FX346LG

FX346 CMLMICRO | Alldatasheet

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CML Semiconductor Products PRODUCT INFORMATION FX346 AMPS, TACS, NMT Audio Processing Array Publication D/346/4 December 1991 Features/Applications Provisional Issue @ AMPS, TACS, NMT Audio + Data © SAT 4/6kHz Bandpass Filters Processing © 8/10kbit Rx Wideband Data Filter © Speech, SAT and Data — Full and Limiter Duplex Filtering @ Filters for Speech/FFSK, Pre/De-emphasis @ Speech Bandpass and Deviation . P' . Limiter Filters @ Input Gain Adjustment | rempout eowongge rreclivass ewes Ty AUDIO CHANNEL naew = =P > ae ‘SAT & WB DATA CHANNEL sxyguwout cal iu 940 Tone auteur sar AMP ‘usrER RY > ara wom oe | Eh woxanosencurgr FX346 “=e Rx AUDIO CHANNEL ween ~ eau ouTeyT Dat Pe MOIO + PS ROUT ieueaiel sea reoaraseron ourest tir t | i t Voo Veus Yes TAL mm SEE cnpenaate Fig.1 Internal Block Diagram srief Description The FX346 Audio Processing Array is a full-duplex The Rx SAT and Data Path consisting: ‘Speech, SAT and Data Processor designed to meet (i) A 13kHz wideband data filter and limiter. the composite specifications of AMPS, TACS and (ii) Switchable 6th order 4/6kHz SAT bandpass NMT 450/900. filter. - ; (i) 1200 baud FFSK signal data limiter on chip. The product in detail : All filter stages, excluding the Rx data paths, may be The Rx Audio Path consisting: de-powered for minimum current drain. () A 12th order lowpass fitter. Operation in AMPS/TACS or NMT mode is controlled (ii) A 4th order highpass fitter via a single logic input. (iii) Input gain adjustment and de-emphasis. The FX346, in combination with the FX009 Digitally a Controlled Ampiier Array and analogue switches The Tx Audio Path consisting: offers a complete speech and processing solution for (i) Separate 6th and 12th order lowpass filters. cellular radio. All filter sampling clocks are generated (ii) A 4th order highpass filter. ‘on-chip using an external 4.0MHz Xtal or clock pulse (ii) A linear deviation limiter. input. The FX346 is a low-power, single 5-volt device (iv) Input gain adjustment and pre-emphasis. available in 24-pin cerdip DIL or SMD plastic packages.

FX346J | FX346LG/LS 1 1 Xtal/Clock : The input to the clock oscillator circuitry. The clock oscillator components are on-chip and require only a single 4MHz Xtal or clock pulse input. Clock oscillations are maintained in “powersave” (Chip Enable = “0"). See Figure 2. 2 2 Xtal : The output of the clock oscillator circuitry. See Figure 2. 3 3 Chip Enable : The Chip Enable logic input. When a logic “0” the chip is put into a powersave mode, with only the minimum amount of monitoring circuitry enabled, to reduce current consumption. A logic “1” will enable all circuitry. This input operates in conjunction with the System Select input, signal paths are as shown in Table 1. 4 4 System Select : A logic input to select signal paths to either the AMPS/TACS or NMT specification. This input operates in conjunction with the Chip Enable input, signal paths are as shown in Table 1. Logic “1" = AMPS/TACS, logic “0” = NMT. 5 5 ‘Tx Amp Out : The “gain output” pin of the Transmit Audio Channel audio input amplifier. This output, together with the Tx Amp In pin is used, with external components, to set the required input gain/attenuation of this channel. See Figures 1 and 2, 6 6 Tx Amp In: The input pin to the Transmit Audio Channel. This inverting input, together with the Tx Amp Out pin is used, with external components, to set the required input gain/attenuation of the channel. See Figures 1 and 2. 7 7 Vous: The output of the on-chip analogue bias circuitry, internally set to V,./2 this pin requires to be decoupled to V,, with a capacitor, C,. Vas is maintained during “powersave" (Chip Enable = “0"). See Figure 2 and Table 1. 8 8 SAT Amp In: The input to the Supervisory Audio Tone (SAT) and Wideband Data Channel. This inverting input, together with the SAT Amp Out pin is used, with external components, to set the required input gain/attenuation of the channel. See Figures 1 and 2. 9 9 SAT Amp Out : The “gain output” pin of the Supervisory Audio Tone (SAT) and Wideband Data Channel. This pin, together with the SAT Amp In pin is used, with external components, to set the required input gain/attenuation of the channel. Attention is drawn to the data circuit sensitivity (Specification page). See Figures 1 and 2. 10 10 Rx Amp Out: The “gain output" pin of the Receive Audio Channel. This pin, together with the Rx Amp In pin is used, with external components, to set the required input gain/attenuation of the channel. See Figures 1 and 2. " 4 Rx Amp In: The input to the Receive Audio Channel. This inverting input, together with the Rx Amp Out pin is used, with external components, to set the required input gairvattenuation of the channel. See Figures 1 and 2.

