Has anybody run across a small thin-client style case for a micro-ATX motherboard? All it needs to hold is the motherboard and a slimline...

Has anybody run across a small thin-client style case for a micro-ATX motherboard? All it needs to hold is the motherboard and a slimline optical drive. No hard-drive, no power-supply, no expansion cards. All of the "normal" pc cases I can find are huge and include power supplies and drive bays I don't need/want. -- Grant Edwards grante Yow! They don't h...

I'm going to design a board with an embedded USB Host connector (managed by Atmel SAM D21 MCU). I will use that connection only for data...

I'm going to design a board with an embedded USB Host connector (managed by Atmel SAM D21 MCU). I will use that connection only for data communication with a smartphone or a pendrive. I don't need to recharge the battery of the smartphone. Of course, I need to supply the pendrive. On my board I have to generate a +5V rail only for the USB, but I don't know what is its requirement. Co...

Been doing a lot of stuff recently that requires 3.3V and 12V at moderate currents. The simplest commodity way to do this seems to be a PC...

Been doing a lot of stuff recently that requires 3.3V and 12V at moderate currents. The simplest commodity way to do this seems to be a PC power supply. The 24 way ATX connector is a bit clumsy and you only get one per PSU, so it seems simpler to use SATA connectors as a handy ecosystem of 3.3/5/12v power at up to 4.5A per rail. A scattering of these provides the necessary few hundred watt...

I am looking at designing a new product which will use a external DC power supply and because it has USB ports I was thinking of using a...

I am looking at designing a new product which will use a external DC power supply and because it has USB ports I was thinking of using a 5V supply and therefore a mini or micro usb type charger psu and am not sure which one I should go for and what the maximum current capability of the connector is. For some chargers it is 1amp at 5V but I have found at least one supply rated at 5V 1.8amp. Mo...

hello everyone, I have a RS485 based slave relay driver with 8 relays. The relays turn on at logic 0. Since the 89C51 has all ports as HIGH...

hello everyone, I have a RS485 based slave relay driver with 8 relays. The relays turn on at logic 0. Since the 89C51 has all ports as HIGH during reset, my relays should remain off. The problem that I am facing is that when I turn the power supply on, all the relays turn on momentarily and then back off. Is there a race condition during which the microcontroller is not gaining control of ...

In most DIY stores you can find these cheap Chinese digital timers to turn you lamps or appliances on at specified time. The thing I'm wondering...

In most DIY stores you can find these cheap Chinese digital timers to turn you lamps or appliances on at specified time. The thing I'm wondering is, how do they power the digital circuitry from 110VAC in a device costing only $5-$10? Are they using a transformer or are they directly powering the digital circuitry from the AC voltage?

Perhaps someone with more electronics experience than myself can give me an idea of roughly what sort of power supply I need for the...

Perhaps someone with more electronics experience than myself can give me an idea of roughly what sort of power supply I need for the following scenario: I am looking to power: 11 PIC16F690 microcontrollers which run on +5V 1 cold cathode light which runs on +12V (these are the specs given: Input voltage of inverter: 12v, Output voltage of inverter: 680v, Current draw: 5.0mAv) 1 +3.3V acce...

I have an fx2 device .I have developed a firmware for it . When I download the firmware the device takes a long time to enumarate or some times...

I have an fx2 device .I have developed a firmware for it . When I download the firmware the device takes a long time to enumarate or some times it goes a known device .Some times it quickly enumarates. Is the power supply current has got something to do with the enumaration process. The enumaration process is getting distrubed some how. I appriciate some help thanks in advance punitha

Hi, I have to design a printed circuit board for a high-voltage environment. Hence, the "ground potential" of the board has to be on 4 kV. Du...

Hi, I have to design a printed circuit board for a high-voltage environment. Hence, the "ground potential" of the board has to be on 4 kV. Du to the fact that the absolute potential values don't matter, one could say that the 2 kV are virtually my ground potential. The problem arises by reason of the power supply. I have to power my board with 5 V and for the mains adapter ground is r...

LPC3180 is a ARM926EJS core which uses a 1.2V for the core, sdram, etc, and 1.8V/3.0V for IO. What power supply/regulators would be...

LPC3180 is a ARM926EJS core which uses a 1.2V for the core, sdram, etc, and 1.8V/3.0V for IO. What power supply/regulators would be recommended? Would a single regulator be recommened to achieve these multiple voltages? And how? Thanks.

Hi, does anybody know how to carry out In-circuit Tests of Operational Amplifiers? for the sake of knoledge: In-circuit tests are carried...

Hi, does anybody know how to carry out In-circuit Tests of Operational Amplifiers? for the sake of knoledge: In-circuit tests are carried out by ATE machines with the target unpowered (i.e. no power supply) I read many Teradyne's articles but couldn't find anything useful. thanks for any help, Enrico

Hello All, There is a board with BlackFin BF-537 DSP. We are not using the RTC which is built in BlackFin. I want to disable the RTC to avoid...

Hello All, There is a board with BlackFin BF-537 DSP. We are not using the RTC which is built in BlackFin. I want to disable the RTC to avoid any unwanted activity. There is no way to disable the RTC by software. The RTC has the separate power supply input (VDDRTC), and the pins for connecting a 32k XTAL (RTXI and RTXO respectively). The datasheet says nothing on this matter. The customer ...

Does anybody make a cheap single-board computer with microcontroller and LCD display, like an AVR Butterfly except that the LCD is easy to use? ...

Does anybody make a cheap single-board computer with microcontroller and LCD display, like an AVR Butterfly except that the LCD is easy to use? The Butterfly's LCD is segment-addressable and if you want digits or characters, you have to create them yourself. A 5.0-volt power supply (instead of the Butterfly's 3 V) would also be handy since I have to have 5.0 V for the equipment to whic...

Hi, I'm looking for an embedded board with these minimum caracteristics : - maximum size 150x150mm - low consumption : less than 1A with a...

Hi, I'm looking for an embedded board with these minimum caracteristics : - maximum size 150x150mm - low consumption : less than 1A with a 5-7V power supply - one (or more) i2C link - a free RTOS running on with free tools (to compile, download, ...) eCos would be the better. - one usable (not only for programming) RS232 link with a DB9 connector A do not need a powerfull CPU, ...

Having problems with gr64 transition from gr47 I design primary cell battery powered equipment large volume and have had nothing but trouble...

Having problems with gr64 transition from gr47 I design primary cell battery powered equipment large volume and have had nothing but trouble moving to the wavecom gr64 below have been my issues 1) Power supply -Power requirements are much more challenging than gr47 I no it's class10 not class8 but even so after changing in firmware still is not as easy as gr47 had to do mental gymnastics to ove...

Hello, I have a question about driving an LED with a 7406. Basically I have an MCU going into a 7406 inverter going into an LED going to...

Hello, I have a question about driving an LED with a 7406. Basically I have an MCU going into a 7406 inverter going into an LED going to a resistor R and that going to a 5 V power supply. All in series, and I'm trying to find the value for R that would make this thing work.... here's a sketch of what I'm talking about (this is my first time skecthing on notepad) ...

Hello, In my next uC design I need to check periodically battery and uC temperature and battery and power-supply voltage. I do not have a...

Hello, In my next uC design I need to check periodically battery and uC temperature and battery and power-supply voltage. I do not have a native I2C nor 1Wire on the uC wherever CAN or SPI or some IOs are available. What I prefer would be a kind of simple 2wire interface to some small and handy sensors. Some recommendations ? Are there some don't use sensors? Thx, theAdib. -...

Hey all, I'm in a microcomputer hw/sw class where we are building a microprocessor board using an 8088. I wire wrapped the clock circuit and...

Hey all, I'm in a microcomputer hw/sw class where we are building a microprocessor board using an 8088. I wire wrapped the clock circuit and the reset circuit before testing it with the 8088 in its socket, and all seemed to be fine (voltage tests, and frequency on the clock). When I put the 8088 in its socket I was getting a short between VCC and Ground on the power supply. When I remove...

may be this is a bit off topic here but I bought a 3 year old D-Series lattitude leasing laptop D600 in Ebay. My old notebook had a 2 pin...

may be this is a bit off topic here but I bought a 3 year old D-Series lattitude leasing laptop D600 in Ebay. My old notebook had a 2 pin power connector and the switching supply worked down to 12 Volt. Only battery charging was disabled if power supply was not 18 Volt. From this reason I always used a direct 12V supply in my car without step up converter. I tried to do the same with my D-...

Hi, Please may I ask what the arrangement is when you see a single LED powered straight off of a mains power supply without any transformers...

Hi, Please may I ask what the arrangement is when you see a single LED powered straight off of a mains power supply without any transformers or switch mode circuitry? In other words, totally uninsulated or regulated. I have an old computer with an external hard disk which needs about 30 seconds to spin-up before the computer. With a small timing circuit, 555, or using a PIC even (have ...