Ordering number: EN 3852D Monolithic Linear IC LA2806M Signal Processor and Power Amplifier IC for Telephone Answering Machines Overview Package Dimensions The LA2806M is a one-chip voice signal processing IC for single-mechanism answering machines that incorporates the basic functions required for an answering machine as well as the microcontroller interface and analog switches that are needed in order to control those basic functions. unit : mm 3073A-MFP30S [LA2806M] Functions . Recording preamplifier (with ALC : LINE/MIC input) . Playback equalizer amplifier . Recording amplifier (DC bias) . Analog switches . Voice-operated switch (VOX) with filter . Power amplifier (P = 200 mW, R = 8 Ω, V = 5 V) . Line output buffer . Microcontroller interface O L CC SANYO : MFP30S Features . One-chip voice signal processing for single-mechanism machines . answering Because the LA2806M incorporates all of the basic functions . . . . required for an answering machine and can be controlled by a microcontroller, this IC makes it possible to design an original system Built-in power amplifier Allows conversation recording mode Recording bias and amplifier gain control current can be set separately using external resistors. Small package (MFP30S) Specifications Maximum Ratings at Ta = 25°C Parameter Maximum supply voltage Allowable power dissipation Symbol VCC max, P.VCC max Pd max Conditions Ratings Unit 9 800 V mW Operating temperature Topr –20 to +70 °C Storage temperature Tstg –40 to +150 °C SANYO Electric Co.,Ltd. Semiconductor Bussiness Headquarters TOKYO OFFICE Tokyo Bldg., 1-10, 1 Chome, Ueno, Taito-ku, TOKYO, 110 JAPAN O3097HA (II)/72495HA (ID)/3092HK/D111TS No.3852 - 1/11 LA2806M Operating Conditions at Ta = 25°C Parameter Symbol Recomended supply voltage Conditions Ratings VCC, P.VCC Operating supply voltage range VCC op, P.VCC op Recommended load resistance RL Preamplifier input voltage VIN Unit 5 V 4.5 to 7.5 V 8 Ω Power amplifier 0 to 1.0 Vp-p Operating Characteristics at Ta = 25°C, VCC = 5 V, f = 1 kHz Parameter Quiescent current [Preamplifier] Symbol ICC Voltage gain VGC Total harmonic distortion THD ALC turnover input voltage VALC ALC output saturation voltage VOS Equivalent input noise voltage VNI ALC range ALC W Conditions –70 dBV input, measured between pins 5 and 8 –40 dBV input, measured between pins 5 and 8 Measured between pins 5 and 8 –40 dBV input, measured between pins 5 and 8 Input short circuited (internal 2.2 kΩ resistance) From ALC ON to THD = 1 % min typ 10 max 15 Unit mA 59 61 dB 0.5 1.0 % –68 –64 –60 dBV 400 500 625 mVrms 1.5 5.0 µVrms 57 40 45 dB 57 59 61 dB 0.5 1.5 % 1.5 5.0 µVrms –7.0 –4.0 –1.0 dB 0.4 0.8 1.2 V 0.5 1.0 % 0 +1 dB [Playback equalizer amplifier] Voltage gain VGE Total harmonic distortion THD Equivalent input noise voltage VNI –70 dBV input, measured between pins 2 and 8 –60 dBV input, measured between pins 2 and 8 Input short circuited (internal 2.2 kΩ resistance), Flat [Recording amplifier] Voltage gain Output bias voltage Total harmonic distortion [LINE amplifier]: RL = 1 kΩ Voltage gain Maximum output voltage VGR VB THD VGL VO max Total harmonic distortion THD [Power amplifier]: RL = 8 kΩ, input pin 20 Voltage gain Output voltage Total harmonic distortion Input resistance Ripple rejection ratio Output noise voltage [Voice-operated switch] Pin 25, R Sensitivity Output ON voltage [Control pin voltage] Pin 26 to 30 VGP PO 50 kΩ impedance connected to pin 1 ZAC, measured between pins 10 and 2 100 kΩ resistance connected to pin 1 ZDC, measured on pin 2 –40 dBV preamplifier input Measured between pins 10 and 22 Measured between pins 10 and 22, THD = 1 % –30 dBV input, measured between pins 20 and 17 THD = 10 % VH Input high-level voltage VL Input low-level voltage Input high-level voltage, supplied via diode VH [VREF] Output voltage VREF 0.6 –40 dBV preamplifier input THD PO = 100 mW ri SVRR Rg = 0, fr = 100 Hz, VCCr = –20 dBV VNO Input short circuited, Flat = 20 kΩ applied 5 V. VOXL –23 dBV input, f = 800 Hz VOXH –27 dBV input, f = 800 Hz V sat 2 V supplied to pin24 Pin 24 (MUTE) –1 Vrms 0.5 1.0 % 26 28 30 dB 0.2 0.25 10 40 0.5 15 50 0.1 W 1.0 20 0.5 0.3 4.5 5.0 0.3 % kΩ dB mVrms V V V 1.5 (or VCC + 0.3) 0 0.8 V 1.5 VCC–0.7 V 2.45 V 2.05 V 2.25 No. 3852 - 2/11 Allowable power dissipation, Pd max – mW LA2806M Pd max – Ta Recommended mounting Independent IC Ambient temperature, Ta – °C Equivalent Block Diagram No. 3852 - 3/11 LA2806M Test Circuit Unit (resistance: Ω, capacitance: F) No. 3852 - 4/11 LA2806M Mode Selection REC ON/ OFF LINE PWR ON/ ON/ OFF OFF × HIGH HIGH HIGH HIGH LOW LOW LOW LOW LOW LOW LOW LOW LOW × LOW LOW LOW HIGH HIGH LOW LOW LOW HIGH LOW HIGH LOW HIGH Mode MUTE ICM REC 2WAY REC DICT REC 2WAY BEEP ICM OUT ICM PLAY OGM REC OGM CHANGE OGM OUT OGM PLAY ROOM MONI ROOM OUT VOICE SELE Conversation recording × HIGH LOW LOW HIGH HIGH HIGH LOW HIGH HIGH HIGH LOW HIGH HIGH INPUT MUTE D1 D0 × HIGH HIGH HIGH LOW LOW LOW HIGH HIGH LOW LOW HIGH HIGH HIGH × HIGH HIGH LOW HIGH LOW LOW LOW HIGH HIGH HIGH LOW HIGH HIGH HIGH LOW LOW LOW LOW LOW LOW LOW LOW LOW LOW LOW LOW LOW HIGH HIGH HIGH HIGH HIGH LOW SW1/ SW2 SW11 SW3 ICM ICM LINE PLAY REC × × × 1 0 1 1 0 1 1 0 0 1 0 1 0 1 0 0 1 0 0 0 0 0 0 1 0 0 1 0 0 1 0 0 0 0 0 1 0 0 1 1 0 1 SW10 SW6 SW7 SW8 SW9 SW4 SW5 PRE/ PRE/ MONI LINE PWR MIC MUTE OGM /OGM EQ × 0 0 1 0 0 0 1 0 0 0 1 0 0 0 1 1 1 1 1 1 1 1 1 1 1 1 1 × 1 1 1 0 1 1 1 1 0 0 1 1 1 × 1 1 1 1 1 1 1 1 1 1 1 1 0 × 0 0 0 1 1 0 0 0 1 0 1 0 1 × 1 0 0 1 1 1 0 1 1 1 0 1 1 × 0 0 0 0 1 1 0 0 0 0 0 0 0 0 1 1 0 1 1 0 Notes 2WAY BEEP : LINE OUT –6 dB 1 = ON and 0 = OFF (SW1 to SW5, SW8, SW9 and SW11) Pin Functions Pin No. Pin name 1 BIAS/GAIN 2 ICM 3 PB NF 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 GND LINE MIC PRE NF PRE OUT ALC. CT SIG IN OGM/BEEP FIL NF FIL OUT V. REF VCC P.GND PWR OUT P.VCC D.C PWR IN PWR MONI LINE OUT 23 TH 24 25 26 27 28 29 30 VOX. C/MUTE VOX D0 D1 PWR ON/OFF LINE ON/OFF REC ON/OFF Functions Bias. Recording amplifier gain and recording bias current controled by external resistor. Incoming head input/output Playback amplifier feedback. Receives negative feedback input from PRE OUT (pin 8). Preamplifier ground Line input Microphone input Preamplifier feedback. Receives negative feedback input from PRE OUT (pin 8). Preamplifier/playback amplifier output Automatic level control time constant adjust input Preamplifier/playback amplifier output signal input Outgoing message/beep input Filter amplifier negative feedback input Filter amplifier output Internal reference voltage output (Approx. 2.2 V) Preamplifier supply Power amplifier ground Power amplifier output Power amplifier supply Power amplifier reference voltage output (Approx. 4/9 x P.VCC) Power amplifier input Power amplifier monitor output Line amplifier output Voice-operated switch (VOX) threshold adjust input. VOX sensitivity can be adjusted by connecting this signal to the VREF pin (pin 14) via a resistor. Voice-operated switch (VOX) detection and mute control Voice-operated switch (VOX) open-collector output Incoming message, line, microphone and outgoing message/beep analog switch control inputs. Power amplifier ON/OFF analog switch control input Line amplifier ON/OFF analog switch control input Recording amplifier ON/OFF analog switch control input No. 3852 - 5/11 LA2806M IC Usage Notes 1) Control Inputs (pin 26 to 30) Each control input is connected to VREF through a 100 kΩ resistance. The control input threshold level is VREF × 3/5. 2) Automatic Level Control (ALC) The automatic level control circuit operates when the input signal is in the range between –64 dBV to –20 dBV. The output saturation level is 500 mV rms. 3) Mute Circuit (pin 24) The VOX. C/MUTE input controls the mute function. When it goes HIGH, analog switch SW5 opens, switching off the power amplifier. The power amplifier output goes high impedance and VOX (pin 25) goes LOW. 4) V/I Conversion V/I conversion is performed in order to extract the recording current for DC bias. The conversion gain and the bias current can be controlled by an external resistor connected to pin 1, and current that is equal to the pin 1 output current is output on pin 2. 