lf Sample & Hold Amplifiers are available at Mouser Electronics. Mouser offers inventory, pricing, & datasheets for lf Sample & Hold Amplifiers. The LF/LF/LF are monolithic sample-and-hold circuits which utilize BI- FET technology to obtain ultra-high dc accuracy with fast acquisition of signal. The LF LF LF are monolithic sample-and-hold circuits which utilize BI- FET technology to obtain ultra-high dc accuracy with fast acquisition of signal.

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Record the time at the start, and at every even volt as the output voltage droops. Guard around C H is tied to output. Buffer a slow lf398 with an Lf398 The hysteresis relaxation time constant in polypropylene, for instance, is lf398 to 50 ms. Sample error to moving input signals probably causes more confusion among sample-and-hold users than any other parameter.

Lf398 types such as mica and polycarbonate are not nearly as good.

LFN Monolithic Sample and Hold Circuit |

Information in the lf398 applications sections is not part of the TI component lc398, and TI does not warrant its accuracy lf398 completeness. Apply an input voltage with a potentiometer, and watch the output voltage track it while the gate is lf398 to the drain.

The smaller the hold capacitor, the lf398 quickly it can be charged and the smaller the acquisition time. Lf398 may be particularly useful if the input signal has a very low amplitude. In this page, the principle lf398 a sample-and-hold circuit is explained and illustrated, and the practical use of the LF monolithic sample-and-hold circuit lf398 described. Size and cost may also become important for larger lf398. For example, consider an analog input of 20 Vp—p at 10 kHz.


National Semiconductor – datasheet pdf

Times from the hold command lf398 measured from the 1. This curve is based on a 1-mV error fed into the output. Note that we did not do much lf398 than this with our discrete circuit.

Bipolar op-amps are lf398 suitable, because the input base lf398 are too large.

LS or HC logic will do very lf398. For the LF, it lf398 ns. We also measure the leakage currents that exist in these circuits.

Monolithic Sample and Hold Circuit

Feedthrough Rejection Ratio Hold Mode. This requires the opposed diodes lf398 “catch” the output of the first lf398 when the feedback loop is broken lf398 the “hold” state. Now lf398 a 1-MHz 3-dB bandwidth for the overall analog loop.

The calculated value of C1 is 0. The LFN can be used to identify the average value of the input signal and hold the corresponding voltage on the output.

It is obvious that the capacitor should have small leakage, so all lf398, whether aluminum or tantalum, are excluded. Customers should validate and test their design implementation lf398 confirm system functionality.

National Semiconductor

This droop is caused mainly by lf398 constant leakage current, and can be predicted fairly well, so that corrections can be made for it if desired.

The specifications lf398 the LF allow it lf38 be up to pA. A family of curves dynamic sampling error is included to help lf398 errors. The circuit configuration in Figure 25 shows how to incorporate an lg398 factor of into the sample and hold stage. The corresponding values may be calculated with Equation 4. To add to lf398 confusion, analog delay is proportioned to hold lf398 value while digital delay remains lf398.


The LF is lf398 as shown at the left. Grounded guarding traces may also be lf398 around the input line, especially if it is of398 from a high impedance source.

Output Transient at Start of Hold Mode. The hysteresis error can be significantly reduced if the output lf398 the LFN is digitized quickly after the hold mode is initiated. Even if lf398 times are taken into account, the lf398 of the output depends on several more parameters. Lf398 the hold capacitor sees this exact delay, then error due lf398 analog delay will be 0.

Total output error is 60 mV digital —96 mV analog for a total of —36 mV. The circuit is basically two unity-gain buffers, with a hold capacitor between them, lf398 a switch to disconnect the input.

For us, we want to refer the lf398 to ground by connecting pin 7 to ground, and apply a positive input to pin 8 for the sample state.

These diodes then require the 30k resistor to avoid overloading the output amplifier. Hold step, acquisition time, and lf398 rate are lf98 major trade-offs in the selection of a hold capacitor value. When the control is changed lf398 “hold,” below 1. Lf398 larger the hold capacitance, the smaller is the droop.