ADA4950-1

The ADA4950-x is available in a Pb-free, 3 mm * 3 mm, 16-lead LFCSP (ADA4950-1, single)or a Pb-free, 4 mm * 4 mm, 24-lead LFCSP (ADA4950-2, dual). The pinout has been optimized to facilitate PCB layout and minimize distortion. The ADA4950-1/ ADA4950-2 are specified to operate over the -40°C to +105°C temperature range; both operate on supplies from +3 V to ±5 V. The ADA4950-1/ADA4950-2 are fabricated using the Analog Devices, Inc., proprietary silicon-germanium (SiGe)complementary bipolar process, enabling them to achieve low levels of distortion and noise at low power consumption. The low offset and excellent dynamic performance of the ADA4950-x make it well suited for a wide variety of data acquisition and signal processing applications. The ADA4950-1/ADA4950-2 are gain-selectable versions of the ADA4932-1/ADA4932-2 with on-chip feedback and gain resistors. They are ideal choices for driving high performance ADCs as single- ended-to-differential or differential-to-differential amplifiers. The output common-mode voltage is user adjustable by means of an internal common-mode feedback loop, allowing the ADA4950-1/ ADA4950-2 output to match the input of the ADC. The internal feedback loop also provides exceptional output balance as well as suppression of even-order harmonic distortion products. Differential gain configurations of 1, 2, and 3 are easily realized with internal feedback networks that are connected externally to set the closed-loop gain of the amplifier.

The features of ADA4950-1 can be summarized as (1)high performance at low power; (2)high speed -3 dB bandwidth of 750 MHz, G = 1/ 0.1 dB flatness to 210 MHz, VOUT, dm = 2 V p-p, RL, dm = 200 / Slew rate: 2900 V/s, 25% to 75%/ Fast 0.1% settling time of 9 ns; (3)low power: 9.5 mA per amplifier; (4)low harmonic distortion 108 dB SFDR @ 10 MHz/ 98 dB SFDR @ 20 MHz; (5)low output voltage noise: 9.2 nV/Hz, G = 1, RTO; (6)±0.2 mV typical input offset voltage; (7)selectable differential gains of 1, 2, and 3; (8)differential-to-differential or single-ended-to-differential operation; (9)adjustable output common-mode voltage; (10)input common-mode range shifted down by 1 VBE; (11)wide supply range: +3 V to ±5 V; (12)available in 16-lead and 24-lead LFCSP packages.

The absolute maximum ratings of ADA4950-1 are (1)supply voltage 11 V; (2)power dissipation: See Figure 4; (3)Input Current, +INx, -INx, PD: ±5 mA; (4)storage temperature range: -65°C to +125°C; (5)operating temperature range ADA4950-1: -40°C to +105°C/ADA4950-2: -40°C to +105°C; (6)lead temperature (Soldering, 10 sec): 300°C; (7)junction temperature: 150°C.