

Datasheet MX826DW, MX826J, MX828DS, MX828DW, MX828P Datasheet (MX COM)

Specifications and Main Features

Frequently Asked Questions

User Manual