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407 Threads found on Source Sink
can anyone give suggestions regarding minimising settling time in a programmable current source/sink?
Hi i want to desing 20mA constat current source/sink circuit. My supply is varying from 2.2 - 3.4 Volts. Can anyone help me to design the same? how can i maintain constant current throughout this supply range its urgent please help me thanks ~niks~
According to SGS Thomson Microelectronics: IO DC Output source sink Current Per Output Pin ? 35 mA Regards, IanP
Hello! I'm not sure that I've chosen the proper forum section for this topic, sorry if I'm mistaken. Please explain me what is the "source/sink output" current (how to measure it and how to simulate it using SPICE) of I/O cell? As far as I understand it is just a DC output current via resistor connecting the output with the ground. What I reall
Hi everyone,I want to make a programmable current source (or current sink,depending on a digital signal) to provide me 0 to 10uA,10 bits resolution,but i am a beginner and i don't have a clue...Can anyone help???
CMOS inputs have high impedance and don't sink current. Cyclone II has absolute maximum ratings of 25 mA source and 40 mA sink per I/O pin. In addition there's a limition of 240 mA per power pair (8 respectively 12 pins). Drive strength is programmable, the highest refers to a 24 mA class (24 mA with respective min/max Voh/Vil). This also (...)
UPF 2.0 LRM where source and sink options being explored where user can write the power-intent with the help of supply-sets. It is seen that for set_isolation (UPF command which is used to specify isolation strategy) and set_retention (UPF command which is used to specify retention strategy) commands, source and (...)
I need a design hint for a adjustable current sink or current source. I want to control the current through a solenoid (hydraulic control). The current must be adjustable by a voltage (DAC). It should be a closed loop control. The current is in the range from 50mA to 1500mA. The supply voltage is 28V. It should be a switched mode Design. Hope I
Hi all I have to use a constant current,but I'm not sure current source or sink is suitable, what should I take care. Or which one I can use, and why? Thanks a lot ------------------------- chmr
Use the PC port to pulse the led. Control the mark:space ratio to control the brightness OR Use the PC port with a D to A converter (but check that the converter can source/sink the required current first).
For Port 0 and 2 in Bus Mode when addressing external memory, you can count on 8mA source at a minimum of 2,4v output. If you want to deliver outside more than 8 mA you can be sure that the output voltage will significant decrease. Which is not your goal if you want to keep compatibility with a TTL input which needs minimum 2.0v in order to be re
I think it is because there are two more current sources.
I think 3 bits are basically used for precision you have to source /sink the current based on this 3 bits used for correction in charge pump voltage . Simple way is to based on the precision source/sink current needed you can mimic your charge pump circuitry carrying small precion current .you can have a resistor based 3 (...)
Hello all, I need to design accurate 1A current generator to drive 1 to 10 series connected high bright LED from 48V DC source. Any ideas? Aslak
suddenly think of something...can someone clear my doubt...all regarding 8051 question... 1.what is the meaning of "port1 output can sink/source TTL input?i understand that when 1 are written to that port 1,they r pulled high by internal pull up...but y must be internal pulled up in order to use as input...n what is the meaning of source (...)
I am wondering if there is a chip to generate dc current sink in pcb. The nantional LM334 chip can only be used as a current source. Thanks.
The output of the Parallel Port is normally TTL logic levels. The voltage levels are the easy part. The current you can sink and source varies from port to port. Most Parallel Ports implemented in ASIC, can sink and source around 12mA. However these are just some of the figures taken from Data sheets, (...)
Have a look at these CMOS buffers: Also, to increase output source/sink current you can parallel CMOS buffers/gates .. Regards, IanP
555 has source/sink current of up to 200mA so you should be able to drive your motor directly from its output (pin3) .. Option1: you can use 555 in monostabile configuration (see picture below) and adjust time in such a way that the motor does only 1 turn .. Other option will require some sort of shaft encoder build around optocoupler or a switch
Be very careful remembering which to use under which conditions, as reading the wrong register is the cause of more than a few beginner program problems. PortD is primarily for controlling the port when it's configured as an output (DDRB == 1) As setting portb will change it from sourcing to sinking curent. When DDRD == 0 (set to input) portD contr
one solution: Put one NMOS name M4 such this: M4 source to M2 source M4 gate to M2 gate and to M4 drain and add one resistor or some network to prduce constant curent to M4 eg. one resistor between VDD and Q4 drain
yes, 1. check deadzone. 2. check mismatch and leakage of source/sink. 3. are u sure it's locked? loop isn't unstable? 4. I think PLL need this small phase different keep it in "locking".
Hi You are right for sinking current you consider Iol and If of the led as for Io source you consider Ioh and also If of the led ( of course with a factor of safty ) but the output of the c mos series will not satisfy the required curent to light the led satisfactorily so use a buffer ( for example a high gain transistr with a resistance in base
I think the following book should help you in designing the W/L of an output stage. I used Class AB with floating current source. Roubik Gregorian, Introduction to CMOS Op-Amps and Comparators, John Wiley & Sons, Inc., 1999. I would also glance at Grey & Meyer. Srivatsan
hi cdc it could be a latchup, but it depends on what's connected to it. If it's I/O is connected to a couple of loads that source/sink a high current and the firmware froze with those I/O active, it could lead to an overheating. However, you must make sure that the MCU can withstand the environmental conditions it will be in and that it will
Goto: and take a look at "Basic Properties of some TTL Families" .. If, for example, "0 Level Input Current" for each TTL input is 1.6mA that means that the microcontroller pin can sink more than 4*1.6mA of current if it wants to generate an "L" on these inputs .. Similar
From the description of your circuit, with a P-channel MOSFET connected to +supply and the 0.1Ω resistor connected to -supply (GND), it looks like you want to source current, not to sink it .. Could you post the schematic diagram of your circuit? Regards, IanP
Actually, it is easier to build a sinking current source .. Here is one example based on the PICAXE-08 microcontroller and with slight modifications it can be converted to sink currents of several Amps .. So, take a look at this example and if you have any comments please
In theory you are right: 47Ω, 147Ω .. bla .. bla .. bla .. On the other hand, these values are unrealistically low, so, don't expect these circuits to work with them .. To give you a hint, if β of contemporary BJT is easily >250 to source/sink its collector current of 1mA you need its base current to be somewhere in ?As region ..
