DATA BULLETIN AMPS/NAMPS SYSTEM AUDIO PROCESSOR MX826 PRELIMINARY INFORMATION 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 µProcessor Interface • “Sidetone” Output Available • Access to External Processes – Companding – Signaling – VSR Codec (Store/Play) • HandsFree Compatibility • Powersave (Low-Current) Settings MX826DW 28-pin SOIC MX826J 28-pin CDIP Figure1 - The MX826 AMPS/NAMPS Audio Processor Installed in a Cellular System © 1997 MX•COM Inc. www.mxcom.com Tele: 800 638-5577 910 744-5050 Fax: 910 744-5054 Doc. # 20480070.004 4800 Bethania Station Road, Winston-Salem, NC 27105-1201 USA All trademarks and service marks are held by their respective companies. AMPS/NAMPS System Audio Processor. MX826 Preliminary Information 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 Pin 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. Function 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 (fXTAL) 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 8bit 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. 6 VBIAS: 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 VBIAS 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 VBIAS 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 VBIAS 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 VBIAS 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. © 1997 MX•COM Inc. www.mxcom.com Tele: 800 638-5577 910 744-5050 Fax: 910 744-5054 Doc. # 20480070.004 4800 Bethania Station Road, Winston-Salem, NC 27105-1201 USA All trademarks and service marks are held by their respective companies. AMPS/NAMPS System Audio Processor. Pin MX826 Preliminary Information Function 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 VBIAS 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 VBIAS. 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 VBIAS 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 VBIAS 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. 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 VBIAS and should be connected via a capacitor. 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 ofµController. The “C-BUS” data rate is determined solely by the µController. © 1997 MX•COM Inc. www.mxcom.com Tele: 800 638-5577 910 744-5050 Fax: 910 744-5054 Doc. # 20480070.004 4800 Bethania Station Road, Winston-Salem, NC 27105-1201 USA All trademarks and service marks are held by their respective companies. AMPS/NAMPS System Audio Processor. MX826 Preliminary Information Application Information VDD X1 C11 C9 XTAL 1 28 VDD XTAL/CLOCK 2 27 PLAY IN 3 4 26 25 MIC.1 IN C1 MIC.2 IN C2 SERIAL CLOCK COMMAND DATA CHIP SELECT VBIAS C 4 RX AUDIO IN EXPAND/STORE C8 (EXPANDED) AUDIO IN C12 TX MOD OUT LS AUDIO OUT EAR AUDIO OUT SIDETONE OUT VSS 24 23 5 6 7 8 9 MX826J C3 C10 COMPRESS (COMPRESSED) AUDIO IN 22 21 20 DTMF IN C5 C6 PRE-EMP OUT C DEV LIM IN 10 11 19 18 12 13 17 16 TX MIX IN 14 15 TX MIX TX FILTER OUT SAT OUT C13 7 R1 C14 R2 R3 C15 C16 Signaling and Wideband Data R4 R1 R2 R3 R4 C1 C2 = 100kΩ as required 100kΩ as required 100nF 100nF Tolerances – C3 C4 C5 C6 C7 = 100nF 100nF 100nF 100nF 100nF C8 C9 C10 C11 C12 = 100nF 33pF 100nF 33pF 1.0µF C13 C14 C15 C16 X1 = 100nF 100nF 100pF 100nF 4.000MHz Capacitors ±20% Figure 2 - Recommended External Components 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). 