High eff. automotive buck SMPS chip?

Started by Anonymous in sci.electronics.design8 years ago 8 replies

Howdy, I'm trying to save some heat in an existing product, automotive application. Anyone have a fave buck synch. switcher, Joerg-cheap? ...

Howdy, I'm trying to save some heat in an existing product, automotive application. Anyone have a fave buck synch. switcher, Joerg-cheap? Vin: +12-28v Vout: +5v Iout: 4-5A n: > =90%


Jumpers or low-ohms resistors in SOT523?

Started by Joerg in sci.electronics.design8 years ago 12 replies

Folks, Is a SOT23 "shorting device" available at a mainstream distributor? What would it be called? Pretty much like this but in...

Folks, Is a SOT23 "shorting device" available at a mainstream distributor? What would it be called? Pretty much like this but in SOT523: http://www.semiconwell.com/r_net/zero_ohm_jumpers_swr0j-sot23-3.htm It's a situation similar to what Phil recently had, there ain't enough volts. In my case a moocher winding on a 5V switcher. The load the client has on the +5V may be much lower than ...


Simple half-bridge switcher 25VDC-75VAC 20kHz+ 90 to 500+ watts

Started by P E Schoen in sci.electronics.design8 years ago 6 replies

I have built a prototype of a half-bridge switching supply using a=20 PIC16F1825, an IRS2001 driver, and a transformer that I wound using...

I have built a prototype of a half-bridge switching supply using a=20 PIC16F1825, an IRS2001 driver, and a transformer that I wound using the=20 core, bobbin, and wire from a computer power supply probably about 500=20 watts. The core is 47x47x12mm and N27 ferrite. Here is an image of the=20 LTSpice simulation and output waveform: http://enginuitysystems.com/pix/25VDC-75VAC_25kHz_HalfBridge...


new 30MHz to 300MHz switcher - worlds smallest laptop adapter

Started by Jamie M in sci.electronics.design8 years ago 64 replies

Hi, Here's a new SMPS switcher apparently coming out next year for...

Hi, Here's a new SMPS switcher apparently coming out next year for laptops: http://phys.org/news/2013-12-circuit-laptop-charger-brick.html It apparently has a "power reclaiming scheme" for higher efficiency, would this be conventional sync rectification or some other thing? It looks like power electronics is in for a big (r)evolution once the 300MHz+ designs start to spread! cheer...


ST semi - CHN063AB.

Started by Ian Field in sci.electronics.design8 years ago

Anyone know whether this is a thinly disguised MC34063? Its definitely a switcher of some sort. Thanks.

Anyone know whether this is a thinly disguised MC34063? Its definitely a switcher of some sort. Thanks.


Buck switcher fails when potted

Started by Anonymous in sci.electronics.design8 years ago 52 replies

We're using a buck switcher, LM2574HV-5.0 in SOIC package on a custom PCB. = The load is less than 200mA and the input voltage can vary, but...

We're using a buck switcher, LM2574HV-5.0 in SOIC package on a custom PCB. = The load is less than 200mA and the input voltage can vary, but most testi= ng as been at higher input voltages, around 55V. The IC has a max. input v= oltage of 60V and absolute max of 63V so this should be fine. We were careful about component selection and when possible, went with the = recommended parts in th...


Voltage to PWM chip (similar to class D)?

Started by Joerg in sci.electronics.design7 years ago 127 replies

Folks, Does anyone know an IC that can turn a control voltage into PWM and can handle PWM frequencies in the 50-1000kHz range? Similar to a...

Folks, Does anyone know an IC that can turn a control voltage into PWM and can handle PWM frequencies in the 50-1000kHz range? Similar to a class D driver but has to go down to DC. The changes in control would be restricted to the audio spectrum below 15kHz. The LTC6992 does this nicely but isn't precise enough. Same with 555-style timers or switcher chips. I am looking for better 1% and...


Spice mosfet dissipation

Started by John Larkin in sci.electronics.design7 years ago 8 replies

Is there an easy way to get a graph of mosfet power dissipation vs time, or, alternately, to compute the dissipation within some time window...

Is there an easy way to get a graph of mosfet power dissipation vs time, or, alternately, to compute the dissipation within some time window on the transient analysis? I guess I could do a behavioral voltage source whose output is the product of Id * Vds, and then lowpass filter that. Seems klunky. I'm designing a dumb pure-hysteretic constant-current switcher and applying various st...


Powering ADC off a reference

Started by Fibo in sci.electronics.design7 years ago 34 replies

Greetings, I was wondering if anyone could recommend a precision reference that could also be used to power an ADC. I have an LTC2440 (that's...

Greetings, I was wondering if anyone could recommend a precision reference that could also be used to power an ADC. I have an LTC2440 (that's the part I have to use) it's a 24bit sigma delta, but I only need about 16bits from it. My voltage source is 24V from an unregulated switcher, it has like 100mV ripple. I'm looking at the LM4050, it's a shunt reference http://www.ti.com/product/...


gate driver

Started by John Larkin in sci.electronics.design7 years ago 13 replies

I need a mosfet gate driver, to drive two n-fets in a half-bridge (totem pole) config, 5 volts nom in, with some sort of bootstrap for the...