FX346J |FX346LG/LS 12 12 Vg Negative supply rail (GND). 13 13 SAT Tone Out: The filtered Supervisory Audio Tone (SAT) output. AMPSITACS (-6dB) = 6kHz + 200Hz. NMT (-6d8) = 4kHz + 200Hz. 14 14 Fx Wideband Data Out : The filtered, limited, wideband data output. This data channel produces a limited rectangular wave output. Attention is drawn to the data circuit sensitivity ( Specification page). See Figures 1 and 2. 15 15 Limited SAT Tone Out : The filtered, limited Supervisory Audio Tone (SAT). Attention is drawn to the data circuit sensitivity ( Specification page). See Figures 1 and 2. | 16 16 Rx Audio Out : The bandpass filtered, de-emphasized audio output of the Rx Audio Channel. | 7 7 Rx Data Out : The de-emphasized, received data output. This data process may require filtering by low group delay filters before demodulation by modems such as : CML ~ FX419, FX429, FX439. 18 8 ‘Tx Audio Out : The processed audio to the transmission mixing and modulation circuitry. 19 19 ‘Tx Limiter Gain : The “gain output’ of the Tx Limiter Amplifier. This amplifier, using gain setting components, is used to produce the correct signal level for application to the Deviation Limiter. For limiter levels refer to the Specification page 6. Recommended circuitry is shown in Figure 2. 20 20 Tx Limiter In : The input to the Tx Limiter Amplifier. This input should be connected via external components to the Tx Pre-emphasis Out pin as shown in Figure 2. 24 21 ‘Tx Pre-emphasis Out : The output of the on-chip +6dB/octave pre-emphasis circuitry. This output should be connected to the Tx Limiter Amplifier via external components as shown in Figure 2. 22 22 ‘Tx Pre-emphasis In: The input to the on-chip transmitter pre-emphasis circuitry. This input would normally be connected to the output of an external audio compressor circuit. 23 23 ‘Tx Bandpass Out : The output of the first stage of bandpass filtering in the Transmit Audio Channel. This output will normally be connected to the input of an external audio compressor circuit. See Figures 1 and 2. 24 24 Voo : Positive supply rail. A single +5-volt power supply is required.

= & Vg x Ve is 1] xtavet0ck va xrat_| an |_TxBANDPASS OUT cu enaste || ap |o_TXPRE-EMPHASIS IN Rr system sevect | , ay | Pg ourunsisour Se _awpout_| , 20 Jo TELIMITER IN ia nano hem sag [cin — 6 1 Ry ¢, ® ia Fe Yous |, LG LS xe |_TxAvOIOOUT s yf wen | Rx DATAQUT — — 8 7 Sar Ano wel ° tg |_Bx AUDIO OUT to ag |_UMITED SAT TONE OUT AxAUDION [Tem |, ta |__WHDE BAND DATAOUT a, R, Nss_| 42 19 |_SATTONE OUT G Vss Fig.2 External Component Connections Component Value Notes Figure 2 shows the recommended components for use with the FX346. The notes below give component values and/or calculations. RYR,, RJR, RYR, RYR,. C,. Gain component combinations to set the gains of Feedback capacitor = 10.0pF. the Tx Audio, SAT and WB Data, Rx Audio and Limiter inputs. Cy Gain is calculated using the formula: Power supply decoupling capacitor = 1.0uF. Gain= R, C. — FEEDBACK Input coupling capacitor = 0.1pF. Rueur C,,C, and Co, — taking into account the effect of the parallel Input coupling capacitors = 1.0nF. feedback capacitor. Itis recommended that all gain resistor values are Component Tolerances kept above10kQ. Resistors + 10% cept above t Oko. Capacitors + 20% c,. Vaias decoupling capacitor = 1.0uF. To maintain low current consumption, Output Butters, anti-alias Clock Frequency Filters and input C,,C, and C,. internal pullup or pulldown resistors are not included Feedback capacitor values should be calculated ‘on-chip. (taking into account gain resistors R,, Ry, Ry, Res R, and R,) to give a -3dB point at approximately A noisy or badly regulated power supply can cause 18kHz for Rx and Tx Channel, this for anti-alias instability and/or variance of selected gains. filtering.

Application Information

Table 1 (below) shows the signal and data path condititons relevant to the System Select and Chip Enable inputs. Note that the oscillator circuitry and Va... line are enabled under all conditions. a 4MHz System Select Oscillator Veus Tx Audio | SAT Tone AMPS/TACS "1" Chip Enable = "1" Enabled Enabled Enabled | 6kHz, Enabled Enabled | cringnabo =o | Enatiod | Enabes | oiabied | atid | Enotes | diated | sade | NMT "oO" Chip Enable = "1" Enabled | cripznatio="o- | enabind | nate | oisbies | Dsabied | Diab | Oisabiea | craves | *able1 Signal Path Selection Figure 3 (below) demonstrates the possible audio and data functions performed by the FX346 Audio Processing Array when employed within the audio stages of either an NMT, AMPS or TACS mobile application. “ee ee | is ° eee! lovallpalal faa See ee ee ae Se pel a ey - ee oS ee Le ake 2 ae “ Bae a eae Gea | PAO46 SATA WO DATACHANNEL _ a Soc ee eee ee es oo ae sgn een cs seca oe OE es _ a = _ {pS oe i ap LPs -ALAUDIOCHANNE RT cerns eonton Fig.3 Example of FX346 Employed in the Audio Stages of a Typical NMT,AMPS or TACS Mobile Application