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. © 1997 MX•COM Inc. www.mxcom.com Tele: 800 638-5577 910 744-5050 Fax: 910 744-5054 Doc. # 20480070.004 4800 Bethania Station Road, Winston-Salem, NC 27105-1201 USA All trademarks and service marks are held by their respective companies. MX812 XTAL/CLOCK COMPONENTS (SEE FIGURE 2) C-BUS CONTROL INPUTS CLOCK STORE AUDIO RX Path RX AUDIO IN XTAL GENERATOR XTAL/CLOCK CHIP SELECT COMMAND DATA SERIAL CLOCK DTMF IN SW1 HPF COMP. BYPASS RX GAIN ELEMENT RX GAIN DE-EMP # HPF SERIAL C-BUS INTERFACE and LOGIC LPF COMPRESSION SW2 SAT BPF ALARM DTMF SW4 EXPANDER LPF SAT dB VOLUME SIDETONE BYPASS (EXPANDED) AUDIO IN SW5 MIXING NETWORK EXPAND/STORE LPF TX AUDIO/PLAY/STORE SIDETONE TX GAIN PRE-EMP DEV LIMITER PRE-EMP. DEV. LIMITER IN OUT TX GAIN ELEMENT COMPRESSION IN SIGNALING and WIDEBAND DATA IN SW3 TX FILTER OUT Figure 3 - The MX826 Internal and External Signal Paths within a AMPS/NAMPS Cellular Radio System FROM DEMODULATOR (OPTIONAL VSR CODEC) PLAY IN MIC.2 IN MIC.1 IN TX Path COMPRESSOR AMPS/NAMPS Cellular System Interfaces TX MIX + - TX MIX AMP BIAS # BIAS SW6 AUDIO SELECT SW7 SIDETONE ENABLE SW8 BIAS BIAS TX MIX IN SAT OUT VBIAS SIDETONE OUT VDD LS AUDIO OUT VSS EAR AUDIO OUT dB TX MOD OUT MOD LEVEL EARPIECE TO MODULATOR HANDSFREE LOUDSPEAKER MIXING NETWORK Mixing SAT, TX Signal & Signaling prior to final drive adjustment... Note that SAT & TX Mod Out may be mixed prior to modulation. AMPS/NAMPS System Audio Processor. MX826 Preliminary Information © 1997 MX•COM Inc. www.mxcom.com Tele: 800 638-5577 910 744-5050 Fax: 910 744-5054 Doc. # 20480070.004 4800 Bethania Station Road, Winston-Salem, NC 27105-1201 USA All trademarks and service marks are held by their respective companies. AMPS/NAMPS System Audio Processor. MX826 Preliminary Information 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. Command Assignment Address/Command (A/C) Byte Hex Binary MSB Command Data Table LSB General Reset Configuration Command TX Gain & Mod. Command RX Gain & Vol. Command 01 10 11 12 0 0 0 0 0 0 0 0 0 0 0 0 0 1 1 1 0 0 0 0 0 0 0 0 0 0 0 1 1 0 1 0 + + + 1 byte 1 byte 1 byte 2 3 4 Powersave Command 13 0 0 0 1 0 0 1 1 + 1 byte 5 Table 1 “C-Bus” Address/Commands In C-BUS protocol the audio processor is allocated Address/Command (A/C) values 10H 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 (01H) will be required to set all MX826 registers to 00H. Configuration Command TX Gain & Mod. Command (Preceded by A/C 11H) Setting 1 0 0 1 1 (Preceded by A/C 10H) Control Bits MSB Bit 7 0 1 Transmitted First Sw8 Sidetone Sidetone Bias Sidetone Enabled 6 0 1 Sw6/7 RX Audio Ear Enabled, LS Bias LS Enabled, Ear Bias 5 0 1 Sw5 Expandor Expander By-Pass Expander Route 4 0 1 Sw4 TX/RX Audio Tx Store/Audio Rx Store/Audio 3 0 1 Sw3 Dev. Limiter Dev. Limiter Bypass Dev. Limiter Route 2 0 1 Sw1 Mic. Inputs Mic. 1 Input Mic.2 Input 0 0 1 0 1 Sw2 TX Function DTMF In Compressor Bypass Compressor In Play In Table 2 Configuration Commands Setting MSB 7 