This is not current source. It has low output resistance.
by source/sink current calibration or use current mirror to bias the output inverter stage
For designing general purpose IO, you need several steps (1) be familiar with the application since the application determines the spec ALWAYS. If you are not familiar with application, then your IO is goind to be useless finally (2) IO consists of input buffer and output buffer, separate two cases for design (3) Input buffer should always have
Generally, it is necessary to use an AMP to drive speaker or headphone, actually there is a Power AMP intergrated into chips (after Audio DACs line out). however if driving headphone load only, the output power is much smaller, it is enough if there is 30~50mA source/sink capbility, exg, opamp.
Hi Hung, nice to meet you in the same physical/structural limitation corner of application circuits! What do you think is the right business model to work in this area. I am shure if I would post any circuit solution I will do it for compensation or do it opencircuit. These circuit problems I guess are hard and have found solution which are c
Some kind of integration will always be needed. If you cannot use an RC integrator, use a DAC and a up/down counter. As your input signal is high, count upwards high frequency pulses. When the input signal is low, count downwards. The output of the counter is supplied to a DAC. A low-pass filter smoothes the DAC output. Another way could b
hi I am designing one interblock data exchange block to transfer the data between two devices. can any body send some tips and matirials for designing a source and sink to data transfer. i am doing 8 bit serial trensfer. (cmd/bank,address,data1,data2..........cycle wise).only one input and one output.
A load of a TTL can be a resistor, a capacitor, or a current source. You will refer to a electrical characteristics part of a TTL Datasheet. They specify the test conditions and limits of a TTL.
AT89c51 is having very less source current. u cannot drive led, seven segment directly u have to use drivers. source and sink current vary for controller to controller. PIC microcontrollers will sink and source 20 mA. U can directly drive the leds, lcds with PIC microcontroller
Hello all, I am now designing a differential resistor ladder that has a top current source and a bottom current source. The current that flows through the resistor ladder is 15mA. I know that for the bottom current source, I can use NPN BJT to generate the current. I also know that I could have used PNP BJT to generate the current (...)
Curl as its name imply means the vector filed move in a circular way. In other words the vector form a circular closed form. The value of the rotor is the magnitude of the rotation and the direction of the vector curl-rotor is the axis of rotation. But also means something else, a non zero curl vector means the vector field will not have a
Sorry for bad english and stupid questions =) 1. Can i use for current sink and current source in simple LVDS driver one MOS transistor? Or i shall use more difficult current source? 2. Current sink/source shall operate in saturation or triode region?
Dear all Can i use Matlab (Simulink)as data source to FPGAVirtexII pro?? and if so , what can i do ,and what is needed? ,if any materials or any other help ,it will be appreciated thanks in advance Added after 11 minutes: also i have an inquiry ,is it possible to use the Ethernet interface in spa
In the datasheet of MRF136Y, source is connected to the flange. I am so wondering how to connect the source to ground for this transistor. I guess the source may be connected to the case-sink. this case-sink may be connected to the heat sink. Is that right idea? I attach the MRF136Y (...)
Suppose we have a pipeline which will process the data in 3 cycles. Sometimes the source may have no data to send out, and sometimes the sink may not be able to receive data. Define the interface signals first, and then design the internal control logic. We must keep the throughput 1 data/cycle, and if there are any possibilities the source (...)
Hi, I am looking for a bandgap current reference circuit (0.5u n-well process) to use it as a current source for biasing circuits. My understanding is that if a reference source is temperature independant it can also be considered process(corners) independent as many process parameters change with temperature? I came across this circuit
I am not in love with that circuit. I think you will have some trouble around +/- 0 ma out. If you are going from a + current output thru zero to a - current, Q1 will turn off when its base voltage is getting around +0.6 volts, but Q2 will not start turning on until its base current is around -.6 volts. If you search the litterature, I think
What kind of gate drive circuit do you use ? for PWM inverters you must use a dedicated IC like IR2110, 2113 which can charge/discharge MOS-FET gate very fast. if you used a simple circuit like in modified sine inverter, with just one transistor and resistor for chare/discharge, this is the result. there are other options too, like fast optocoupl
I'm happy if anybody can help me. I designde a circuit ,when i get the chip ,I find my bias have problem. So I need a 10ua current source to setup the circut. How can i get the cuurent,use res,cap........
The average forward drop of a Red/Gren LED is 1.2 Volts. A Pic can source/sink ~20mA from an I/O pin. So, if you plan to drive a standard led from a 3V supply at ~20mA, your series resistor would be: (3 - 1.2) / 0.02 = 90. So a 91R or 100R would be the value to use.
I found a voltage-controlled current sink as following: For the sake of convenience, the circuit schematic in the article is copied and pasted here as Figure 1 below. I'm not sure whether I could replace the "power supply under test" with the "armature winding circuit" as shown in the modified figu