Sample and Hold Circuits
Last Updated on:
Tuesday, October 28, 2014 02:16 PM


Circuits Designed by Dave Johnson, P.E. :
  • AIR TRANSPARENCY MONITOR, XENON FLASH RECEIVER
    I designed this circuit many years ago to monitor the quality of a mile long column of air for future optical communications experiments. The transmitter system (circuit 72 below) uses a powerful xenon flash in conjunction with a large 12 inch Fresnel lens at the transmitter end and a matching 12-inch lens with a PIN photo diode at the receiver. The receiver system was connected to a weather station and a computer to collect the changes in intensity of the light flashes under different weather conditions. It has the potential for a 30+-mile range. I have also used this system to conduct cloud bounce experiments.


Links to electronic circuits, electronic schematics, designs for engineers, hobbyists, students & inventors:

Air Transparency Monitor, pg 1 -  I designed this circuit many years ago to monitor the quality of a mile long column of air for future optical communications experiments. The transmitter system (circuit 72 below) uses a powerful xenon flash in conjunction with a large 12 inch Fresnel lens at the transmitter end and a matching 12-inch lens with a PIN photo diode at the receiver. The receiver system was connected to a weather station and a computer to collect the changes in intensity of the light flashes under different weather conditions. It has the potential for a 30+-mile range. I have also used this system to conduct cloud bounce experiments.... [Designed by David A. Johnson]
Air Transparency Monitor, pg 2 -  This is Page 2 of the air transparency monitor receiver circuit.... [Designed by David A. Johnson]
AN-266: Circuit Applications of Sample-Hold Amplifiers -  National Semiconductor Application Note  (app note added 2/06)
AN-270: Applying IC Sample & Hold Amplifiers -  AN-270 Analog Devices Application Notes....[App Note]
AN-284: Implement Infinite Sample-and-Hold Circuits using Analog Input/Output Ports -  AN-284 Analog Devices Application Notes....[App Note]
AN-294: Special Sample & Hold Techniques -  National Semiconductor Application Note  (app note added 2/06)

