Products

JoAnn Close is a design group leader at Analog Devices, Inc. Among the products that she has designed are the:

• ADA4941-1 Single-supply, low power differential 18-bit ADC driver.
• ADA4841-1 Low power, low noise, low distortion rail-to-rail output amplifier (ADA4841-2 is the dual version).
• AD8045 JoAnn's first 1GHz chip is an ultralow distortion voltage feedback amplifier.
• AD8139 Ultra low noise, fully differential ADC driver. See the analogZone review that calls it a "gem" with superb dynamic performance criteria.
• AD8065 One of the FastFETs^® - a fast low-noise FET input operational amplifier (AD8066 is the dual version; AD8067 is a decompensated version, stable at gains of 10 and greater).
• AD8391 xDSL line drive amplifier, suitable for voice over DSL applications
• AD8018 Low-power ADSL line driver suitable for USB and PCMCIA
• AD8061 Really fast single supply operational amplifier (AD8062 is the dual version; AD8063 is a single with disable)
• AD8170 Very high speed 2:1 buffered multiplexer (AD8174 is 4:1 version). Also see Eamon Nash's article on Buffered Multiplexers for Video Applications.
• AD822 Dual precision, low power FET input operational amplifier with single supply capability (AD820 is the single version, AD824 is the quad version)
• AD795 Low noise, precision FET input operational amplifier
• AD549 Monolithic electrometer operational amplifier with very low input bias current
• AD648 Matched pair of low power, precision monolithic operational amplifiers (AD548 is the single version)

Patents

• Bipolar rail-to-rail input stage with selectable transition threshold
• High output current operational amplifier output stage
• Very low input current JFET amplifier

Blog

• Blonde and Bipolar

Publications

• Close, J. P. and Santos, F. A JFET input single supply operational amplifier with rail-to-rail output. Proceedings of the Bipolar/BiCMOS Circuits and Technology Meeting, October 4-5, 1993, pp. 149-152.
• Close, J. P., DeVito, L. M. and Quinn, D. E. Hall cell geartooth sensor with 15 Gauss sensitivity. International Solid-State Circuits Conference Digest of Technical Papers, Vol. 33, February 14-16, 1990, pp. 240-241, 304. 
• Close, J. P. and Counts, L. W. A 50-fA junction-isolated operational amplifier. IEEE Journal of Solid-State Circuits, 23 (3), June 1988, 843-851.
• Close, J. P. and Counts, L. W. A 50fa input current junction-isolated JFET opamp. International Solid-State Circuits Conference Digest of Technical Papers, Vol. 29, February 19-21, 1986, pp. 12-13, 284-285.

Copyright © 2009 by Michael Good and JoAnn Close.

Last updated November 2, 2009.