LT1720IS8 Linear Technology, LT1720IS8 Datasheet
LT1720IS8
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LT1720IS8 Summary of contents
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... LT1720/LT1721 are ideal for systems where small size and low power are paramount. L, LT, LTC and LTM are registered trademarks of Linear Technology Corporation. UltaFast is a trademark of Linear Technology Corporation. All other trademarks are the property of their respective owners. OUTPUT 17201 TA01 ...
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LT1720/LT1721 ABSOLUTE MAXIMUM RATINGS Supply Voltage GND ........................................7V CC Input Current ....................................................... ±10mA Output Current (Continuous) ............................. ±20mA Junction Temperature .......................................... 150°C (DD Package) .................................................... 125°C Lead Temperature (Soldering, 10 sec) .................. 300°C PIN CONFIGURATION TOP VIEW +IN ...
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... LT1720CDD#TRPBF LT1720IDD#PBF LT1720IDD#TRPBF LT1720CMS8#PBF LT1720CMS8#TRPBF LT1720IMS8#PBF LT1720IMS8#TRPBF LT1720CS8#PBF LT1720CS8#TRPBF LT1720IS8#PBF LT1720IS8#TRPBF LT1721CGN#PBF LT1721CGN#TRPBF LT1721IGN#PBF LT1721IGN#TRPBF LT1721CS#PBF LT1721CS#TRPBF LT1721IS#PBF LT1721IS#TRPBF Consult LTC Marketing for parts specifi ed with wider operating temperature ranges. *The temperature grade is identifi label on the shipping container. Consult LTC Marketing for information on non-standard lead based fi nish parts. ...
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LT1720/LT1721 ELECTRICAL CHARACTERISTICS range, otherwise specifi cations are SYMBOL PARAMETER Δt Differential Propagation Delay PD t Propagation Delay Skew SKEW t Output Rise Time r t Output Fall Time f t Output Timing Jitter JITTER f Maximum ...
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TYPICAL PERFORMANCE CHARACTERISTICS Input Current vs Differential Input Voltage 2 25° –1 –2 –3 –4 –5 –6 –7 –5 –4 –3 –2 – DIFFERENTIAL INPUT VOLTAGE (V) 17201 G04 ...
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LT1720/LT1721 PIN FUNCTIONS LT1720 +IN A (Pin 1): Noninverting Input of Comparator A. –IN A (Pin 2): Inverting Input of Comparator A. –IN B (Pin 3): Inverting Input of Comparator B. +IN B (Pin 4): Noninverting Input of Comparator B. ...
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TEST CIRCUITS 15V P-P BANDWIDTH-LIMITED TRIANGLE WAVE ~ 1kHz V CC 0.1μF 50k + 50Ω 50Ω – 200k DUT 1/2 LT1720 1/4 LT1721 1/2 LT1638 + 100k 100k – + 100k – 100k 1/2 LT1638 NOTES: LT1638, ...
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LT1720/LT1721 APPLICATIONS INFORMATION Input Voltage Considerations The LT1720/LT1721 are specifi ed for a common mode range of –100mV to 3.8V when used with a single 5V supply. In general the common mode range is 100mV below ground to 1.2V below ...
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APPLICATIONS INFORMATION High Speed Design Considerations Application of high speed comparators is often plagued by oscillations. The LT1720/LT1721 have 4mV of internal hysteresis, which will prevent oscillations as long as parasitic output to input feedback is kept below 4mV. However, ...
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LT1720/LT1721 APPLICATIONS INFORMATION The exact amount of hysteresis will vary from part to part as indicated in the specifi cations table. The hysteresis level will also vary slightly with changes in supply voltage and common mode voltage. A key advantage ...
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APPLICATIONS INFORMATION Interfacing the LT1720/LT1721 to ECL The LT1720/LT1721 comparators can be used in high speed applications where Emitter-Coupled Logic (ECL) is deployed. To interface the outputs of the LT1720/LT1721 to ECL logic inputs, standard TTL/CMOS to ECL level translators ...
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LT1720/LT1721 APPLICATIONS INFORMATION 5V 180Ω LSTTL 270Ω 820Ω (a) STANDARD TTL TO PECL TRANSLATOR R1 1/2 LT1720 (b) LT1720/LT1721 OUTPUT TO PECL TRANSLATOR 3V R1 1/2 LT1720 R4 (c) 3V LT1720/LT1721 OUTPUT TO PECL TRANSLATOR 1/2 LT1720 ...
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APPLICATIONS INFORMATION Circuit Description The block diagram of one comparator in the LT1720/LT1721 is shown in Figure 6. There are differential inputs (+IN/–IN), an output (OUT), a single positive supply (V (GND). All comparators are completely independent, shar- ing only ...
