Delay Lines Work Dallas Semiconductor Delay Lines Work? earl

The Datasheet Archive - 100 Million Datasheets from 7500 Manufacturers.

Delay Lines Work Dallas Semiconductor Delay Lines Work? earl

Datasheet Thumbnail

Top Searches for this datasheet

Note
Delay Lines Work
Dallas Semiconductor Delay Lines Work?
early eighties, Dallas Semiconductor first company develop all-silicon delay line. This provided smaller, more cost-effective alternative modular delay lines used time.
Generation DS1000 Delay Line
first Dallas delay lines consisted RC-based ramp generator comparator circuit that transitioned delay line output when certain voltage level ramp generator reached. Calibration performed factory wafer level using laser blow series fuses until desired delay achieved. There provision temperature compensation. Today, current generation lines more sophisticated. Maxim/Dallas all-silicon delay lines contain novel circuit consisting voltage-controlled delay line (VCDL) used conjunction with compensation circuit reduce delay variations caused changes process, temperature, voltage. Building silicon delay line very difficult. logic gate propagation delay used delay line. difficult part building delay line that precisely specific delay period that remains consistent over variations process, temperature, voltage. Stabilizing these delay times requires compensation scheme independent these parameters. this feedback, determine delay error that error generate corrective input back into delay line. This requires method measure delay error control delay time. simple control delay time logic gate vary supply voltage. general, higher voltage, shorter delay through gate.
081202
AN209
FIGURE VOLTAGE-CONTROLLED DELAY LINE (VCDL)
More work required measure delay time determine delay error. easiest method measure delay time convert something more easily measured, like frequency. take output from delay line, invert feed back into input have oscillator with frequency 1/2td, where total delay through delay lines. this case, have voltage-controlled oscillator (VCO) based VCDL (Figure
FIGURE BASED VCDL
precise frequency reference (which not) phase-locked loop could implemented lock frequency reference frequency, giving same precision. This called delay-lock loop (DLL). Other references available silicon world, such voltage references, that calibrated time production very precise levels. Given this, have elements build compensated delay line. Figure shows block diagram DS1135 3-in-1 delay line. circuit (Figure oscillator output back into voltage-controlled resistance biased fixed current source. controlled resistance actually switched capacitor circuit that resistance inversely proportional frequency feedback. frequency increases, voltage
AN209
drops. This voltage compared fixed-voltage reference consisting matched current source fixed resistance (Rref). Rfreq calibrated match characteristics Rref over temperature voltage. output comparator filtered provides VCO's drive voltage. frequency increases, Vfreq decreases with respect Vref, decreasing drive voltage into VCO, reducing frequency. frequency decreases, opposite happens, increasing frequency. stability frequency equal stability Rref. Rref precision reference that stable over voltage temperature voltage. control loop forces Rfreq equal Rref. This control loop also negates changes delay portion circuit caused variations process, temperature, voltage. this circuit alone cannot used delay line. does make stable oscillator circuit used Dallas Semiconductors EconOscillatorsTM. Fortunately, delay cells same piece silicon, have nearly identical characteristics delay cell used (Figure control voltage into VCDL (configured VCO) identical effect these other independent delay cells. even though they operating open loop, control voltage applied them same effect that delay cell configured providing compensation changes caused process, temperature, voltage.
Figure Delay Line (DS1135) Based Delay-Lock Loop Technology
EconOscillator trademark Dallas Semiconductor.
AN209
These individual delay cells daisy chained together make tapped delay line like DS1100, they used independently they DS1135. DS1075 DS1077 EconOscillators uses oscillator section only conjunction with programmable divider chain give customer-configurable silicon oscillator. Combine this circuit with controlling VCO's control voltage full-scale frequency synthesizer like DS1085 produced. circuitry described above patented Dallas Semiconductor (U.S. patent 982, 241, well other patents).
Contact Information: Barry Ross Brian Vasquez John Adams Business Manager (ST&C) Applications Manager Corporate Applications 972-371-4348 <barry.ross@dalsemi.com> 972-371-6486 <brian.vasquez@dalsemi.com> 972-371-6001 <john.adams@dalsemi.com>
Related Data Sheets: DS1023 DS1075 DS1100 DS1135 DS1077 DS1077L

Delay Lines Work Dallas Semiconductor Delay Lines Work? earl

Top Searches for this datasheet

Other recent searches