I need a mosfet gate driver, to drive two n-fets in a half-bridge (totem pole) config, 5 volts nom in, with some sort of bootstrap for the upper fet gate. Switcher output will be around 2.5 volts at 5 amps, so the gate drives don't have to be monstrous. I've been working with LTC4442 on a breadboard, but it's really erratic. Sometimes it's beautiful, and sometimes the gate drive breaks ...


switching power supplies in parallel

Started by Anonymous in sci.electronics.design7 years ago 13 replies

I have two 6V 1.2A power supplies, and I'd like to parallel them to get ~ 2= .4A. Can you safely do that? These are identical manufacture wall...

I have two 6V 1.2A power supplies, and I'd like to parallel them to get ~ 2= .4A. Can you safely do that? These are identical manufacture wall warts, an= d I don't know anything about them other than the ratings and that it claim= s to be a switcher on the label.


Just for fun - Two Transistor LED Buck Switcher

Started by Anonymous in sci.electronics.design7 years ago 66 replies

It's been a while since we've seen ASCII... Fig. 1 ------ R1 Q1 _______ Vin 5.6 2n4403 ...

It's been a while since we've seen ASCII... Fig. 1 ------ R1 Q1 _______ Vin 5.6 2n4403 .-.-.-. 30v> --+-/\/\/-+----+----. .----+---+---' ' ' '-----+----. | | | V / D2| | L1 | | LED1, 3.3W | R2 --- ----- --- R4 220uH +| | NS6W183RT | 470 ^


Any experience with Fairchild FSFA2100?

Started by Joerg in sci.electronics.design7 years ago 13 replies

Folks, Has anyone used the FSFA2100 primary switcher chip? We are seeing some failures upon a "dirty" input power start-up. That shouldn't...

Folks, Has anyone used the FSFA2100 primary switcher chip? We are seeing some failures upon a "dirty" input power start-up. That shouldn't happen because per datasheet it has cycle-by-cycle current limit. https://www.fairchildsemi.com/datasheets/FS/FSFA2100.pdf -- Regards, Joerg http://www.analogconsultants.com/


little pcb-mount CTs

Started by John Larkin in sci.electronics.design7 years ago 83 replies

Anybody know of a source for a small (1 amp range) PCB mount current transformer? Frequency will be around 400 Hz. There are switcher...

Anybody know of a source for a small (1 amp range) PCB mount current transformer? Frequency will be around 400 Hz. There are switcher current sense CTs, but I don't know if they will work that low. Or maybe I could use a shunt and a voltage-mode (audio) transformer. -- John Larkin Highland Technology, Inc picosecond timing precision measurement jlarkin att highlan...


charge pump/boost converter

Started by bitrex in sci.electronics.design6 years ago 57 replies

For a hobby project, I'd like to be able to generate +48 volts or so from +5 volt USB. Current requirements are small, maybe 15 mA or so?...

For a hobby project, I'd like to be able to generate +48 volts or so from +5 volt USB. Current requirements are small, maybe 15 mA or so? I'd like uh, low noise (I don't have an exact spec so this is just kind of existential at this point), so maybe a charge pump would be in order rather than a boost switcher? Does anyone make a charge pump IC that I could feed an external clock to...


dual-supply switcher

Started by John Larkin in sci.electronics.design6 years ago 16 replies

This might be useful for something, maybe: https://dl.dropboxusercontent.com/u/53724080/Circuits/Power/Dual_PS_Buck.JPG

This might be useful for something, maybe: https://dl.dropboxusercontent.com/u/53724080/Circuits/Power/Dual_PS_Buck.JPG


Todays's tronix project, LM2596 switcher as a current source

Started by Jan Panteltje in sci.electronics.design6 years ago 9 replies

Todays's tronix project, LM2596 switcher as a current source. For the big battery loader would it not be nice to have a current source that was...

Todays's tronix project, LM2596 switcher as a current source. For the big battery loader would it not be nice to have a current source that was simple, and made from stuff I already have in the box. The big ebay modules are cheap, but a bit of overkill. Had once (upon a time) made a little test board for the LM2596-3.3V version, that I actually use for any other volts > = 3,3 with the ai


My first switcher

Started by George Herold in sci.electronics.design6 years ago 28 replies

Hi all, Well I get to do a SMPS. There are boat loads of IC's out there and I'm looking for recommendations. (I better go re read AoE3) I...

Hi all, Well I get to do a SMPS. There are boat loads of IC's out there and I'm looking for recommendations. (I better go re read AoE3) I need a number of output voltages. +15V, +5V, -5V, -15V. and +24V. maximum current of 0.5A on any one. My current plan is to run the whole thing from a 24V wall wart or brick. Price and size is not too much of an issue, I guess fewer external pa...


Sensing 300A on a SMD PCB

Started by Anonymous in sci.electronics.design6 years ago 65 replies

It looks like there's a requirement on my horizon to make 3kW from 11V d.c., which promises to pose some interesting challenges. One is...

It looks like there's a requirement on my horizon to make 3kW from 11V d.c., which promises to pose some interesting challenges. One is sensing that much current on an SMD PCB. Keeping sense resistor dissipation below 1W means Vsense


Filtering switcher noise

Started by bitrex in sci.electronics.design6 years ago 15 replies

I'm putting together a little 4-> 1 active audio mixer circuit for a friend of mine. The circuit is basically just RC RF filter on the...

I'm putting together a little 4-> 1 active audio mixer circuit for a friend of mine. The circuit is basically just RC RF filter on the input, dc blocking capacitor, potentiometer, then into an active summer and a "zero impedance" output stage for driving cable that has a capacitive feedback loop to keep the opamp stable and then a second feedback loop around the output resistor for st