DA1855A High-performance 100 MHz Differential Amplifier The DA1855A is a stand-alone, high-performance differential amplifier providing the Key Features fastest overdrive recovery of any commercially available product. This unique capability allows the amplifier to make measurements that would normally be limited by oscilloscope Full control from oscilloscope through overdrive recovery. ProBus interface The DA1855A is a stand-alone, DA1855A, including probe attenuation, DC to 100 MHz bandwidth high-performance 100 MHz differential amplifier gain and attenuator settings, amplifier. It is intended to act as a is automatically displayed. Outstanding 100,000: 1 Common signal conditioning preamplifier for Mode Rejection Ratio (CMRR) The DA1855A has a bandwidth of oscilloscopes, digitizers and spectrum 100 MHz, but any one of the three Gain of X1 or X10 analyzers, providing differential 3-pole bandwidth limit filters can be measurement capability to instru- Industry-leading overdrive recovery selected to reduce bandwidth to ments having only a single-ended 20 MHz, 1 MHz or 100 kHz to limit Low noise input. When used with a DA1855A, noise above the frequency of interest. Selectable BW limiting oscilloscopes can obtain Common The DA1855A output is carefully Mode Rejection Ratio (CMRR) and T wo gain control modes when limited to 500 mV, so that the overdrive recovery performance levels connected to a Teledyne LeCroy oscilloscope is not overdriven by large previously unobtainable. oscilloscope inputs. This allows many oscilloscopes Amplifier gain can be set to 1 or 10. to directly measure the settling of Built-in Pr ecision Voltage A built-in input attenuator can D/A converters with 14-bit (60 ppm) Generator (PVG) be separately set to attenuate precision, better than any other Comparator and true signals by a factor of 10, providing differential comparator. differential offset modes gains of 10, 1, or 0.1 and common The DA1855A features a built-in mode dynamic range of 15.5 V (1) Precision Voltage Generator (PVG) or 155 V (10). Optional probes that can be set to any voltage between increase the maximum input signal 15.5 V (10 V in Differential Offset. and common mode ranges in The PVGs output can be selected as propor tion to their attenuation ratio but an input to the inverting (-) input of the do not exceed their maximum input amplifier for operation as a differential voltage rating. Effective gain of the SPECIFICATIONS AND ORDERING INFORMATION comparator or applied internally as a true differential offset that are much often more accurate than the oscilloscope is voltage. The PVG is also available for external use through capable of by itself. The output of the PVG is available for a rear panel connector. external use via a rear panel connector. The DA1855A operates from 90 to 250 VAC line without True Differential Offset Mode line switching. High-performance differential probes The DA1855A has built-in Precision Voltage Generator such as the DXC100 10/100 high CMRR probes are can be used to generate a true differential offset while still recommended. allowing both inputs to be used as differential inputs. The offset range can be as high as 50,000 divisions and the Overdrive Recovery generator has 5 1/2 digit resolution. This mode facilitates With a 100 probe, the DA1855A settles to within making measurements such as changes to a transistors 100mV referred to input, from a 400 V input signal base to emitter voltage caused by variations in temperature within 100ns. With attenuating probes, this allows and/or current. Used in this mode, the voltage generator the in circuit measurement of dynamic saturation in switch can be set to a value that will zero out the static value mode power converter switching devices. of the junctions on voltage. The DA1855As differential Comparator Mode measurement capability will reject any dynamic signal The DA1855A becomes a differential comparator when common to both sides of the junction, and the oscilloscope the internal PVG output is selected as the amplifiers is left to measure only the changes in the junction voltage. inverting (-) input. In this mode, the DA1855A can be used Autobalance to measure relatively small signals that are riding on large Each time either gain setting button is pressed, the AC or DCcomponents (within the precision and accuracy DA1855A automatically adjusts the amplifiers DC balance. limitations of the PVG). Therefore, an oscilloscope, when used with the DA1855A, can make voltage measurements Specifications Ordering Information (contd) Main Specifications Product Description Product Code Bandwidth > 100 MHz 10 1 M Passive Attenuator for DXC Series Probes DA101* 2 Ch,100 MHz Differential Amplifier DA1855A-PR2 Electrical Characteristics with Precision Voltage Source Rise time (typical) < 3.5 ns DA1855A with Rackmount DA1855A-RM DA1855A with Rackmount DA1855A-PR2-RM Ordering Information (must be ordered at time of purchase, no retrofit) Product Description Product Code *Must be used with DA Series Differential Amplifiers Differential Amplifiers Customer Service 1 Ch, 100 MHz Differential Amplifier DA1855A Teledyne LeCroy oscilloscopes and probes are designed, built, and tested with Precision Voltage Source to ensure high reliability. In the unlikely event you experience difficulties, 100 or 10 Selectable, 250 MHz DXC100A* our digital oscilloscopes are fully warranted for three years and our probes Passive Differential Probe Pair are warranted for one year. 1, 50 MHz Passive Differential Probe Pair DXC200* This warranty includes: 100, 250 MHz 2.5kv, High Voltage Probe Pair DXC-5100* No charge for return shipping Long-term 7-year support (requires DA101 for full performance) Upgrade to latest software at no charge 1-800-5-LeCroy Local sales offices are located throughout the world. teledynelecroy.com Visit our website to find the most convenient location. 2018 by Teledyne LeCroy, Inc. All rights reserved. Specifications, prices, availability, and delivery subject to change da1855a-ds-07feb18 without notice. Product or brand names are trademarks or requested trademarks of their respective holders.