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ADE7933 contains an isolated DC-DC converter (Page 82). The control uses ~1MHz PWM signal with unknown rise time, but assuming something like 10ns, most of the energy would be contained in the 35MH...
I have designed a two-stage power supply and control power circuit. The design allows the entire system to be powered and controlled using a single external push switch (when pressed, it is shorted...
I need to interface the NTC thermistor with the SAM D5x/E5x microcontroller. During my research, I came across two common circuit configurations for NTC connections: one where the NTC is connected...
I own a significant amount of male (non-PD) [1] USB-A 2.0, Lightning, and (30-pin) Dock adapters, all of which adapt to female USB-C 2/3[.2]. I never considered these to be non-conformant. However,...
Old fashioned p-n junction devices suffered from a voltage drop (0.6V for Si, 0.2V for Ge, if I remember correctly). FETs and CMOS were the latest highlight back then, and highly prone to be destr...
I have a circuit which reads from an electrochemical sensor IC. The block diagram of the circuit is given below. It contains two voltage regulators for powering the AVDD and DVDD of the ADC. F...
I am using this MPU SOM Module and this NAND Flash device for storing the boot image. I will also use a 4-bit SD card interface with the MPU for data logging. I’m reviewing the MPU datasheet (link...
May I know how to convert mAs to mAh? I have a chip operating at 3.3 V. Its standby current is 0.00085 mA. In one day, the chip is active for only 4.24 s. To calculate the standby energy consum...
The PCB in question is the controller in a monitor (Samsung model U32H850UMN). I noticed arc-shaped cutouts around all mounting holes. The mounting screws are approximately M3 self-tapping for sh...
I’m working on a throttle interface circuit for a BLDC motor controller using an STM32 MCU, and I would like some suggestions for two things — 12 V sensing and hall sensor input protection. The th...
I’m using an N-channel MOSFET (SSM3K15AFU,LF) to drive a 5V RGB LED (Common Anode) that’s mounted off-board and connected via a 12-inch cable. The LED has an internal resistor and draws about 20 mA...
I’d like to discuss how to report errors from C functions up the call chain. Consider firmware which communicates to handful of external peripherals (say over I2C and SPI), then validates the data...
I’m running into a CAN bus termination issue in one of my designs and wanted to get some opinions on the best way to handle it. Setup I have a master controller made up of two PCBs connected in a...
I recently read the accepted answer here, by Olin Lathrop: Decoupling caps, PCB layout It talks about preventing an IC from acting as a center fed patch antenna by keeping the high frequency curre...
The circuit shown below is used on one of my PCBs to switch the VBAT supply for the RTC, ensuring timekeeping continues whenever the main supply (VCC) is unavailable. Circuit Operation Under ...
Capacitors are expected to obey ${\displaystyle C={\frac {Q}{V}}}$ very closely, so computations in RCL-networks can be done assuming impedance to be $j\omega C$. On the other hand, batteries (rec...
There is a plan to do PDN decoupling simulation for the KSZ9897RTXI power rails. It has various power supply like 1.8V, 2.5V& 1.2V. While doing the simulation, what is the maximum frequency ran...
PLL lmx2491 have OSCin pin to apply reference clock on it. It said it is differential. One famous differential is LVDS. It does not tell anything about it's compatible logic standards. It said: ...
This is VBAT switching circuit installed in one of my PCB for Timekeeping when VCC is not present. The switching circuit is working as expected - when VCC is present, the current flows from D3 t...
From my earlier post Controllable Enable/Disable Buck converter circuit, I have updated the design and built it on a breadboard. It works as intended. Circuit Operation - Default: When the batt...
I am reading this IEEE paper which explains the modified buck boost mode operation . I am failing to understand the current paths and equations given by the author for buck mode. based on ...
We perform a test on this device where the regulator input power is enabled with an 8A load connected to the output, while the device itself remains disabled. We then drive the EN pin high to enabl...
I’ve got a simple circuit board where a PCA9554 is controlling the a switch MIC94090YC6. There’s a 100kΩ pull-down resistor. A GPIO pin on PCA9554 is an input on power-up. The leakage current fr...
A microcontroller can be modelled simplistically as a broad band current source/sink. For example, when the microcontroller wakes up from sleep mode and goes into an application mode where many of ...
