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    Sourcing hall effect current sensor from Honeywell Sensing and Control

    I've managed to find a really nice hall-effect type linear current sensor package from Honeywell Sensing and Control. Its the CS series and has the hall-effect sensor embedded into a ring-concentrator, all in a nice package. Trouble is - I'm having trouble finding anywhere that can get me one...
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    Interfacing hall-effect sensor to embedded CPU

    I'm trying to interface an Allegro A1360 half-effect sensor to a TI MSP430 CPU. The A1360 is a 5V device whilst the MSP430 operates from a 1.8V to 3.6V supply. The MSP430 has onboard ADC, but the analog input pins have an absolute max rating of VCC + 0.3V. I have both 3.3V and 5V regulators on...
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    DAC with SPI recommendation

    Can anyone recommend a DAC with SPI. 10 or 12 bit would be good. It will be driven by a 3.3V TI CPU. Analog output would be 5V min, but up to 10V would be good. Also, if it has an evaluation PCB option that would be a good bonus. Thanks.
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    DC circuit breakers rated >63A?

    Anyone know of anywhere I might get hold of a DC circuit breaker rated higher than 63A? We are currently using the Teresaki 4500 series C63 but want to go higher. Yes,  I know it's a high current but those of you who know me will know why!!!
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    Using electro-plating rectifier as a low-voltage high-current power supply

    We've been looking for a low-voltage high-current power supply for our lab to put between 200A and 1000A through a superconducting coil with inductance of 50mH. Total resistance of the load will be around 0.1 Ohm. The only thing I've been able to find so far is an electro-plating rectifier...
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    MOSFETs with built in reverse current diodes

    Alot of MOSFETs come with a built-in diode across the source and drain. The attached diagram outlines what I mean. I would like to confirm that the purpose of this diode is to allow the MOSFET to handle reverse current to flow. I know this question might sound really dumb, but I'm not an...
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    2V high current power supply for homopolar motor

    I need to design a power source capable of delivering high current (maybe 200 or 300A) at only 2V. I thought I may be able to use TIs TPS40180EVM module - it has a lower current rating that I'm after, but you can stack them in a modular fashion. However, I wondered if anyone had any better...
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    H-bridge using only n-channel mosfets

    I have created an H-bridge PC with 4x floating gate drivers and 4x IGBTs (see attached schematic showing half of h-bridge). It works very nicely but I would like to replace the IGBTs with n-channel MOSFETs. However, all the H-bridge designs I've seen use n-channels on the low side and...
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    Evaluating total energy usage from just DC voltage and current

    I'm trying to calculate the total energy usage of a dynamic system that is powered by a bank of lead-acid batteries. My method is simple - log current (using current clamp) and voltage across the battery then post process the logged data - a) For each sample point, Instantaneous Power = V*I...
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    Evaluating energy usage in an H-bridge motor control system

    I use an H-bridge to control a hybrid electric motor and I'm trying to calculate the efficiency by comparing energy used to energy delivered (measured by a torque transducer). I am capturing the voltage and current output of the H-bridge as it flows into to the motor. As you might expect...
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    Sourcing ACS758 hall effect current sensor

    Any good suggestions where I can get hold of the Allegro ACS758 hall effect current sensor in low quantities with short lead times? I'm in Australia, but shipping costs aren't important. I've already tried RS, Farnell and Digikey - all out of stock and long delays before new stock.
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    Problems with DC/DC converters in isolated H-Bridge design

    I am pulling my hair out since I keep destroying the Murata NMC1215SC DC/DC converters in my CPU controlled H-Bridge design. There is no obvious signs of damage such as heat or smell, they simply stop outputting +/- 15V. Testing out of circuit against a reference device shows they truly are...
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    Sourcing high voltage isolation switch for 150V @ 40A

    Any ideas who might be able to supply a high voltage isolation switch capable of handling a constant 150V @ 40A?? The Jaycar SF2245 ones I selected weren't up to the job and began to melt (I thought they might!!)...
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    Advanced Battery Technologies

    I've recently been doing some work with lead-acid batteries. As most of you know, these things are nuts in terms of the amount of power they can deliver - effectively they are a power supply that can deliver hundreds of amps in a small space of time. The upper limit is only defined by the limits...
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    Cooling a resistor load at 6 to 10kW

    I have some resistors to cool that I presume are going to get rather hot!! I am using 6x wirewound resistors in parallel to create a 3.75 Ohm load for a 150V source, hence generating 40A and 6kW. Later I may up the voltage to 200 so I need to spec the cooling for a max of 10kW. Each wirewound...
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    Isolated ground planes on a MCU controlled high voltage IGBT

    I am putting together a PCB that has a CPU to control the on-off state of a high power IGBT. There are two power supplies associated with this: 1) A 24 DC lab PSU that is regulated on the PCB to both 5V (CPU) and 15V (TC427 MOSFET driver) 2) A meaty 150V / 40A DC PSU that flows through the...
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    Controlling IGBTs via a microcontroller

    Anyone have any suggestions how to drive an IGBT via a microcontroller? I'm trying to drive a STGE200NB60S with an Atmel AVR CPU. The AVR can run at both 3.3V and 5V and the gate threshold of the IGBT is 3V, so in theory I could just connect up an go. But, i cant help thinking that it can't be...
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    Current Limiting Technique

    I am setting up a brief experiment that involves a switch an array on twelve 12V lead-acid batteries into a test inductor load at 150V with a limited 40A current. This test will only be conducted for about 10 seconds and I dont want to spend too much time/effort worrying about current limiting...
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    Switch selection for high-power H-bridge

    I'm trying to design an H-bridge that can control the output polarity of an electromagenetic coil with inductance of around 50mH and very low resistance. The source voltage is around 150V at 40A and hence the design and the switch selection aren't trivial. The timing constraints make things...
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