0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 1 3 0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 1 Gain (dBs) 6 0 0 0 0 1 1 1 1 0 0 0 0 1 1 1 1 5 0 0 1 1 0 0 1 1 0 0 1 1 0 0 1 1 4 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 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 2 0 0 0 0 1 1 1 1 0 0 0 0 1 1 1 1 1 0 0 1 1 0 0 1 1 0 0 1 1 0 0 1 1 0 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 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 © 1997 MX•COM Inc. www.mxcom.com Tele: 800 638-5577 910 744-5050 Fax: 910 744-5054 Doc. # 20480070.004 4800 Bethania Station Road, Winston-Salem, NC 27105-1201 USA All trademarks and service marks are held by their respective companies. AMPS/NAMPS System Audio Processor. MX826 Preliminary Information The Controlling System ...... RX Gain & Vol. Command (Preceded by A/C 12H) Setting MSB 7 0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 1 3 0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 1 Powersave Command Gain (dBs) 6 0 0 0 0 1 1 1 1 0 0 0 0 1 1 1 1 5 0 0 1 1 0 0 1 1 0 0 1 1 0 0 1 1 4 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 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 2 0 0 0 0 1 1 1 1 0 0 0 0 1 1 1 1 1 0 0 1 1 0 0 1 1 0 0 1 1 0 0 1 1 0 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 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 Bit 7 7 6 0 0 (Preceded by A/C 13H) Control Bits Transmitted First 5 0 4 0 3 0 2 0 1 0 All must be a logic “0” 0 0 1 Powersave Setting Powersave MX826 Enable MX826 Table 5 - Powersave Command Table 4 - RX Gain and Vol. Commands Reference Signal Levels % (rms) mV kHz 100 513 9.5 411 7.6 100% 9.5kHz 513mV 90 DEVIATION (+/-) 80 67.4% 6.4kHz 70 60 346mV 308 5.7 205 3.8 60.0% 5.7kHz 308mV 50 40 37.1% 3.52kHz 190mV 24.2% 2.3kHz 30 20 125mV 103 17.9% 1.7kHz 12.6% 1.2kHz 92mV 1.9 65mV 10 Maximum Deviation 1.0kHz Tone SAT Tone 5970kHz 6000kHz 6030kHz Signaling Tone 10kHz and WBD DTMF Normal Test Modulation Min. 697Hz Max. 1633Hz Figure 4 - Signal Deviation Levels and corresponding TX Mod Outputs with the Mod Level set to 0dB © 1997 MX•COM Inc. www.mxcom.com Tele: 800 638-5577 910 744-5050 Fax: 910 744-5054 Doc. # 20480070.004 4800 Bethania Station Road, Winston-Salem, NC 27105-1201 USA All trademarks and service marks are held by their respective companies. AMPS/NAMPS System Audio Processor. MX826 Preliminary Information Control Timing Information Characteristics tCSE tCSH tCSOFF tCK tNXT tCH tCL tCDS tCDH See Note Min. Typ. Max. Unit 1 1 1, 2 1 1 2.0 4.0 2.0 2.0 4.0 500 500 250 0 – – – – – – – – – – – – – – – – – – µs µs µs µs µs ns ns ns ns “CS-Enable to Clock-High” Last “Clock-High to CS-High” “CS-High” Time between transactions “Clock-Cycle” Time “Inter-Byte” Time “Serial Clock-High” Period “Serial Clock-Low” Period “Command Data Set-Up” Time “Command Data Hold” Time 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. ➤ ➤ ➤ ➤ ➤ ➤ ➤ ➤ ➤ ➤ Figure 5 - Control Timing Information ➤ ➤ ➤ ➤ ➤ ➤ ➤ ➤ ➤ ➤ Figure 6 - Control Timing Relationships © 1997 MX•COM Inc. www.mxcom.com Tele: 800 638-5577 910 744-5050 Fax: 910 744-5054 Doc. # 20480070.004 4800 Bethania Station Road, Winston-Salem, NC 