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LT1720/LT1721 APPLICATIONS INFORMATION Speed Limits The LT1720/LT1721 comparators are intended for high speed applications, where it is important to understand a few limitations. These limitations can roughly be divided into three categories: input speed limits, output speed limits, and internal ...
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APPLICATIONS INFORMATION The gain and hysteresis stage of the LT1720/LT1721 is simple, short and high speed to help prevent parasitic oscillations while adding minimum dispersion. This internal “self-latch” can be usefully exploited in many applications because it occurs early in ...
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LT1720/LT1721 APPLICATIONS INFORMATION 1000 800 600 400 200 0 2.5 3.0 3.5 4.0 4.5 5.0 SUPPLY VOLTAGE (V) Figure 8. Timing Skew of Figure 7’s Circuit The circuit in Figure 9 shows a crystal oscillator circuit that generates two nonoverlapping ...
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APPLICATIONS INFORMATION Timing Skews For a number of reasons, the LT1720/LT1721’s superior timing specifi cations make them an excellent choice for applications requiring accurate differential timing skew. The comparators in a single package are inherently well matched, with just 300ps ...
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LT1720/LT1721 APPLICATIONS INFORMATION DELAY DETECTOR + Y U1A 1/4 LT1721 51Ω* – R8* 4.53k 5V R9 0.1μF 487Ω* – U1B 1/4 LT1721 + X 51Ω RESULT OF X AND NOT Y ...
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APPLICATIONS INFORMATION Optional Logarithmic Pulse Stretcher The fourth comparator of the quad LT1721 can be put to work as a logarithmic pulse stretcher. This simple circuit can help tremendously if you don’t have a fast enough oscilloscope (or control circuit) ...
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LT1720/LT1721 APPLICATIONS INFORMATION MEASURED 100 1000 t (ns) PULSE Figure 14. Log Pulse Stretcher Output Pulse vs Input Pulse NANOSECOND INPUT RANGE 1 FOOT CABLE CIRCUIT OF FIGURE 12 2V ...
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APPLICATIONS INFORMATION INPUT + U1A 1/4 LT1721 – V REF 100mV FULL SCALE = 1N5711 = CA3039 DIODE ARRAY (SUBSTRATE TO –5V) 1.5k 3.6k 0.1μ 1/2 LT1720 – SKEW 2k COMP SAMPLE COMMAND 2.5k + 10pF 1/2 ...
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LT1720/LT1721 APPLICATIONS INFORMATION The input waveform is presented to the diode bridge switch, the output of which feeds the LT1227 wideband amplifier. The LT1720 comparators, triggered by the sample com- mand, generate phase-opposed outputs. These signals are level shifted by ...
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APPLICATIONS INFORMATION Coincidence Detector High speed comparators are especially suited for interfac- ing pulse-output transducers, such as particle detectors, to logic circuitry. The matched delays of a monolithic dual are well suited for those cases where the coincidence of two ...
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LT1720/LT1721 SIMPLIFIED SCHEMATIC 24 17201fc ...
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PACKAGE DESCRIPTION 3.5 0.05 1.65 0.05 2.15 0.05 (2 SIDES) 0.25 0.05 0.50 BSC 2.38 0.05 (2 SIDES) RECOMMENDED SOLDER PAD PITCH AND DIMENSIONS .050 BSC .245 MIN .030 .005 TYP RECOMMENDED SOLDER PAD LAYOUT .010 – .020 (0.254 – ...
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LT1720/LT1721 PACKAGE DESCRIPTION 5.23 (.206) MIN 0.42 0.038 (.0165 .0015) TYP RECOMMENDED SOLDER PAD LAYOUT GAUGE PLANE 0.18 (.007) NOTE: 1. DIMENSIONS IN MILLIMETER/(INCH) 2. DRAWING NOT TO SCALE 3. DIMENSION DOES NOT INCLUDE MOLD FLASH, PROTRUSIONS OR GATE BURRS. ...
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... FLASH SHALL NOT EXCEED 0.010" (0.254mm) PER SIDE Information furnished by Linear Technology Corporation is believed to be accurate and reliable. However, no responsibility is assumed for its use. Linear Technology Corporation makes no representa- tion that the interconnection of its circuits as described herein will not infringe on existing patent rights. ...
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... C1’s V detector’s 3ns specification is based on a full, legitimate logic high, without the help of a regenerative one-shot. 6 See Linear Technology Application Note 47, Appendix B. This circuit can detect the output of the pulse generator described after 40dB attenuation. 5V 0.01μF 15k – ...