5) Playback Amplifier and Preamplifier Feedback Resistance As the playback amplifier and preamplifier employ a zero-bias method, the amplifier’s output DC level (VODC) is determined by the feedback resistance (RNF) and the NF pin sink current (Ii = 15 µA). VODC = VBE + RNF × Ii VBE 6 0.7 V A feedback resistance of 100 kΩ is recommended for both the playback amplifier and the preamplifier to provide an output DC level with sufficient output dynamic range. 6) Filter amplifier A bandwidth-limiting filter is provided to restrict the VOX circuit input frequency. It can also be used as an inverting amplifier. It has a center frequency of 800 Hz, a gain of 2 and a Q factor of 1. 7) Voice-operated Switch (VOX) This switch detects whether anyone is speaking or not by detecting the level of the signal (V13) on the filter amplifier output pin (pin 13). V13 % –18 dBV ... Pin 25 low The detection level is adjusted by inserting resistor R between TH (pin 23) and VREF (pin 14). Refer to the diagram below. Unit (resistance: Ω, capacitance: F) No. 3852 - 6/11 LA2806M Sample Applications of Operating Modes 1) 2) 3) 4) ICM REC (In coming message recording) Recording incoming messages. Memo recording from a remote location (remote control). . . 2WAY REC (Two-way recording) .Simultaneously recording conversations. . Recording incoming messages. DICT REC (Dictaphone) . Recording messages using the microphone input (Recording short messages to your family, etc.). 2WAY BEEP (Two-way beep) . The alarm sound is output on the speaker and is recorded as an incoming message. At the same time, it is output on the line the calling party. . toIndicates that the incoming message is being recorded. . The line output tone is 6 dB lower than the output level in other modes. 5) ICM OUT (Incoming message output) Playing back incoming messages locally. Playing back incomming messages from a remote location. Transferring incoming messages. Playing back dictaphone recordings. 6) ICM PLAY (Incoming message playback) Playing back incoming messages. Playing back dictaphone messages. 7) 8) 9) 10) 11) 12) . . . . . . OGM REC (Outgoing message recording) . Recording outgoing messages. Messages can be transferred under microcomputer control to integrated memory devices. OGM CHANGE (Remote outgoing message recording) Re-recording outgoing messages from a remote location. . OGM OUT (Outgoing message output) . Playing back outgoing messages locally. . Playing back outgoing messages from a remote location. OGM PLAY (Outgoing message playback) . Playing back and confirming outgoing messages. ROOM MONI (Remote microphone monitoring) . Monitoring microphone input from a remote location. ROOM OUT (Remote speaker output) . Output messages through the loudspeaker from a remote location. 13) VOICE SELE (Voice monitoring) Sending output messages, and at the same time monitoring the caller’s voice through the loudspeaker. 14) . Conversation REC (Conversation recording) . Simultaneously recording incoming messages and playing back the outgoing message. IC Usage Notes 1) Printed Circuit Board When designing a printed circuit board, the GND line connected to pin 4 should be thick and short. Common impedance may lead to additional distortion. 2) Power Amplifier Polyester film capacitors should be used as the oscillation prevention capacitor betweeen output pin 17 and GND, as they have better temperature and frequency characteristics than electrolytic capacitors. Alminium electrolytic capacitors and ceramic capacitors may cause oscillation at low temperatures. 