Date: 2002-09-11 12:46:28
> Thus: IC2-reg. out---IC1 (high side switch)--coil (16ohms)---gnd > \--gnd \--+C1 (6800uF)---gnd > \--(-) D1 1N4004 (+)---gnd (for coil kickback) The diode must be parallel to the coil. Then what puzzles me is the fact that you mention 32 Volt. IC2 can source 500 mA. 500mA * 16 Ohm = 8 Volt. I know coils have a minimum Voltage/Current otherwise they won't hold whatever they are supposed to hold. > I need "boost" with C1 to 2A for 100ms, and > T=RC=.1088, about 100ms. That was years ago but my instinct says it doesn't work like this. Let's theorise. If I'm wrong, anybody please correct me. F = Cb/V. This means that with 6800uF C1 contains 0.0068 * 32 Cb electrons. A = Cb/sec. So the moment you connect 16 Ohms to C1, a 2A current will flow. But because there ar electrons flowing away, the voltage over C1 will drop and thus the current will drop. This calculated T value means that the voltage has dropped to about 30% (????). Keeping the Hold-voltage in mind, you have less then 0.1 second. > how long it takes to charge.. 0.0068 * 32 / 0.5 = 0.4352 sec. maximum. But the voltage drop won't be 32V but much less. So the time is shorter. > and also if this is safe to regulator. That depends. If it has a build-in current limiter, then the current is restricted to the 0.5 A used in the calculation. If not, it will supply much more current. Loading time is less but it could damage the regulator. > Also, can gnd be shared with C64, If not using opt-couplers, you have to. > or does some kickbacks leaks through? I presume you steer the switch with one of the I/O-pins of the userport through a resistor. Use diodes to short surpluss Vcc and Vss. Then make sure the C64 is connected to GND of the circuit at only one place. -- ___ / __|__ / / |_/ Groetjes, Ruud \ \__|_\ \___| http://Ruud.C64.org Message was sent through the cbm-hackers mailing list
Archive generated by hypermail 2.1.4.