27105-1201 USA All trademarks and service marks are held by their respective companies. AMPS/NAMPS System Audio Processor. MX826 Preliminary Information Frequency Responses 10 0 dB -10 -20 -30 -40 50 100 300 3000 1000 10000 Frequency (Hz) Figure 7 - Microphone Input Stages -Combined Low and Highpass Filter Frequency Response Figure 7 Mic.1/2 In to Compression Out 10 0 VDD dB -10 = 5.0V Signal Input Level = 55.0mVrms -20 -30 Figure 8 Dev Limiter In to TX Filter Out -40 -50 3000 2000 4000 10000 6000 Frequency (Hz) VDD = 5.0V Signal Input Level = 55.0mVrms Figure 8 - Post Deviation Limiter Lowpass Filter Response 20 10 Figure 9 VDD = Signal Input Level = dB 0 RX Audio In to SAT out -10 5.0V -20 100mVrms -30 -40 -50 3000 6000 10000 Frequency (Hz) Figure 9 - RX SAT Path Bandpass Filter Response © 1997 MX•COM Inc. www.mxcom.com Tele: 800 638-5577 910 744-5050 Fax: 910 744-5054 Doc. # 20480070.004 4800 Bethania Station Road, Winston-Salem, NC 27105-1201 USA All trademarks and service marks are held by their respective companies. AMPS/NAMPS System Audio Processor. MX826 Preliminary Information Specifications Absolute Maximum Ratings Operating Limits Exceeding the maximum rating can result in device damage. Operation of the device outside the operating limits is not suggested. All devices were measured under the following conditions unless otherwise noted. Supply Voltage Input Voltage at any pin (Ref VSS = 0V) Sink/source Current (Supply pins) (Other pins) Total Device Dissipation @TAMB 25°C Derating Operating Temperature Storage Temperature VDD = 5.0V -0.3 to 7.0 V -0.3V to (VDD + 0.3V) TAMB = 25°C Xtal/clock fXTAL = 4.0MHz ±30mA ±20mA Audio level 0dB ref. = 308mVrms @ 1kHz 800mW max. 10mW/°C -40°C to +85°C -55°C to +125°C Characteristics See Note Min. Typ. Max. Unit 4.5 5.0 5.5 V – – – 6.5 0.5 63.0 – – – mA mA kHz 10.0 – – – – 20.0 – 10.0 10.0 10.0 50.0 – – – – – – – MΩ kΩ V/V MHz dB kHz Analog Input Impedances Mic.1 & 2 Play Comp In DTMF In Dev. Limiter In (Expanded) Audio In TX Mix In RX Audio In – – – – – – 10.0 – 500 500 500 500 100 47.0 – 100 – – – – – – – – kΩ kΩ kΩ kΩ kΩ kΩ MΩ kΩ Analog Output Impedances Pre-Emp Out TX Mod Out Expand/Store LS and Ear Audio SAT Out TX Filter Out Comp Out Sidetone Out TX Mix (Open Loop) (Closed Loop) Switches – ON – OFF – – – – – – – – – – – 10.0 600 600 600 1.0 1.0 600 600 2.0 6.0 600 1.0 – – – – – – – – – – – – – Ω Ω Ω kΩ kΩ Ω Ω kΩ kΩ Ω kΩ MΩ Static Values Supply Voltage Supply Current Operating Powersave Alias Frequency On-Chip Xtal Oscillator RIN ROUT Inverter d.c. Voltage Gain Gain/Bandwidth Product TX Mix Amp (Open Loop Gain) (Bandwidth) 3 © 1997 MX•COM Inc. www.mxcom.com Tele: 800 638-5577 910 744-5050 Fax: 910 744-5054 Doc. # 20480070.004 4800 Bethania Station Road, Winston-Salem, NC 27105-1201 USA All trademarks and service marks are held by their respective companies. AMPS/NAMPS System Audio Processor. Characteristics MX826 Preliminary Information See Note Min. Typ. Max. Unit 1 1 1 1 3.5 – -1.0 – – – – – – 1.5 1.0 7.5 V V µA pF 300 +24.0 -24.0 – – 3000 – – Hz dB/oct. dB/oct. – – 0 6.0 – – dB dB/oct. - 40 log(f/3000) 35.0 40 log(f/3000) 28.0 - dB dB dB dB 2 2 2 2 2 – – – – – 0 0 0 