SSM2135

a FEATURES Excellent Sonic Characteristics High Output Drive Capability 5.2 nV/√Hz Equivalent Input Noise @ 1 kHz 0.001% THD+N (VO = 2.5 V p-p @ 1 kHz) 3.5 MHz Gain Bandwidth Unity-Gain Stable Low Cost APPLICATIONS Multimedia Audio Systems Microphone Preamplifier Headphone Driver Differential Line Receiver Balanced Line Driver Audio ADC Input Buffer Audio DAC l-V Converter and Filter Pseudo-Ground Generator Dual Single-Supply Audio Operational Amplifier SSM2135 PIN CONNECTIONS 8-Lead Narrow-Body SOIC (S Suffix) OUT A –IN A +IN A V–/GND 8-Lead Epoxy DIP (P-Suffix) 1 2 3 4 8 7 6 5 V+ OUT B –IN B +IN B OUT A –IN A +IN A V–/GND V+ SSM2135 OUT B –IN B +IN B SSM2135 under moderate load conditions. Under severe loading, the SSM2135 still maintains a wide output swing with ultralow distortion. Particularly well suited for computer audio systems and portable digital audio units, the SSM2135 can perform preamplification, headphone and speaker driving, and balanced line driving and receiving. Additionally, the device is ideal for input signal conditioning in single-supply sigma-delta analogto-digital converter subsystems such as the AD1878/AD1879. The SSM2135 is available in 8-lead plastic DIP and SOIC packages, and is guaranteed for operation over the extended industrial temperature range of –40°C to +85°C. *Protected by U. S. Patent No. 5,146,181. GENERAL DESCRIPTION The SSM2135 Dual Audio Operational Amplifier permits excellent performance in portable or low power audio systems, with an operating supply range of +4 V to +36 V or ± 2 V to ± 18 V. The unity gain stable device has very low voltage noise of 4.7 nV/√Hz, and total harmonic distortion plus noise below 0.01% over normal signal levels and loads. Such characteristics are enhanced by wide output swing and load drive capability. A unique output stage* permits output swing approaching the rail FUNCTIONAL BLOCK DIAGRAM V+ +IN 9V 9V –IN OUT V–/GND REV. D Information furnished by Analog Devices is believed to be accurate and reliable. However, no responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of Analog Devices. One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. Tel: 617/329-4700 Fax: 617/326-8703 SSM2135–SPECIFICATIONS Parameter AUDIO PERFORMANCE Voltage Noise Density Current Noise Density Signal-To-Noise Ratio Headroom Total Harmonic Distortion Symbol en in SNR HR THD+N (VS = +5 V, –40 C < TA < +85 C unless otherwise noted. Typical specifications apply at TA = +25 C.) Min Typ 5.2 0.5 121 5.3 0.003 0.005 0.6 0.9 3.5 5.8 +4.0 2.0 750 50 Max Units nV/√Hz pA/√Hz dBu dBu % % V/µs MHz µs V mV nA nA MΩ dB V/µV V V mV mV mA V V dB mA mA Conditions f = 1 kHz f = 1 kHz 20 Hz to 20 kHz, 0 dBu = 0.775 V rms Clip Point = 1% THD+N, f = 1 kHz, RL = 10 kΩ AV = +1, VO = 1 V p-p, f = 1 kHz, 80 kHz LPF RL = 10 kΩ RL = 32 Ω RL = 2 kΩ, TA = +25°C to 0.1%, 2 V Step DYNAMIC PERFORMANCE Slew Rate Gain Bandwidth Product Settling Time INPUT CHARACTERISTICS Input Voltage Range Input Offset Voltage Input Bias Current Input Offset Current Differential Input Impedance Common-Mode Rejection Large Signal Voltage Gain SR GBW tS VCM VOS IB IOS ZIN CMR AVO 0 VOUT = 2 V VCM = 0 V, VOUT = 2 V VCM = 0 V, VOUT = 2 V 0 V ≤ VCM ≤ 4 V, f = dc 0.01 V ≤ VOUT ≤ 3.9 V, RL = 600 Ω RL = 100 kΩ RL = 600 Ω RL = 100 kΩ RL = 600 Ω 87 2 4.1 3.9 ± 30 +4 ±2 90 0.2 300 4 112 OUTPUT CHARACTERISTICS Output Voltage Swing High VOH Output Voltage Swing Low Short Circuit Current Limit POWER SUPPLY Supply Voltage Range Power Supply Rejection Ratio Supply Current VOL ISC VS PSRR ISY 3.5 3.0 Single Supply Dual Supply VS = +4 V to +6 V, f = dc VOUT = 2.0 V, No Load VS = +5 V VS = ± 18 V, VOUT = 0 V, No Load +36 ± 18 120 2.8 3.7 6.0 7.6 ABSOLUTE MAXIMUM RATINGS THERMAL CHARACTERISTICS Supply Voltage Single Supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . +36 V Dual Supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ± 18 V Input Voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ± VS Differential Input Voltage . . . . . . . . . . . . . . . . . . . . . . . . 10 V Output Short Circuit Duration . . . . . . . . . . . . . . . . Indefinite Storage Temperature Range . . . . . . . . . . . . –65°C to +150°C Operating Temperature Range . . . . . . . . . . . –40°C to +85°C Junction Temperature Range (TJ) . . . . . . . . –65°C to +150°C Lead Temperature (Soldering, 60 sec) . . . . . . . . . . . . +300°C ESD RATINGS Thermal Resistance1 8-Lead Plastic DIP 8-Lead SOIC 1 θJA θJC θJA θJC 103°C/W 43°C/W 158°C/W 43°C/W θJA is specified for worst case conditions, i.e., θJA is specified for device in socket for P-DIP and device soldered in circuit board for SOIC package. ORDERING GUIDE 883 (Human Body) Model . . . . . . . . . . . . . . . . . . . . . . . 1 kV EIAJ Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 175 V Model SSM2135P SSM2135S Temperature Range –40°C to +85°C –40°C to +85°C Package Description Package Option 8-Lead Plastic DIP N-8 8-Lead SOIC SO-8 –2– REV. D SSM2135 +5V 500µF + 10 VS = +5V AV = +1, ƒ = 1kHz VIN = 1Vp-p 1 RL RL = 10kΩ WITH 80kHz FILTER THD – % +2.5Vdc 0.1 Figure 1. Test Circuit for Figures 2–4 0.01 0.001 10 100 1k LOAD RESISTANCE – Ω 10k Figure 4. THD+N vs. Load (See Test Circuit) 1 VS = +5V RL = 100kΩ VOUT = 2.5Vp-p ƒ = 1kHz WITH 80kHz FILTER NONINVERTING 0.1 THD+N – % INVERTING Figure 2. THD+N vs. Amplitude (See Test Circuit; AV = +1, VS = +5 V, f = 1 kHz, with 80 kHz Low-Pass Filter) 0.01 0.001 0 10 20 30 GAIN – dB 40 50 60 Figure 5. THD+N vs. Gain 1 VS = +5V AV = +1, ƒ = 1kHz VIN = 1Vp-p RL = 10kΩ 0.1 WITH 80kHz FILTER THD+N – % Figure 3. THD+N vs. Frequency (See Test Circuit; AV = +1, VIN = 1 V p-p, with 80 kHz Low-Pass Filter) 0.01 