Calibrate scope jitter using a transmission line loop -  20-Sep-01 Issue of EDN  Digital-clock-period jitter is the variation in the period of a clock cycle compared with a nominal (average of many cycles] clock period. To accurately measure period jitter using an oscilloscope, you must subtract the oscilloscope jitter from the measured jitter. However, oscilloscopes rarely have a jitter specification, so you must determine the oscilloscope jitter.... [Design Idea by David Cuthbert, Micron Technology, Boise, ID]
Circuit Applications of Sample-Hold Amplifiers -  National Semiconductor Application Note  (app note added 2/06)
Circuit improves on temperature measurement -  2-May-02 Issue of EDN  When current pulses with a stable IHIGH/ILOW ratio modulate a semiconductor junction, the ensuing voltage difference (for example, ΔVBE for a bipolar transistor] is a linear function of the absolute (Kelvin] temperature, T. You can use this truism to make accurate temperature measurements. Technical literature has thoroughly covered the relationship (references 1 to 4] and has numerou.... [Design Idea by Alexander Bell, Infosoft International Inc, Rego Park, NY]
Circuit lets you test sample-and-hold amplifiers -  4-Mar-10 Issue of EDN  Measure voltage drop with a digital voltmeter.... [Design Idea by Marián Štofka, Slovak University of Technology, Bratislava, Slovakia]
Diagnose setup & hold times in synchronous & asynchronous circuits -  10/18/07  Video Design Ideas-EDN  Metastability of digital circuits can become a problem if you don't properly account for setup and hold times in synchronous circuits, or at random in the case of asynchronous inputs. (electronic Design Idea added 9/08] EDN is migrating links. This link is not verified.  Search the "title" + EDN for new link.
Dual-input sample-and-hold amplifier uses no external resistors -  14-Dec-07 Issue of EDN  A sample-and-hold amplifier sums two inputs and holds that sum when triggered.... [Design Idea by Marián Štofka, Slovak University of Technology, Bratislava, Slovakia]
Frequency to Voltage Converter uses Sample & Hold to Improve Response & Ripple -  National Semiconductor Application Notes,28-Jun-1996 (app note added 6/06)
Frequency-to-Voltage Converter uses Sample-and-Hold to Improve Response & Ripple -  National Semiconductor Application Note  (app note added 2/06)
Gain-of-two instrumentation amplifier uses no external resistors -  8-Nov-07 Issue of EDN  If the required voltage gain of a sample-and-hold amplifier is an integer, this circuit achieves a gain of two without using any power-dissipating external resistors.... [Design Idea by Marián Štofka, Slovak University of Technology, Bratislava, Slovakia]
Infinite Hold Circuit Zeros Out Long Term Drift -  03/03/94 EDN-Design Ideas....The infinite-hold circuit in Fig 1 automatically zeros out long-term drift from an instrument or a sensor. In operation, a control system (not shown]periodically takes the instrument or sensor off line and applies a known stimulus. The known stimulus generates a baseline-output signal.... [Design Idea by William R Penrose and Li Pan, Transducer Research, Naperville, IL]
Inverting sample-and-hold amplifier requires no external resistors -  2-Aug-07 Issue of EDN  Eliminating external feedback resistors in an inverting sample-and-hold amplifier allows it to exploit the full bandwidth of its op amps.... [Design Idea by Marián Štofka, Slovak University of Technology, Bratislava, Slovakia]
LB-45: Linear Brief 45 Frequency-to-Voltage Converter uses Sample-and-Hold to Improve Response & Ripple -  National Semiconductor Application Note  (app note added 2/06)
Low Cost Sample/ Hold Includes Two ICs -  Maxim Application Notes / 19 / Apr-07)....[App Note]
NCO technique helps µC produce clean analog signals -  04/15/99 Issue of EDN  A recent Design Idea described a method for producing an analog voltage from one digital output of a µC ("Generate an analog signal with a µC," EDN,Oct 22, 1998, pg 108]. The method involves generating a PWM output with a controlled duty cycle and filtering the switching waveform with a simple single-pole RC filter. Although this method provides an accurate....Page includes several designs.  Scroll to find this one....(EDN  Design Ideas] [Design Idea by Steve Ploss, Veridian Corp, Wright Patterson AFB, OH]
Precision T/H Amplifier uses 3.3 Volt Supply -  06/22/95 EDN-Design Ideas....The track-and-hold (T/H] circuit in Fig 1  works well in applications using a low-voltage single supply, such as in battery-powered designs. Despite the low supply voltage, output-signal dynamic range remains high thanks to the rail-to-rail output swing of the amplifiers and switches. S/N ratio is also high because.... EDN is migrating links. This link is not verified.  Search the "title" + "EDN" for new link.
RF Transmitter uses AMI encoding -  11/24/99 EDN-Design Ideas....Although alternate-mark-inversion (AMI]encoding is well-suited for direct-conversion FM transmission, designers often overlook the technique. AMI, a three-phase, synchronous-encoding technique, uses bipolar pulses to represent logic ones and no signal to.... EDN is migrating links. This link is not verified.  Search the "title" EDN for new link.
S/H circuit minimizes aperture -  04/15/99 Issue of EDN  Conventional sample-and-hold (S/H] circuits use one hold capacitor that charges during the track phase and disconnects during the hold phase. The voltage that the capacitor holds usually drives an A/D converter that operates synchronously with the S/H control signal.  This approach can sometimes place excessive demands on the S/H circuit's bandwidth and settling capabilities. You can improve performance....Page includes several designs.  Scroll to find this one.... [Design Idea by John Guy, Maxim Integrated Products, Sunnyvale, CA]
Sampling peak detector has shutdown feature -  16-May-02 Issue of EDN  You face a serious problem in using a slow ADC with a fast peak detector. The circuit in Figure 1 allows a slow ADC to measure a fast, sampled signal peak. The 100-MHz peak detector for ultrasonic-pulse sampling uses a fast MAX4231 amplifier from Maxim (www.maxim-ic.com].  This amplifier has a shutdown feature that facilitates power savings without losing the sampled information.... [Design Idea by Shyam Tiwari, Sensors Technology Private Ltd, Gwalior, India]
Special Sample & Hold Techniques -  National Semiconductor Application Note  (app note added 2/06)
Video Design Idea: Diagnose setup and hold times in synchronous and asynchronous circuits-  18-Oct-07 Issue of EDN  Metastability of digital circuits can become a problem if you don't properly account for setup and hold times in synchronous circuits, or at random in the case of asynchronous inputs.... [Design Idea by Staff]

Sample & Hold Circuits