a Balanced Line Driver SSM2142 FUNCTIONAL BLOCK DIAGRAM FEATURES Transformer-Like Balanced Output Drives 10 V RMS Into a 600 V Load V IN Stable When Driving Large Capacitive Loads and Long Cables 50W Low Distortion +OUT FORCE 0.006% typ 20 Hz20 kHz, 10 V RMS into 600 V High Slew Rate +OUT SENSE 15 V/ms typ 10kW Low Gain Error OUT SENSE (Differential or Single-Ended) 0.7% typ Outputs Short-Circuit Protected Available In Space-Saving 8-Pin Mini-DIP Package 50W Low Cost OUT FORCE APPLICATIONS Audio Mix Consoles ALL RESISTORS 30kW Distribution Amplifiers UNLESS OTHERWISE 10kW INDICATED Graphic and Parametric Equalizers Dynamic Range Processors GND Digital Effects Processors Telecommunications Systems Industrial Instrumentation Hi-Fi Equipment GENERAL DESCRIPTION Based on a cross-coupled, electronically balanced topology, the The SSM2142 is an integrated differential-output buffer SSM2142 mimics the performance of fully balanced amplifier that converts a single-ended input signal to a balanced transformer-based solutions for line driving. However, the output signal pair with high output drive. By utilizing low noise SSM2142 maintains lower distortion and occupies much less thermally matched thin film resistors and high slew rate board space than transformers while achieving comparable amplifiers, the SSM2142 helps maintain the sonic quality of common-mode rejection performance with reduced parts count. audio systems by eliminating power line hum, RF interference, The SSM2142 in tandem with the SSM2141 differential voltage drops, and other externally generated noise commonly receiver establishes a complete, reliable solution for driving and encountered with long audio cable runs. Excellent rejection of receiving audio signals over long cables. The SSM2141 features common-mode noise and offset errors is achieved by laser an Input Common-Mode Rejection Ratio of 100 dB at 60 Hz. trimming of the onboard resistors, assuring high gain accuracy. Specifications demonstrating the performance of this typical The carefully designed output stage of the SSM2142 is capable system are included in the data sheet. of driving difficult loads, yielding low distortion performance despite extremely long cables or loads as low as 600 , and is stable over a wide range of operating conditions. REV. C 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.(V = 618 V, 408C T +858C, operating in differential mode unless otherwise S A SSM2142SPECIFICATIONS noted. Typical characteristics apply to operation at T = +258C.) A Parameter Symbol Conditions Min Typ Max Units INPUT IMPEDANCE Z 10 k IN INPUT CURRENT I V = 7.071 V 750 900 A IN IN GAIN, DIFFERENTIAL 5.8 5.98 dB GAIN, SINGLE-ENDED Single-Ended Mode 5.7 5.94 dB GAIN ERROR, DIFFERENTIAL R = 600 0.7 2 % L POWER SUPPLY REJECTION RATIO STATIC PSRR V = 13 V to 18 V 60 80 dB S OUTPUT COMMON-MODE REJECTION OCMR See Test Circuit f = 1 kHz 45 dB OUTPUT SIGNAL BALANCE RATIO SBR See Test Circuit f = 1 kHz 40 dB TOTAL HARMONIC DISTORTION Plus Noise THD+N 20 Hz to 20 kHz, 0.006 % V = 10 V rms, R = 600 O L SIGNAL-TO-NOISE RATIO SNR V = 0 V 93.4 dBu IN HEADROOM HR CLIP Level = 10.5 V rms +93.4 dBu SLEW RATE SR 15 V/s OUTPUT COMMON-MODE 1 VOLTAGE OFFSET V R = 600 250 25 250 mV OOS L DIFFERENTIAL OUTPUT VOLTAGE OFFSET V R = 600 50 15 50 mV OOD L DIFFERENTIAL OUTPUT VOLTAGE SWING V = 7.071 V 13.8 14.14 V IN OUTPUT IMPEDANCE Z 45 50 55 O SUPPLY CURRENT I Unloaded, V = 0 V 5.5 7.0 mA SY IN OUTPUT CURRENT, SHORT CIRCUIT I 60 70 mA SC NOTES 1 Output common-mode offset voltage can be removed by inserting dc blocking capacitors in the sense lines. See Applications Information. Specifications subject to change without notice. ABSOLUTE MAXIMUM RATINGS* PIN CONNECTIONS Supply Voltage 18 V Storage Temperature 60C to +150C 8-Pin Plastic DIP 16-Pin Wide Body SOL Lead Temperature (Soldering, 60 sec) +300C (P Suffix) (S Suffix) Junction Temperature +150C 16 Operating Temperature Range 40C to +85C NC 1 NC 15 Output Short Circuit Duration (Both Outputs) Indefinite NC 2 NC 3 14 + FORCE FORCE *Stresses above those listed under Absolute Maximum Ratings may cause 13 permanent damage to the device. These are stress ratings only the functional 4 + SENSE SENSE operation of the device at these or any other conditions above those indicated in the 5 12 +V GROUND operational sections of this specification is not implied. Exposure to absolute V 6 11 V IN maximum rating conditions for extended periods may affect device reliability. 7 10 NC NC 9 8 NC NC 2 REV. C