0.001 5 10 15 20 25 30 SUPPLY VOLTAGE – V Figure 6. THD+N vs. Supply Voltage REV. D –3– SSM2135 5 VS = +5V TA = +25 °C 4 in – pA/ √Hz 3 2 1 0 1 10 100 FREQUENCY – Hz 1k Figure 7. SMPTE Intermodulation Distortion (AV = +1, VS = +5 V, f = 1 kHz, RL = 10 kΩ) Figure 10. Current Noise Density vs. Frequency 1s 100 90 10 0% Figure 8. Input Voltage Noise (20 nV/div) Figure 11. Frequency Response (AV = +1, VS = +5 V, VIN = 1 V p-p, RL = 10 kΩ) 30 VS = +5V TA = +25 °C 100 90 25 20 en – nV/ √Hz 15 10 10 0% 5 500m V 1 µS 0 1 10 100 FREQUENCY – Hz 1k Figure 9. Voltage Noise Density vs. Frequency Figure 12. Square Wave Response (VS = +5 V, AV = +1, RL = ∞) –4– REV. D SSM2135 60 40 CHANNEL SEPARATION – dB 50 VS = +5V TA = +25°C CLOSED-LOOP GAIN – dB VS = +5V 40 AV = +100 30 TA = +25 °C 20 0 –20 –40 –60 –80 –100 –120 105 20 AV = +10 10 0 AV = +1 –10 –20 10 100 1k 10k 100k FREQUENCY – Hz 1M 10M 1k 10k 100k FREQUENCY – Hz 1M 10M Figure 13. Crosstalk vs. Frequency (RL = 10 kΩ) Figure 16. Closed-Loop Gain vs. Frequency 140 VS = +5V COMMON-MODE REJECTION – dB 120 100 TA = +25° C 100 VS = +5V 80 OPEN-LOOP GAIN – dB TA = +25 °C 0 GAIN 80 40 PHASE 20 θm = 57° 90 60 40 135 20 0 100 0 180 –20 1k 10k FREQUENCY – Hz 100k 1M 1k 10k 100k FREQUENCY – Hz 1M 225 10M Figure 14. Common-Mode Rejection vs. Frequency 140 120 100 PSRR – dB Figure 17. Open-Loop Gain and Phase vs. Frequency 50 VS = +5V AV = +1 TA = +25 °C OVERSHOOT – % 45 40 35 30 25 20 15 VS = +5V RL = 2kΩ VIN = 100mVp–p TA = +25 °C AV = +1 80 60 40 20 –PSRR +PSRR NEGATIVE EDGE POSITIVE EDGE 10 0 –20 10 100 1k 10k FREQUENCY – Hz 100k 1M 5 0 0 100 200 300 400 500 LOAD CAPACITANCE – pF Figure 15. Power Supply Rejection vs. Frequency Figure 18. Small Signal Overshoot vs. Load Capacitance REV. D –5– PHASE – Degrees 60 45 SSM2135 50 45 40 OUTPUT VOLTAGE – Volts 30 25 20 15 10 5 40 VS = +5V TA = +25 °C 35 35 IMPEDANCE – Ω 30 25 20 15 10 5 AVCL = +100 VS = +5V AV = +1 RL = 10k ƒ = 1 kHz THD+N = 1% TA = +25 °C AVCL = +10 AVCL = +1 0 10 100 1k 10k FREQUENCY – Hz 100k 1M 0 0 5 10 15 20 25 30 SUPPLY VOLTAGE – Volts 35 40 Figure 19. Output Impedance vs. Frequency Figure 22. Output Swing vs. Supply Voltage 5 VS = +5V TA = +25 °C AV = +1 ƒ = 1 kHz THD+N = 1% 5.0 VS = +5.0V 2.0 4 MAXIMUM OUTPUT – Volts 4.5 +SWING RL = 2kΩ 4.0 1.5 3 2 +SWING RL = 600Ω –SWING RL = 2kΩ 1.0 3.5 –SWING RL = 600Ω 3.0 0.5 1 0 1 10 100 1k LOAD RESISTANCE – Ω 10k 100k –75 –50 –25 0 25 50 75 100 0 125 TEMPERATURE – °C Figure 20. Maximum Output Voltage vs. Load Resistance Figure 23. Output Swing vs. Temperature and Load 6 VS = +5V MAXIMUM OUTPUT SWING – Volts 5 RL = 2kΩ TA = +25 °C AV = +1 SLEW RATE – V/µs 2.0 VS = +5V +0.5V ≤ V OUT ≤ +4.0V 1.5 +SLEW RATE 4 3 1.0 –SLEW RATE 2 0.5 1 0 1k 10k 100k FREQUENCY – Hz 1M 10M 0 –75 –50 –25 0 25 50 75 100 125 TEMPERATURE – °C Figure 21. Maximum Output Swing vs. Frequency