I am working on the motor controller interface board with a 48 V battery connected (58 V max), the board should remain OFF (no 12V should be generated) when battery is plugged-in, until the user ta...
We’ve been working with the this boost regulator and set it up according to the attached schematic. To minimize power consumption, the approach was to enable the boost once every 31.25 ms: we pull ...
I am interfacing this gas sensor to the ADC of TI CC1352P. May I know can I directly connect the output of this gas sensor to ADC (I mean after the gas sensor output I will keep an RC circuit with ...
The typical GPIO protection circuit can be seen here: In most articles online this type of protection just boils down to 'excess current is dumped into the VDD rail'. However, where does it actu...
I am designing a gas sensor system for an IoT application. My system contains different gas sensors(at present 8 nos).The sensor data swill be connected to a potentiostat IC and this IC will be con...
The below image is taken from this refrence design. May I know why the two zero ohm resistors are used.
This is a coninuation of a question I previously asked here. We made the proto board and it is working in low speeds.The complete circuit is given below. Let me show the wave-forms at each sect...
I designing an electrochemical sensor readout using Ad5941.The LDO used for powering the ADC is ADM7155. In the reference design all the capacitors and resistors used are 0603 package.In my design...
I am using AD5941 in my design. The power section of its analog domain (AVDD) is given below. It is obtained from the reference design. You can see the schematics, BOM etc in bottom of this page. ...
I am working on a digital output concept that I would like to have the following characteristics: Output voltage: 5V Controllable by the uC from 3.3V power supply I would like to be able to sw...
I will be using this ADC in my design. It has two power rails AVDD and DVDD. I am planning to use Two TLV75533PDBVR will be used one for AVDD and other for DVDD. May I know this LDO is good choic...
In this schematic of an SSL G dynamic compressor clone, the input of the channels has this symbol that looks like: --- + | ---| |--- | --- What component is this?
I want to use ADG726 multiplexer for an application where the multiplexer inputs could have potential on them before ADG726 is powered up. Seeing that ADG726 is a CMOS device, it seems it might be ...
A taper pad is a resistive attenuator that maintains impedances on both ports and provides a specific amount of gain-loss ($A_{12}$): - I have derived formulas for each resistor (that I know to ...
I am using AD5941 for my measurements from different sensors.I will be making a breakout board such that in my board I will be providing pads for connecting the sensors and the output of AD5941 wil...
I am making a breakout board which contains 4 hall effect sensors from paragraf.The sensor P/N is EGHSX03Q02 .My schematic is given below .Like this 4 sensors placed in the pcb. These sensors are ...
In the following series LC circuit , maximum input current (IL1) reaches to 321mA in the simulation which is decided by V1/2 x π x f x L1 (f being resonant frequency). why total impedance seen by ...
for the past four years, i set the humidity level of my resmed airsense 10 to 6 out of 8. circled in red below, the hot plate heats up. it's hot to the touch. but all of a sudden, a few days ago, t...
I am designing discrete IrDA receiver using a TIA and a comparator. My initial circuit is given below. I won't be using a BPF after the TIA as given in the MAX3120 Functional block diagram. The out...
I have built an ECG amplifier that uses an instrumentation amplifier and a driven right leg circuit to attenuate 50 Hz common mode voltage stemming from the body. A portion of the circuit is seen b...
The below image is taken from Analog Devices design note DN1045. what is the use of M1 and M2? What is the use of REF and D1?
This is an expansion on Biasing a differential opamp input post. Olin pointed out that gotchas can be in the implementation, so I will provide the circuit and design specifications as well as my re...
I have a differential signal source and a single source amplifier. The source has 2Vp-p signal. I wanted to center the differential signal around 2.5V, so I came up with the following circuit: S...
I am using OPA859-Q1 in one of my applications. It's supply voltage is 3.3V,single supply operation.I am confused about is output swing when operated from 3.3V supply Is the maximum swing is 2.4V ...
I am designing a TAI using this tool from Analog devices. The circuit diagram and it's frequency response obtained from the design tool is given below. Circuit Diagram: Frequency Response I ...
Came across this apparent bracket hanging on a communications line. There is one every comm midspan for about a mile. I looked through historical streetviews and they've been there at least since 2...
