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### How does the CMRR of difference amplifier ICs change over time?

When designing precision analog circuits, I often come across parts which seem to be more than accurate enough for my purposes, but where the datasheet does not specify how key parameters will change ...
248 views

### Digital data coming out of a cell phone headset mic?

I want to connect a sound board / mixing console / whatever-you-prefer-to-call-it to the headset jack of my Motorola Android phone. I know the typical TRRS pinout of Left/Right/Ground/Microphone, and ...
494 views

### Unable to get bootloader working on custom PCB with AT32UC3L

I have designed a PCB for a client recently, everything is fine with the hardware and software (application is working as it is supposed to). Now we are facing the need to update the program inside ...
141 views

### Very intermittent power MOSFET failure

I am working on a very spotty motor failure (I am not the designer). We have a wound armature which is switched by power MOSFETs. These are driven by a FET totem pole type FET driver. When the ...
347 views

### Signal Flow Graph for electrical circuits

First of all, sorry if my English is not the best. I am a student and my question is about finding the signal flow graph for a simple circuit. I found the above formula for a $k$ node having ...
198 views

### NOP instruction after branch on ARMv7 Cortex M3

I'm interested, why for Cortex M3 microcontroller (stm32f103) compiler sometimes generates a NOP instruction after branch. And why it sometimes doesn't. For example: ...
414 views

### Miniature wireless distance sensor

I am novice in electronics, so please bear with me. I am searching for a small distance sensor (as small as possible) that I can use to measure a distance between 0 and 30 cm precisely (precision ...
171 views

### Implementation of AES algorithm using Systolic architecture

I need to generate a VLSI Systolic array to implement the AES encryption algorithm with key length of 128 bits. Following are the possible ways : Systolic for Key expansion Systolic in MixColumn ...
83 views

### How to implement critical sections on ARM Cortex A9

I am porting some legacy code from an ARM926 core to CortexA9. This code is baremetal and does not include an OS or standard libraries, all custom. I am having a failure that appears to be related ...
48 views

### USB multiplexer - swap pins?

I want to use the USB 2.0 multiplexer TI TS3USB221ARSER. But on the PCB the D+ and D- pins of one connection are crossed (see attached image). Is it okay to change the D+ and D- pins on all sides of ...
79 views

### Is it possible to determine load on a stepper motor when stopped

Is there a way that the torque on a stepper motor can be determined without some kind of additional force sensor. Additional electronics such as current shunts etc would be acceptable. I would like ...
93 views

### Secure signals on boot time to prevent unwanted operations

How can I be sure that at boot time my module won't get random values to it's control signals and write to an address* before I reset the module? *(or anything that shouldn't be done before reset) ...
148 views

### Calculating current draw from a battery using voltage and time information

Is it possible to work out the current or power a device is drawing/using, based on the following information: Maximum capacity of a battery (48 Ah) A table of voltage readings over time (starting ...