Figure 24. Slew Rate vs. Temperature –6– REV. D NEGATIVE OUTPUT SWING – Volts POSITIVE OUTPUT SWING – Volts SSM2135 20 18 16 VS = +5.0V VO = 3.9V 5 4 RL = 2kΩ OPEN-LOOP GAIN – V/µV SUPPLY CURRENT – mA 14 12 10 8 6 4 2 0 –75 –50 –25 VS = ±18V 3 VS = ±15V VS = +5.0V RL = 600Ω 2 1 0 0 25 50 75 100 125 –75 –50 –25 0 25 50 75 100 125 TEMPERATURE – °C TEMPERATURE – °C Figure 25. Open-Loop Gain vs. Temperature Figure 27. Supply Current vs. Temperature 70 VS = +5V 5 500 GAIN-BANDWIDTH PRODUCT – MHz 65 GBW 60 θm 4 INPUT BIAS CURRENT – nA 400 VS = +5.0V 300 VS = ±15V 200 PHASE MARGIN – Degrees 3 55 2 100 50 –75 –50 –25 0 25 50 75 100 TEMPERATURE – °C 1 125 0 –75 –50 –25 0 25 50 75 100 125 TEMPERATURE – °C Figure 26. Gain Bandwidth Product and Phase Margin vs. Temperature Figure 28. Input Bias Current vs. Temperature APPLICATION INFORMATION The SSM2135 is a low voltage audio amplifier that has exceptionally low noise and excellent sonic quality even when driving loads as small as 25 Ω. Designed for single supply use, the SSM2135’s inputs common-mode and output swing to zero volts. Thus with a supply voltage at +5 V, both the input and output will swing from 0 V to +4 V. Because of this, signal dynamic range can be optimized if the amplifier is biased to a +2 V reference rather than at half the supply voltage. The SSM2135 is unity-gain stable, even when driving into a fair amount of capacitive load. Driving up to 500 pF does not cause any instability in the amplifier. However, overshoot in the frequency response increases slightly. The SSM2135 makes an excellent output amplifier for +5 V only audio systems such as a multimedia workstation, a CD output amplifier, or an audio mixing system. The amplifier has large output swing even at this supply voltage because it is designed to swing to the negative rail. In addition, it easily drives load impedances as low as 25 Ω with low distortion. The SSM2135 is fully protected from phase reversal for inputs going to the negative supply rail. However, an internal ESD protection diodes will turn “on” when either input is forced more than 0.5 V below the negative rail. Under this condition, input current in excess of 2 mA may cause erratic output behavior, in which case a current limiting resistor should be included in the offending input if phase integrity is required with excessive input voltages. A 500 Ω or higher series input resistor will prevent phase inversion even with the input pulled 1 volt below the negative supply. “Hot” plugging the input to a signal generally does not present a problem for the SSM2135, assuming the signal does not have any voltage exceeding the device’s supply voltage. If so, it is advisable to add a series input resistor to limit the current, as well as a Zener diode to clamp the input to a voltage no higher than the supply. REV. D –7– SSM2135 APPLICATION CIRCUITS A Low Noise Microphone Preamplifier A Low Noise Stereo Headphone Driver Amplifier Figure 29 shows the SSM2135 used in a stereo headphone driver for multimedia applications with the AD1848, a 16-bit stereo codec. The SSM2135 is equally well suited for the serialbused AD1849 stereo codec. The headphone’s impedance can be as low as 25 Ω, which covers most commercially available high fidelity headphones. Although the amplifier can operate at up to ± 18 V supply, it is just as efficient powered by a single +5 V. At this voltage, the amplifier has sufficient output drive to deliver distortion-free sound to a low impedance headphone. LOUT VCC GND VREF 40 35/36 34/37 10kΩ +5V 0.1µF 2 1 3 8.66kΩ 470µF The SSM2135’s 4.7 nV/√Hz input noise in conjunction with low distortion makes it an ideal device for amplifying low level signals such as those produced by microphones. Figure 31 illustrates a stereo microphone input circuit feeding a multimedia sound codec. As shown, the gain is set at 100 (40 dB), although it can be set to other gains depending on the microphone output levels. Figure 32 shows the preamplifier’s harmonic distortion performance with 1 V rms output while operating from a single +5 V supply. The SSM2135 is biased to 2.25 V by the VREF pin of the AD1848 codec. The same voltage is buffered by the 2N4124 transistor to provide “phantom power” to the microphone. A typical electret condenser microphone with an impedance range of 100 Ω to 1 kΩ works well with the circuit. This power booster circuit may be omitted for dynamic microphone elements. 10kΩ 1/2 SSM2135 10µF L CH 32 0.1µF 10µF 5 8 R CH 0.1µF 7 AGND +5V L CHANNEL MIC IN 100Ω 10µF 3 2kΩ +5V 2N4124 10kΩ 2 8 AD1848 10µF 1 29 +5V 0.1µF 35/36 34/37 32 6 1/2 470µF 4 SSM2135 8.66kΩ ROUT 41 10kΩ 1/2 4 SSM2135 LMIC VCC GND VREF Figure 29. A Stereo Headphone Driver for Multimedia Sound Codec R CHANNEL MIC IN 10µF 2kΩ 10kΩ 5 7 10µF 100Ω 6 0.1µF AD1848 28 RMIC Figure 30 shows the total harmonic distortion characteristics versus frequency driving into a 32 Ω load, which is a very typical impedance for a high quality stereo headphone. The SSM2135 has excellent power supply rejection, and as a result, is tolerant of poorly regulated supplies. However, for best sonic quality, the power supply should be well regulated and heavily bypassed to minimize supply modulation under heavy loads. A minimum of 10 µF bypass is recommended. 