Recent content by jedynakiewicz

Okay, I think that I am sorted. Herewith a reference diagram for anyone else looking for such an answer. I have patched in the terminations for amplifier 2 in the chip. The Maxim note does not give any resistor values - I am presuming that 10K should probably be right? Anyone got any...

I am using an LM324 Operational Amplifier IC to handle the DAC output from a PICAXE. I only need one of the four operational amplifiers on the chip; I am using pins 1,2,3,4 &11. What should I do with the unused pins? If I leave them unconnected I fear that the chip may be damaged by static...

I intend switching some small DC motors (12v 300mA, brushed) using a TIP125 PNP transistor. I note that the internal circuit of the transistor (Figure 1) shows a protection diode across C-E. Would this be sufficient to deal with the inductive load back-EMF from the motor or do I need a...

I need to switch a number of outputs through a driver chip; normally I would use the ubiquitous ULN2803A but in this case I need to switch the high side. Fortunately, before they became discontinued, I bought a number of UDN2981A chips. These are really the high-side switching equivalent of...

That is a most ingenious solution and I can think of several possible applications with similarly-pinned chips where that approach would be most useful, thank you. I have photographed the method that I use with the L298; the pins can be bent carefully using two pairs of fine needle-nosed...

Interference suppression for small D.C. Motors A lot has been written on this forum regarding decoupling ICs and the suppression of interference from small electric motors. The standard 220nF capacitor across the motor brushes seems to work in most cases...but not all. It strikes me that the...

I have been using L293D driver ICs to operate small DC motors. I need to increase the current with some new motors and I intend substituting SN754410 chips for the L293D chips. I understand that this is a direct one-for-one substitute but with a higher current rating. The L293D drivers have...

I routinely use Program Editor but I have just installed the latest version of Logicator because I noted that it said that the latest version has URF/ERF configuration Wizards added. I am unfamiliar with Logicator and I simply cannot locate these wizards. Can someone point me in the right...

Have you got a properly decoupled and stable power supply for the PICAXE chips? Servo systems can be so terribly noisy and really spike up the chips. Perhaps you might indicate your circuit diagram for the power supply to the servos and PICAXE. I think the best way is to run the servos on 6v...

Lots of helpful information in these posts, many thanks. Now can someone just confirm for me that I have the correct understanding of the behaviour of chip antennae? My understanding of the radiation pattern is that the chip antenna is omnidirectional and polarised. I have sketched a diagram...

May I suggest a new command; "EDGE". This would be similar to INPUT but would detect only a rising pulse edge or a falling pulse edge as required. In other words, only a specific directional change in the state of a pin, not the actual state. It would need qualifiers to detect the rising edge...

I have an AXE230 and I would like to incorporate it into an N-Gauge miniature vehicle but the 08M needs 5 volts. The new surface-mount 08M2 would run on 2.4 volts, making the internal batteries very simple to achieve; in fact they are already there. Is there going to be an "AXE231"...

I am rather confused by three conflicting circuit diagrams relating to wiring the infra-red receiver to PicAxe chips. Picaxe Manual 2 (page 112) shows pin 3 connected to 0V by a 4.7uf capacitor and pin 1 to 5V via a 4k7resistor. Page 3 of document axe040 shows pin 3 connected also to 5V...