3) Switching Noise Switching noise can be eliminated by applying a LOW-level pulse greater than 10 ms to PWR ON/OFF pin 28 while the preamplifier is being switched. No. 3852 - 7/11 LA2806M 4) If the IC is used near the maximum ratings, even a slight variation in conditions may cause the maximum ratings to be exceeded, thereby leading to breakdown. Allow an ample margin of variation for supply voltage etc. and use the IC in the range where the maximum ratings are not exceeded. exceeded. 5) Short Circuits Between Pins The circuit board should be examined for short circuits between pins before initial power-up to prevent damage to the device when voltage is applied. 6) Short-circuit Load Short circuiting the LA2806M output for an extended period while the power is on can damage the device. 7) Playback Amplifier and Preamplifier Feedback Resistance As the playback amplifier and preamplifier employ a zero-bias method, the amplifier’s output DC level (VODC) is determined by the feedback resistance (RNF) and the NF pin sink current (Ii = 15 µA). VODC = VBE + RNF × Ii VBE 6 0.7 V A feedback resistance of 100 kΩ is recommended for both the playback amplifier and the preamplifier to provide an output DC level with sufficient output dynamic range. No. 3852 - 8/11 LA2806M Sample Application Circuit CPU No. 3852 - 9/11 LA2806M ICC – VCC, P.VCC ALC Characteristic, Distortion Total harmonic distortion, THD – % Output level – mVrms Quiescent current, ICC – mA Preamplifer LINE input (ICM REC) Voltage gain, VGO – dB Preamplifier Input level – dBV VNI – VCC Equivalent input voltage, VNI – µVrms Supply voltage, VCC, P.VCC – V VGO – f Supply voltage, VCC – V Frequency, f – Hz Input/Output Characteristic, Distortion Input frequency, f – Hz PO – P.VCC Supply voltage, P.VCC – V Pin 10 input level – dBV THD – PO Total harmonic distortion, THD – % Output power, PO – mW Power Amplifier Line Amp ICM OUT f = 1 kHz RL = 1kΩ Input SIG IN VCC = 5 V Total harmonic distortion, THD – % PB EQ Amplifier ICM PLAY Input –60 dBV VCC = 5 V Total harmonic distortion, THD – % Pin 22 output level – mVrms VGE, THD – f Voltage gain, VGE – dB Line Input (ICM REC) Input Short Preamplifier Power Amplifier Output power, PO – mW No. 3852 - 10/11 LA2806M VNO – P.VCC Power Amplifier Power Amplifier Output noise voltage, VNO – µVrms Supply voltage Ripple rejection ratio, SVRR – dB SVRR – P.VCC Supply voltage, P.VCC – V VOX Sensitivity Characteristic Pin 22 output level – mVrms Total harmonic distortion, THD – % Filter amp input level – dBV Supply voltage, P.VCC – V OGM Input/Output Characteristic, Distortion Frequency, f – Hz Reference voltage, VREF – V Pin 11 input level – dBV VREF – VCC Supply voltage, VCC – V No products described or contained herein are intended for use in surgical implants, life-support systems, aerospace equipment, nuclear power control systems, vehicles, disaster/crime-prevention equipment and the like, the failure of which may directly or indirectly cause injury, death or property loss. Anyone purchasing any products described or contained herein for an above-mentioned use shall: 1 Accept full responsibility and indemnify and defend SANYO ELECTRIC CO., LTD., its affiliates, subsidiaries and distributors and all their officers and employees, jointly and severally, against any and all claims and litigation and all damages, cost and expenses associated with such use: 2 Not impose any responsibility for any fault or negligence which may be cited in any such claim or litigation on SANYO ELECTRIC CO., LTD., its affiliates, subsidiaries and distributors or any of their officers and employees jointly or severally. Information (including circuit diagrams and circuit parameters) herein is for example only; it is not guaranteed for volume production. SANYO believes information herein is accurate and reliable, but no guarantees are made or implied regarding its use or any infringements of intellectual property rights or other rights of third parties. This catalog provides information as of October, 1997. Specifications and information herein are subject to change without notice. No. 3852 - 11/11