Exceeding the maximum rating can result in device damage. Operation of the device outside the operating limits is not implied. ‘Supply voltage 0.3 to 7.0V Input voltage at any pin (ref Veg = OV) -0.3 to (Voy + 0.3V) Sink/source current (supply pins) +/-30mA (other pins) +1 20mA Total device dissipation @ T,yy, 25°C 800mW Max. Derating tomwi°c Operating temperature range: FX346J -30°C to +85°C (cerdip) FX346LG/LS -30°C to +70°C (plastic) Storage temperature range: FX346J -55°C to +125°C (cerdip) FX346LG/LS -40°C to +85°C (plastic) Operating Limits All device characteristics are measured under the following conditions unless otherwise specified: Characteristics Note Min. Typ. Max. Unit Static Values | Supply Voltage (V9) 45 5.0 55 v Input Logic '1" 3 35 - - v Input Logic '0" 3 - - 15 v Supply Current — 6 | - Enabled - 12.0 - mA | = Disabled (Chip Enable = 0) - | ~ AMPS/TACS - 1.75 - mA -NMT - 15 - mA Impedance ‘Audio Amplifier input/s 10.0 - - Ma ‘Audio Op-Amp Output/s - 6.0 10.0 ka ‘Audio Output - - 10.0 KQ Digital Inputs 100 1000 - Ka Digital (data) Output/s - 6.0 10.0 kQ Dynamic Values Xtal/Clock Frequency - 4.0 - MHz Input Amplifier Gain/s - - 40.0 a8 Tx Audio Channel Audio Input Level 1 - 300 - mVrms Overall Gain 1,7,8 - ) - 0B Deviation Limiter Levels 3,5 1.0 4.0 v Bandpass Frequency Range (-3d8) 8 300 3400 Hz Pre-emphasis - ~ Passband 300 3400 Hz — Response - 6.0 - dBioctave ~ Gain at 1kHz - 0 - 3B ~ Passband Deviation from Ideal 1.0 - 1.0 0B Channel Stopband Attenuation — < 160Hz - 25 - 3B 2 5500Hz - 40.0 - a8 Output Noise 2 - 1.50 - mVrms

Specification... | Characteristics Note Min. Typ. Max. Unit SAT and Wideband Data Channel Input Level 1 - 300 - mVrms Data Limiter Sensitivity 1,10 ~ Limited SAT Tone (4kHz & 6kHz) - 10 - mVrms - Wideband Data - 20 - mVrms 13kHz Lowpass Filter — | ~ Passband (-3dB) - - 15.0 kHz | — Passband Gain (100Hz — 13kHz) “1.0 - +1.0 Ci) ~ Passband Ripple (100Hz — 13kHz) - 2.0 - aB ~ Stopband Attenuation (2 25kHz) - 30.0 - 3B SAT Bandpass Filter - NMT 4kHz — 4,9 — Passband Frequency Range (-6dB) 3800 4200 Hz — Passband Gain - 15 - 6B — Passband Ripple (4kHz + 55Hz) - - 2.0 oB | = Stopband Attenuation (<2kHz, >6kHz) 35.0 37.0 - ¢B — Output Noise 2 - 10.0 - mVrms — Aliasing Frequency 50.0 - - kHz AMPS/TACS 6kHz — 9 ~ Passband Frequency Range (-6dB) 5800 - 6200 Hz ~ Passband Gain - 12.0 - dB ~ Passband Ripple (6kHz + 55Hz) - 2.0 3.0 aB — Stopband Attenuation (<4kHz, >8kHz) - 35.0 - 3B — Output Noise 2 - 75 - m\\vrms | Rx Audio Channel | Input Level (Rx Audio, Rx Data) 1 - 300 - mVrms | Gain 1,78 - 0 - a8 Passband Frequency Range (-3dB) 4 260 3400 Hz Output Noise 2 - 15 - mVvrms Rx Data Channel De-emphasis (Audio and Data) — - Passband 300 3400 Hz — Response - -6.0 - dB/octave ~ Gain at 1kHz - 0 - 3B — Passband Deviation from Ideal 1.0 - +10 «8B Notes 1, With the Input Op-Amp gains at unity 2. Measured at the output with the channel input a.c. short circuit. 3. These levels are referenced to V,, and in this case measured with V,. = 5.0 volts. 4. Specified over the full operating voltage and temperature range. 5. Limiter input at Vays. 6. To maintain low current consumption, buffers and clock filters are not included on-chip in series with outputs. 7. Input frequency 1.0kHz. 8. With no pre-/de-emphasis effect. 9. Shows the SAT Tone Output specification in the selected mode. 10. The minimum level at the SAT Amp Input to produce a valid logic output.

Figure 4. The 'LG' version is shown in Figure 5 _includes input protection. However To allow complete identification, the 'LG' and discharges which may cause damage.