1/2 SSM2135 10kΩ Figure 31. Low Noise Microphone Preamp for Multimedia Sound Codec Figure 30. Headphone Driver THD+N vs. Frequency into a 32 Ω Load (VS = +5 V, with 80 kHz Low-Pass Filter) Figure 32. MIC Preamp THD+N Performance (VS = +5 V, AV = 40 dB, VOUT = 1 V rms, with 80 kHz Low-Pass Filter) –8– REV. D SSM2135 An 18-Bit Stereo CD-DAC Output Amplifier A Single Supply Differential Line Receiver The SSM2135 makes an ideal single supply stereo output amplifier for audio D/A converters because of its low noise and distortion. Figure 33 shows the implementation of an 18-bit stereo DAC channel. The output amplifier also provides low-pass filtering for smoothing the oversampled audio signal. The filter’s cutoff frequency is set at 22.5 kHz and it has a maximally flat response from dc to 20 kHz. As mentioned above, the amplifier’s outputs can drive directly into a stereo headphone that has impedance as low as 25 Ω with no additional buffering required. +5V SUPPLY Receiving a differential signal with minimum distortion is achieved using the circuit in Figure 35. Unlike a difference amplifier (a subtractor), the circuit has a true balanced input impedance regardless of input drive levels. That is, each input always presents a 20 kΩ impedance to the source. For best common-mode rejection performance, all resistors around the differential amplifier must be very well matched. Best results can be achieved using a 10 kΩ precision resistor network. 10kΩ +5V 10µF+0.1µF 1 2 3 4 5 6 7 8 VL LL DL CK DR LR 18-BIT DAC VBL 1/2 SSM2135 16 15 3 7.68kΩ 9.76kΩ 2 330pF 7.68kΩ 100pF 8 1 4 47kΩ 220µF LEFT CHANNEL OUTPUT 20kΩ 2 3 8 1 18-BIT SERIAL REG. VREF VOL 14 13 DIFFERENTIAL AUDIO IN 20kΩ 1/2 4 SSM2135 10kΩ 20kΩ 10Ω 10µF AUDIO OUT 6 7 5 2.0V AD1868 18-BIT SERIAL REG. VREF AGND 12 11 1/2 SSM2135 1 +5V 8 4 3 2 VOR DGND VBR 18-BIT DAC VS 7.68kΩ 7.68kΩ 9.76kΩ 6 330pF 5 7 47kΩ 1/2 SSM2135 100pF 220µF 10 9 RIGHT CHANNEL OUTPUT 1µF 100Ω 0.1µF 2.5kΩ 7.5kΩ +5V 5kΩ 1/2 SSM2135 Figure 33. +5 V Stereo 18-Bit DAC A Single Supply Differential Line Driver Signal distribution and routing is often required in audio systems, particularly portable digital audio equipment for professional applications. Figure 34 shows a single supply line driver circuit that has differential output. The bottom amplifier provides a 2 V dc bias for the differential amplifier in order to maximize the output swing range. The amplifier can output a maximum of 0.8 V rms signal with a +5 V supply. It is capable of driving into 600 Ω line termination at a reduced output amplitude. 1kΩ +5V 10µF+0.1µF 2 100µF AUDIO IN 1kΩ 6 10kΩ 2.0V 7 5 3 4 8 1 Figure 35. Single Supply Balanced Differential Line Receiver A Pseudo-Reference Voltage Generator For single supply circuits, a reference voltage source is often required for biasing purposes or signal offsetting purposes. The circuit in Figure 36 provides a supply splitter function with low output impedance. The 1 µF output capacitor serves as a charge reservoir to handle a sudden surge in demand by the load as well as providing a low ac impedance to it. The 0.1 µF feedback capacitor compensates the amplifier in the presence of a heavy capacitive load, maintaining stability. The output can source or sink