2
votes
1answer
129 views

What is the function of the given IC?

Which Type of IC is this one ? what is its function
2
votes
0answers
72 views

What components do I need to wirelessly transmit a small signal via Bluetooth? [closed]

So I'm doing a project trying to create a wireless Electrocardiogram (ECG or EKG) system. I built the hardware, connected it to a human subject, and it works perfectly - you can see the heartbeat ...
9
votes
3answers
605 views

Are there any types of DC motors that self-lock themselves?

I have a small DC gear motor which spools a plastic line. Once I've engaged the motor to tighten the line, I want to lock it in place so that the line doesn't unspool. I would then like it to remain ...
3
votes
1answer
626 views

Connecting microcontroller 3.3V output to relay using ULN2803A

I have a need to connect an ARM micro-controller with 3.3V digital output pins to a few 12V solenoid water valves. I figured that I can use a ULN2803A for this task. The internal circuit for each ...
4
votes
1answer
115 views

Can low current/voltage damage ICs?

I'm a total newbie at this, and I'm trying to make my Arduino-mini work on batteries. Is it 100% safe if my arduino (or other components) receive like the minimum current to the point it's about to ...
-3
votes
2answers
295 views

Instructing the Program Counter (PC) to increment [closed]

I am building an 8bit computer from TTL, in regards to the Program Counter, sometimes I may not want it to increment on each clock pulse, with that in mind, how would I instruct it to increment? The ...
-3
votes
1answer
223 views

SAP-1/8 Bit Computer MAR/RAM [closed]

I am looking to develop my own 8 bit computer with a really basic instruction set. I do not know however what the best IC is to be able to perform this job. Could I utilise an Arduino to act as the ...
0
votes
0answers
303 views

SAP-1 (Simple as Possible) W Bus

I'm currently investigating the SAP-1 to build in order to grasp a really good understanding of simple 8 bit computers. There are a few questions that I would like clearing up. What exactly is the ...
3
votes
2answers
200 views

Why are some IC's programmable in circuit, but others aren't?

Why are some IC's programmable while still connected in a system/circuit, but others aren't? What's the determining factor(s) for whether a chip can or cannot? This question stems from my research on ...
3
votes
2answers
181 views

Creating a Programmable ROM Logic / Schematic

I would like to know if it is possible to create a programmable ROM from transistors and logic gates? Or, is it possible to create a type of persistent storage similar to Flip Flops?
1
vote
2answers
438 views

How does the 4017B Decade Counter work?

I am currently looking at a 4017B Decade Counter Data Sheet. As I look at the Logic Schematic for this IC (http://www.ti.com/lit/ds/symlink/cd4017b.pdf) I can see several sqaure boxes label D, C, ...
0
votes
0answers
266 views

Differences between HC-SR04 and SRF04

I'm going to make a project using a PIC18F4550 and a HC-SR04 ultrasonic sensor to measure the level of an open oil tank and want to use proteus to debug the program of the microcontroller, proteus ...
1
vote
1answer
198 views

XOR gate with NAND

I am attempting to build an XOR gate with NAND ICs. This schematic is how I am wiring up the IC (I know the schematic is a little confusing but I tried to construct it best I can). I am ...
1
vote
1answer
133 views

Bottom half of IC appears not working?

I have a NAND logic gate, the top 6 pins appear to be working fine (4x Input, 2x Output) However the bottom 6 pins on the IC appear not to work. I was testing the IC via an LED, connecting two high ...
1
vote
1answer
97 views

What kind of failure would I see in moisture sensitive parts?