0 0 – – – – – dB dB dB dB dB 2 2 2 2 – – – – 0 0 0 0 – – – – dB dB dB dB -2.65 -0.2 – – 3.65 0.2 dB dB – – 1086 7.0 – – mVp-p % -5.6 0.2 -1.0 0.4 – 0 0.6 1.0 dB dB dB – – -40.0 -40.0 -32.0 -20.0 dBp dB – – 300 +24.0 -36.0 3.75 -6.0 – – 3000 – – dB dB/oct. Hz dB/oct. dB/oct. Control Interface Parameters Input Logic Levels Logic “1” Logic “0” IIN (logic “1” or “0”) Input Capacitance Channel Performances TX Path Filter Specifications Pre-Compression L/HPF Combination Passband Slope - below 300Hz above 3000Hz TX Gain Pre-Emphasis Gain at 1.0kHz Slope (300Hz - 3000Hz) Post Deviation Limiter LPF Attenuation Relative to 1.0kHz 3.0kHz - 5.9kHz 5.9kHz - 6.1kHz 6.1kHz - 15kHz >15kHz Analog Signal Input Levels Mic. 1 and 2 Play DTMF Comp. In TX Mix In Analog Signal Output Levels Pre-Emp Out TX Filter Out TX Mod Out Sidetone Out Path Gains/Levels TX Gain – 11H Nominal Adjustment Range Error of any Setting Dev Limiter Threshold Symmetry Mod Level Attenuation – 11 H Nominal Adjustment Range Step Size Error of any Setting Overall TX Distortion TX Hum and Noise RX Signal Path Filter Specifications RX Gain De-Emphasis Gain at 1.0kHz Slope (300Hz - 3000Hz) RX Channel Bandpass Slope - below 300Hz above 3000Hz – – © 1997 MX•COM Inc. www.mxcom.com Tele: 800 638-5577 910 744-5050 Fax: 910 744-5054 Doc. # 20480070.004 4800 Bethania Station Road, Winston-Salem, NC 27105-1201 USA All trademarks and service marks are held by their respective companies. AMPS/NAMPS System Audio Processor. Characteristics RX Signal Path (cont'd) Analog Signal Levels RX Audio Input Level LS/Ear Audio Output Level Path Gains/Levels RX Gain – 12H Nominal Adjustment Range Error of any Setting Volume – 12H Nominal Adjustment Range Step Size Error of any Setting Overall RX Distortion RX Hum and Noise SAT Signal Path Bandpass Filter Frequency Range Gain MX826 Preliminary Information See Note Min. Typ. Max. Unit 2 2 – – -7.0 0 – – dB dB 3.75 -0.2 – 9.70 0.2 dB dB -28.0 1.5 -1.0 2.0 – 0 2.5 1.0 dB dB dB – – -40.0 -40.0 -32.0 -34.0 dBp dB 5970 19.0 20.0 6030 21.0 Hz 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. © 1997 MX•COM Inc. www.mxcom.com Tele: 800 638-5577 910 744-5050 Fax: 910 744-5054 Doc. # 20480070.004 4800 Bethania Station Road, Winston-Salem, NC 27105-1201 USA All trademarks and service marks are held by their respective companies. AMPS/NAMPS System Audio Processor. MX826 Preliminary Information Package Outline Handling Precautions 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). The MX826 is a CMOS LSI circuit which includes input protection. However precautions should be taken to prevent static discharges which may cause damage. Fig.10 MX826DW 28-pin Small Outline I.C. Package A ➤ ➤ H D ➤ ➤ ➤ B ➤ C ➤ ➤ ➤ ➤ ➤ ➤ F ➤ ➤ G E ➤ ➤ ➤ Package Tolerances ➤ J ➤ M ➤➤ K ➤ ➤ L➤ ➤ ➤ ➤ ➤ N ➤ P R ➤ ➤ Fig.11 MX826J 28-pin Ceramic Dual In-Line Package A ➤ ➤ B ➤ ➤ D ➤ ➤ C ➤➤ E ➤ ➤ ➤ ➤ F G ➤ ➤ H ➤ ➤ ➤ ➤ ➤ Package Tolerances K ➤ ➤ ➤ ➤ J L © 1997 MX•COM Inc. www.mxcom.com Tele: 800 638-5577 910 744-5050 Fax: 910 744-5054 Doc. # 20480070.004 4800 Bethania Station Road, Winston-Salem, NC 27105-1201 USA All trademarks and service marks are held by their respective companies.