Low-Noise, Differential Audio Preamplifier IC THAT1570 FEATURES APPLICATIONS y Low Noise: y Microphone Preamplifiers 1 nV/Hz input noise (60 dB gain) y Digitally-Controlled Microphone y Low THD+N: Preamplifiers 0.0003% 30 dB gain 0.0008% 40 dB gain y Differential Low-Noise Preamplifiers y Low Current: 7.5 mA typ y Differential Summing Amplifiers y Wide Bandwidth: 4.2MHz 40dB gain y Differential Variable-Gain Amplifiers y High Slew Rate: 53 V/s y Wide Signal Swing: >28.7dBu y Moving-Coil Transducer Amplifiers (18V supplies) y Line Input Stages y Gain adjustable from 0 to >60 dB y Differential output y Audio y Small 4 x 4mm QFN16 package y Sonar y Mates with THAT5171 y Instrumentation Digital Preamplifier Controller IC Description The THAT1570 is a versatile, high performance The 1570 s differential output simplifies connec- current-feedback amplifier suitable for differential tion to differential input devices such as A/D convert- microphone preamp and bus summing applications. ers. The part operates from as little as 5V up The IC comes in a small QFN package, which saves through 18V supplies. Running on 18V supplies, PCB space over discrete and other integrated at unity gain, the part accepts >+28dBu input signals. solutions. The 1570 is designed to mate perfectly with Gain is adjusted via three external resistors (R , A THATs 5171 Digital Preamplifier Controller IC. The R , and R ), making it possible to optimize noise over B G part-pair comprises an optimized, digitally controlled a wide range of gains. The 1570 supports the tradi- audio preamplifier. tional approach to gain control (viz., THAT s 1510 or Designed from the ground up in THAT s comple- 1512) by fixing R and R , and varying R to control A B G mentary bipolar dielectric-isolation process and gain. However, the 1570 also supports varying all including laser-trimmed Si-Chrome thin-film resistors, three resistors simultaneously with a dual-gang poten- the 1570 improves on existing integrated microphone tiometer or a switched resistor network. This flexible preamps by offering more versatile gain configuration, approach enables the designer to optimize noise over a lower noise at low gains, higher slew rate, and lower wider range of gains than is possible with fixed R and A distortion. R . B Pin Name QFN Pin N/C* 1 OUT2 2 OUT1 3 N/C* 4 N/C* 5 Rg1 6 IN1 7 N/C* 8 N/C* 9 IN2 10 N/C* 11 V- 12 V+ 13 N/C* 14 Rg2 15 N/C* 16 V- Thermal Pad Table 1. Pin Assignments Figure 1. THAT1570 Block Diagram * N/C pins should be left open and not connect to other traces on the PCB. THAT Corporation 45 Sumner Street Milford, MA 01757-1656 USA Tel: +1 508 478 9200 Fax: +1 508 478 0990 Web: www.thatcorp.com Copyright 2015, THAT Corporation. Document 600132 Rev 03Document 600132 Rev 03 Page 2 of 12 THAT1570 Low-Noise Differential Audio Preamplifier IC 1 SPECIFICATIONS 2,3 Absolute Maximum Ratings Supply Voltage (V+) - (V-) 40 V Operating Temperature Range (T ) -40 to +85 C OP Maximum Input Voltage (V ) V+ to V- Output Short-Circuit Duration (t ) Continuous IMax SH Storage Temperature Range (T ) -40 to +125 C Junction Temperature (T ) +125 C STG JMAX 2,4,5 Electrical Characteristics Parameter Symbol Conditions Min Typ Max Units Power Supply Supply Voltage V+ -(V-) Referenced to GND 5 18 V Supply Current I+ -(I-) No Signal 7.5 10 mA Input Characteristics Input Bias Current IB No signal either input connected to GND 6.4 22 A Input Offset Current I No signal -2.2 +2.2 A B-OFF Differential Input Offset Voltage V No signal, Inputs connected to GND OS 0 dB gain -5.25 +5.25 mV +60 dB gain -255 +255 V Input Common Mode Voltage Range V Common Mode (V-) + 4 (V+) - 4 V IN CM Input Impedance Z Differential IN DIFF 20 dB gain 58 1 M pF 40 dB gain 58 3.5 M pF 60 dB gain 57 28.7 M pF Z Common Mode IN CM All gains 29.4 1.4 M pF Maximum Differential Input Level V R = 26.8 dBu IN-BAL G Output Characteristics Total Differential Output Offset G = gain -(5+0.25*G) (5+0.25*G) mV Common Mode Output Voltage V No signal IN1, IN2 connected to GND -610 mV OSCM Maximum Single Output Voltage V R = 2 k (V-) + 2.4 (V+) - 1.4 V OUT-SINGLE L Differential Short Circuit Current I R = 0 Cold start 42 mA SC L R = 0 Continuous 28 mA L Maximum Capacitive Load C Over entire temperature range 100 pF L MAX Stable operation 50% overshoot 400 pF Maximum Differential Output Level VOUT RL= 2 k 26.6 dBu 1. All specifications are subject to change without notice. 2. Unless otherwise noted, TA = 25C, V+ = +15V, V- = -15V. 3. Stresses above those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings only the functional operation of the device at these or any other conditions above those indicated in the operational sections of this specification is not impli ed. Exposure to absolute maximum rating condi- tions for extended periods may affect device reliability. 4. 0 dBu = 0.775 Vrms 5. Unless otherwise noted, R = R = 2.21 k C = 10 pF A B L THAT Corporation 45 Sumner Street Milford, MA 01757-1656 USA Tel: +1 508 478 9200 Fax: +1 508 478 0990 Web: www.thatcorp.com Copyright 2015, THAT Corporation All rights reserved.