I am reflowing a design using an electric skillet. When the uC and LEDs arrived they were in moisture sensitive packaging. They were in sealed bags with moisture indicator cards. After I opened them I ...
-1
votes
3answers
220 views

Reasons of more than one ground pin in L293

Why in L390 they provide four pins for the ground and the heat sink? For heat sink,is only one pin is not sufficient? Here is the datasheet http://www.ti.com/lit/ds/symlink/l293d.pdf
1
vote
2answers
519 views

IC buffer like 4066 with 8 or 16 switches

I have a computer and two monitors. I want to build a device so that I can switch between to monitors. I would use buffers (like 4066) and a microcontroller. Is there any buffer like 4066 with 16 or 8 ...
14
votes
2answers
654 views

How did handheld video games from the 70's and 80's work?

I'm curious about how the early handheld video games from the 70's and 80's worked. You know, those small games with a LCD display with "fixed elements" meaning it was hard wired for one (or a small ...
2
votes
2answers
420 views

Control multiple LEDs using an IC and PC/Linux thru USB

I've already tried to search this topic but all Google results said that this isn't possible. Is there any chance of controlling multiple LEDs using a PC/Linux, through USB? The diagram might look ...
2
votes
2answers
217 views

What can I do as a student to be a better candidate for a hardware design job? [closed]

If you were looking to hire a student still in school for an internship position at a high-tech company (say, Microsoft, Apple, or Google) for hardware design. What kind of skills would you be looking ...
3
votes
2answers
429 views

Identify an IC Found in a Garage Door Opener

Inside a defunct garage door opener I found this IC: I tried searching for 33192C with variations of 'datasheet' and such keywords, but I got routed to the usual datasheet farms who are happy to ...
5
votes
3answers
355 views

Driving LEDs / other small loads with a 74HC06 or similar inverter

I was recently reverse-engineering some firmware (and other bits) from a router, and spotted that the front panel LEDs were driven from a 74HC06 hex inverter gate chip rather than a proper LED driver. ...
2
votes
3answers
532 views

How to identify faulty or Fake (Duplicate) ICs?

I am developing an application on LPC2138. I prepared prototype using a standard development board. After completion, I shifted to final board. But I am not able to download any program my LPC2138. ...
-1
votes
1answer
186 views

Mobile Server Uplink / GPS Coordinate Packet? [closed]

I'm completely uneducated when it comes to more advanced electrical engineering. I understand the very basics. I have over 12 years in software development / programming, but would like to extend my ...
2
votes
3answers
615 views

IC/Microcontroller logic gates

I am a software developer trying to understand how computers work at a lower level. I understand that there is a difference between an Integrated Circuit, a MicroProcessor and a MicroController. A ...
0
votes
1answer
284 views

Frequency modulation and communication between two microcontrollers

I have good progamming skills and concepts on 8051 microncontroller. People suggest me to work on PIC and ARM micro-controllers but I want to make some small projects on 8051 and later move on to ...
2
votes
2answers
536 views

Building and Driving a Stepper Motor

I don't know whether or not I'll actually build one yet, as to do so properly would require ball bearings, metal working, etc and frankly the fund's just aren't available right now(have yet to ...
1
vote
1answer
625 views

Arduino to act as a switch for a remote

I have a wireless remote control for a light. It runs with a 12V battery. It has two mini Omron type B3F momentary ON switches (mini push-button switches). One button is for Light ON, the other for ...
4
votes
1answer
457 views

Can I connect ICs directly together

This is probably answered elsewhere but I can't seem to find it. I have a circuit which uses a Mega8 to drive a couple of ICs as shown in the diagram below. The ISP connectors in the diagram are: ...
0
votes
1answer
615 views

48VDC SLA charger from 12VDC supply design help

I am in the process of designing a 48 VDC (comprised of 4 x 12 VDC) lead-acid battery charger, with an input voltage of 12 VDC. 1W - 2W output is sufficient, and relatively high efficiency with low ...
1
vote
1answer
272 views

Driving a LCD from a Basic Stamp 2 microcontroller

I'm not able to drive a UP018D01 LCD Display (www.ic72.com/pdf_file/u/590916.pdf) with my Basic Stamp II microcontroller. The first step I'm trying to do is to switch ON the LCD backlight. According ...