74LS257 DATASHEET PDF
74LS datasheet, 74LS pdf, 74LS data sheet, datasheet, data sheet, pdf, Fairchild Semiconductor, 3-STATE Quad 2-Data Selectors/Multiplexers. These Schottky-clamped high-performance multiplexers feature 3-STATE outputs that can interface directly with data lines of bus-organized systems. With all but. 74LS datasheet, 74LS circuit, 74LS data sheet: FAIRCHILD – 3- STATE Quad 2-Data Selectors/Multiplexers,alldatasheet, datasheet, Datasheet.
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Ground is still common, but not Vcc. If there’s a doubt datasheer, note that if you use only ohms, a logic output of nearly 5V, minus a Schottky diode drop, divided by ohms is still over 40mA; so I would make it perhaps ohms, and put a 47pF or pF across datasheft resistor so the slew rate at the load doesn’t get too slow.
WDC’s data sheets call for a clock-input rise and fall time of 5ns or better. Home – IC Supply – Link.
This assumes the dwtasheet setup time is met. To minimize the pos. The VFO kind of falls into the category of test equipment to be connected temporarily; so from that perspective, you could connect it only after both the VFO and the SBC are powered up, then press the SBC’s reset button.
Congratulations to your success!! You dstasheet not have the required permissions to view the files attached to this post. It also permits the use of standard TTL reg. Features s 3-STATE versions LS and LS with same pinouts s Schottky-clamped for significant improvement in A-C performance s Provides bus interface datasheeet multiple sources in high-performance systems s Average propagation delay from data input 12 ns s Typical power dissipation: Page 29 of But first, there is still that C Having a separate stable voltage source for the VFO is a great idea.
The problem was entirely the result of a silly error.
I tested the circuit with the 65C02 on a breadboard and it worked perfectly. Fri Feb 16, 8: Anytime the VFO power supply is substantially higher than the SBC power supply which could happen during powerup or powerdown you can encounter unexpected current flow.
IC Datasheet: 74LS257
Mon Aug 06, 6: A very gratifying result, especially given the cycle-accurate constraint. Let’s say the load were 30pF. You cannot 74ls2577 new topics in this forum You cannot reply to topics in this forum You cannot edit your posts in this forum You cannot delete your posts in this forum You cannot post attachments in this forum.
Thanks for all the comments Dieter!
74LS Datasheet Hitachi Semiconductor pdf data sheet FREE from
TTL Here I come. Now here is one of the original objectives of the project as outlined back in Sun Aug 05, 2: You’d definitely want that capacitor across there to prevent that slowing.
Mon Dec 31, 3: This socket goes unused when the TTL CPU is installed, and it conveniently has all the signals we need for wait-stating. Thu Feb 15, 1: Schottky-clamped for significant improvement in A-C. Major milestone, major success – congratulations Drass! Got the timing parameters for 74xx chips from there: I had left off with stable operation at 20MHz, wondering if that could be bettered.
Or add an external input-protection diode Schottky type on the SBC to help the internal diode carry the current. Provides bus interface from multiple sources in. Devices also available in Tape and Reel.
Should be taken into account when trying to run a C64 with a W65C Mon Feb 19, These Schottky-clamped high-performance multiplexers.
For CMOS thresholds at. Previous topic Datashet topic. This 3-STATE output feature means that n-bit paralleled data selectors with up to sources can be implemented for data buses.
Darn, this one is proving to be very stubborn!