up to 12 mA of current with +5 V supply, limited only by the 100 Ω output resistor. Reducing the resistance will increase the output current capability. Alternatively, increasing the supply voltage to 12 V also improves the output drive to more than 25 mA. VS+ = +5V → +12V R3 2.5kΩ C1 0.1µF R1 5kΩ 2 1/2 SSM2135 1kΩ DIFFERENTIAL AUDIO OUT 1/2 SSM2135 2.5kΩ 0.1µF 100Ω 1 3 4 5kΩ R2 5kΩ +5V 8 2 +5V 7.5kΩ 8 1/2 SSM2135 3 4 R4 100Ω 1 + VS C2 1µF 2 OUTPUT 1µF 1/2 SSM2135 Figure 34. Single Supply Differential Line Driver Figure 36. Pseudo-Reference Generator REV. D –9– SSM2135 A Digital Volume Control Circuit A Logarithmic Volume Control Circuit Working in conjunction with the AD7528/PM7528 dual 8-bit D/A converter, the SSM2135 makes for an efficient audio attenuator, as shown in Figure 37. The circuit works off a single +5 V supply. The DAC’s are biased to a 2 V reference level which is sufficient to keep the DAC’s internal R-2R ladder switches operating properly. This voltage is also the optimal midpoint of the SSM2135’s common-mode and output swing range. With the circuit as shown, the maximum input and output swing is 1.25 V rms. Total harmonic distortion measures a respectable 0.01% at 1 kHz and 0.1% at 20 kHz. The frequency response at any attenuation level is flat to 20 kHz. Each DAC can be controlled independently via the 8-bit parallel data bus. The attenuation level is linearly controlled by the binary weighting of the digital data input. Total attenuation ranges from 0 dB to 48 dB. 3 Figure 38 shows a logarithmic version of the volume control function. Similar biasing is used. With an 8-bit bus, the AD7111 provides an 88.5 dB attenuation range. Each bit resolves a 0.375 dB attenuation. Refer to AD7111 data sheet for attenuation levels for each input code. +5V 0.1µF 3 47µF L AUDIO IN 10 15 DGND VIN 14 VDD 16 1 FB OUTA AGND 2 +5V 10µF+0.1µF 2 3 8 1 47µF L AUDIO OUT AD7111 +5V 0.1µF 1/2 4 SSM2135 R AUDIO IN 3 14 16 47µF 1 15 DGND VDD FB OUTA VIN AD7111 AGND 2 10 10 6 5 1/2 SSM2135 7 2kΩ 47µF R AUDIO OUT AD/PM-7528 L AUDIO IN 4 47µF FB OUTA 2 2 3 +5V 10µF+0.1µF 8 1 47µF L AUDIO OUT DATA IN & CONTROL 2.0V 1µF 0.1µF 100Ω 1 +5V +5V 8 4 2 3 7.5kΩ REF A DAC A 1/2 4 SSM2135 1/2 SSM2135 5kΩ DATA IN 6 CONTROL SIGNAL R AUDIO IN 15 16 18 47µF DACA/ DACB CS WR REF B FB OUTB 20 1 6 5 2kΩ 5 2.0V 1µF 0.1µF 100Ω 1 +5V 8 4 2 3 2.0V 7.5kΩ 19 Figure 38. Single Supply Logarithmic Volume Control 1/2 SSM2135 7 47µF R AUDIO OUT DAC B VDD 17 DGND 0.1µF +5V +5V 1/2 SSM2135 5kΩ Figure 37. Digital Volume Control –10– REV. D SSM2135 SPICE MACROMODEL *SSM2135 SPICE Macro-Model 9/92, Rev. A * JCB/ADI *Copyright 1993 by Analog Devices, Inc. * *Node Assignments * * Noninverting Input * Inverting Input * Positive Supply * Negative Supply * Output .SUBCKT SSM2135 3 2 7 4 6 * * INPUT STAGE R3 4 19 1.5E3 R4 4 20 1.5E3 C1 19 20 5.311E–12 I1 7 18 106E–6 IOS 2 3 25E–09 EOS 12 5 POLY(1) 51 4 25E–06 1 Q1 19 3 18 PNP1 Q2 20 12 18 PNP1 CIN 3 2 3E–12 D1 3 1 DY D2 2 1 DY EN 5 2 22 0 1 GN1 0 2 25 0 1E–5 GN2 0 3 28 0 1E–5 * * VOLTAGE NOISE SOURCE WITH FLICKER NOISE DN1 21 22 DEN DN2 22 23 DEN VN1 21 0 DC 2 VN2 0 23 DC 2 * * CURRENT NOISE SOURCE WITH FLICKER NOISE DN3 24 25 DIN DN4 25 26 DIN VN3 24 0 DC 2 VN4 0 26 DC 2 * * SECOND CURRENT NOISE SOURCE DN5 27 28 DIN DN6 28 29 DIN VN5 27 0 DC 2 VN6 0 29 DC 2 * * GAIN STAGE & DOMINANT POLE AT .2000E+01 HZ G2 34 36 19 20 2.65E–04 R7 34 36 39E+06 V3 35 4 DC 6 D4 36 35 DX VB2 34 4 1.6 * * SUPPLY/2 GENERATOR ISY 7 4 0.2E–3 R10 7 60 40E+3 R11 60 4 40E+3 C3 60 0 1E–9 * * CMRR STAGE & POLE AT 6 kHZ ECM 50 4 POLY(2) 3 60 2 60 0 1.6 1.6 CCM 50 51 26.5E–12 RCM1 50 51 1E6 RCM2 51 4 1 * * OUTPUT STAGE R12 37 36 1E3 R13 38 36 500 C4 37 6 20E–12 C5 38 39 20E–12 M1 39 36 4 4 MN L=9E–6 W=1000E–6 AD=15E–9 AS=15E–9 M2 45 36 4 4 MN L=9E–6 W=1000E–6 AD=15E–9 AS=15E–9 5 39 47 DX D6 47 45 DX Q3 39 40 41 QPA 8 VB 7 40 DC 0.861 R14 7 41 375 Q4 41 7 43 QNA 1 R17 7 43 15 Q5 43 39 6 QNA 20 Q6 46 45 6 QPA 20 R18 46 4 15 Q7 36 46 4 QNA 1 M3 6 36 4 4 MN L=9E–6 W=2000E–6 AD=30E–9 AS=30E–9 * * NONLINEAR MODELS USED * .MODEL DX D (IS=1E–15) .MODEL DY D (IS=1E–15 BV=7) .MODEL PNP1 PNP (BF=220) .MODEL DEN D(IS=1E–12 RS=1016 KF=3.278E–15 AF=1) .MODEL DIN D(IS=1E–12 RS=100019 KF=4.173E–15 AF=1) .MODEL QNA NPN(IS=1.19E–16 BF=253 VAF=193 VAR=15 RB=2.0E3 + IRB=7.73E–6 RBM=132.8 RE=4 RC=209 CJE=2.1E–13 VJE=0.573 + MJE =0.364 CJC=1.64E–13 VJC=0.534 MJC=0.5 CJS=1.37E–12 + VJS=0.59 MJS=0.5 TF=0.43E–9 PTF=30) .MODEL QPA PNP(IS=5.21E–17 BF=131 VAF=62 VAR=15 RB=1.52E3 + IRB=1.67E 5–RBM=368.5 RE=6.31 RC=354.4 CJE=1.1E–13 + VJE=0.745 MJE=0.33 CJC=2.37E–13 VJC=0.762 MJC=0.4 + CJS=7.11E–13 VJS=0.45 MJS=0.412 TF=1.0E–9 PTF=30) .MODEL MN NMOS(LEVEL=3 VTO=1.3 RS=0.3 RD=0.3 TOX=8.5E–8 + LD=1.48E–6WD=1E–6 NSUB=1.53E16UO=650 DELTA= 10VMAX=2E5 + XJ=1.75E–6 KAPPA=0.8 ETA=0.066 THETA=0.01TPG=1 CJ=2.9E–4 + PB=0.837 MJ=0.407 CJSW=0.5E–9 MJSW=0.33) * .ENDS SSM-2135 REV. D –11– SSM2135 OUTLINE DIMENSIONS Dimensions shown in inches and (mm). 8-Lead Plastic DIP (N-8) 8 5 0.280 (7.11) 0.240 (6.10) 1 4 0.070 (1.77) 0.045 (1.15) 0.430 (10.92) 0.348 (8.84) 0.210 (5.33) MAX 0.160 (4.06) 0.115 (2.93) 0.325 (8.25) 0.300 (7.62) 0.195 (4.95) 0.115 (2.93) 0.015 (0.381) 0.008 (0.204) 0.015 (0.381) TYP 0.130 (3.30) MIN 0.100 (2.54) BSC SEATING PLANE 0°- 15° 0.022 (0.558) 0.014 (0.356) 8-Lead Narrow-Body (SO-8) 8 5 0.2440 (6.20) 0.2284 (5.80) 1 4 0.1574 (4.00) 0.1497 (3.80) 0.1968 (5.00) 0.1890 (4.80) 0.0098 (0.25) 0.0040 (0.10) 0.0688 (1.75) 0.0532 (1.35) 0.0196 (0.50) × 45° 0.0099 (0.25) 0°- 8° 0.0500 (1.27) BSC 0.0192 (0.49) SEATING 0.0138 (0.35) PLANE 0.0098 (0.25) 0.0075 (0.19) 0.0500 (1.27) 0.0160 (0.41) –12– REV. D PRINTED IN U.S.A. C1772a–10–10/97