/etc... Analog

Forum Post: LMP91200 pH sensor - Analog only?

David Wipf — Wed, 22 May 2013 19:32:00 GMT

I have a question about the LMP91200 sensor chip.

At the moment, I don't need to use the SPI programming options and I would like to use it just as an analog circuit element.

My question is, will the chip power up and operate with the default settings (as on page 19 of the data sheet) with no activity on the SPI interface.

Also, what would you recommend for the unused SDI pins?

Should I pull them either low or high to minimize power consumption.

Forum Post: RE: MSC (MicroSystem Controller) family

cruceru malin — Tue, 21 May 2013 01:40:00 GMT

Hi!

My name is Cruceru Malin and i am a physiscs student in bucharest,Romania.

I got hold of and msc1214y4pagt precision adc/dac and i want to use it in my graduation thesis about data aquisition but i haven't had any luck in finding any referece circuit,developer software,ide and so on.

Can you please help me?

Forum Post: RE: Communication with SM-USB-DIG

Mamatha Reddy — Mon, 20 May 2013 09:49:00 GMT

Hi Lisa,

Please could you share that C++ program, I need to port that code onto Linux. Have you tried it on Linux ?

Regards,

Mamatha

Forum Post: RE: LED matrix 3x3 to MCU

Alexander Zhigalov — Tue, 14 May 2013 14:01:00 GMT

Dear Ronald,

Thank you for your reply. I will try to use transistors as you suggested. There is also an alternative scheme (but without ULN2003): http://www.mikrocontroller.net/attachment/123772/LED_Matrix_8x5.png

Alexander

Forum Post: RE: AFE4300 different result with AC rectification and I/Q Modulation

Praveen Aroul — Sun, 12 May 2013 16:56:00 GMT

Hello Juan,

The current signal that is injected and the voltage signal that is measured are AC. Also the transmit and receive circuits are locally biased.

So theoretically it should work. But we have not tested with capacitive electrodes.

Can you tell me more about the electrodes from the commercial scales? Are those ITO electrodes?

Forum Post: RE: Push-pull output stage configuration, common emitter or common collector

Ron Michallick — Fri, 03 May 2013 16:13:00 GMT

Jiri,

Each transistor is a common collector amplifier. The input is on the base and the output is on the emitter, therefore the collector is "common" to both.

This common collector (emitter output) setup gives a low output impedance and the base currents are used by the load (not wasted). No phase splitter is needed.
As drawn, crossover distortion is a potential problem. The output is also not rail to rail. This circuit is used for old designs like LM324.

However, almost all modern design have common emitter (collector outputs) that will give rail to rail output performance.
Many times the bi-polar transistors are replaced with MOSFETs.

Forum Post: MSL (moisture sensitivity rating) for PC87427

Gavin King — Thu, 02 May 2013 11:01:00 GMT

Hello,

I am looking for the MSL rating (mositure sensitivity rating) for this device, please:

Winbond PC87427.

Kind regards,

Gavin.

Forum Post: RE: ts3a225e jack selection

Mauro Cleris — Mon, 29 Apr 2013 14:39:00 GMT

Hello,

you are right, the 2SJ3018-001311 enters in the 'poor jack usage' picture (Fig. 24 of the TS3A225E Datasheet), the reason is that the RING1 is detected (not the TIP).

Nevertheless, refering to 2SJ3018-001311, when you plug a connector in the jack, #4 contact shorts with #5.

So, simply connect on your board #4 to AVDD and #5 to DET_TRIGGER with the suggested 100kOhm PD resistor.

Mauro Cleris

Forum Post: LMP 91051

Bruce Cardoza — Thu, 25 Apr 2013 00:48:00 GMT

I am evaluating the LMP91051 to replace our discrete IR sensor front end cct interfacing to a Heimann HTS E21 xxx thermopile detector.

Most thermopiles use the case as circuit common. in our application, the thermopile case is in contact with an aluminum sample chamber which is grounded to reduce noise. It is also externally accessible.

The LMP 91051 requires the CMOUT be connected to the thermopile common and so [in our application] making the aluminum case "live" which we will need to isolate to avoid shorting it to gnd.

Is there any way around using the CMOUT? I would like to maintain the sample chamber gnd connection.

Forum Post: RE: LM4050 warmup defect

Christoph Goeltner — Wed, 24 Apr 2013 23:25:00 GMT

Hi Claude,

sorry for getting back to you so late on your warm-up issue.

Do you still have this question open?

Greetings

Chris Goeltner

Forum Post: RE: Help: Two current transmitter XTR115 in the same board

Gaston_Melo_Arg — Mon, 15 Apr 2013 12:45:00 GMT

Scott,

I want to do something similar to Rodrigo, instead of using a DAC i'm using a msp430 to generate two PWM's that will be connected to two XTR117. I was thinking to use two ISO,one for each XTR117 (to avoid interaction between Iret of each XTR117), is this possible? Is there an IC like the XTR117 but instead of have one 4-20 output has two output 4-20?

Best Regards

Gastón

Forum Post: RE: Load Capacitance of Analog Differential Signals

Bruce Trump — Sun, 14 Apr 2013 12:47:00 GMT

Sachin,

It purely a guess, but this probably best modeled as 5pF on each output to ground. This is based on what might be creating the capacitance. If you want to provide more information on the sensor such as a link to its data sheet, I may be able to determine more from the context of the information.

Regards, Bruce.

Forum Post: RE: AC Current Sensing

greenja — Tue, 09 Apr 2013 18:04:00 GMT

That is correct. The only problem is you would not know which of the solenoids were shorted without physically going to inspect it. If this is for a sequential operation, then it wouldn't mater.

Thanks,

Forum Post: SM74611

WILLIE MCCAIN — Sat, 06 Apr 2013 01:22:00 GMT

CAN THIS PART BE USED ACROSS LEAD ACID CELLS

TO BALANCE THEM IN SERIES LETS SAY USING 12 VOLT CELLS 12 IN SERIES

Forum Post: RE: analog basic

manojk peradka — Sat, 30 Mar 2013 03:34:00 GMT

thanks a lot sir..............

Forum Post: Connection to LMP91200

Rastislav Birka — Sun, 24 Mar 2013 20:37:00 GMT

Hi,

i started create aquarium controller based on arduino mega 2560 R3 where one part is pH meter with LMP91200

i have pH probe with BNC connector, not Triax like is in LMP91200 document

is connection between BNC and LMP91200 good?
has a sense connection to guard pins in that case?

p.s. sorry for my english ;-)

Forum Post: LMP91051

Flitcraft — Tue, 19 Mar 2013 13:53:00 GMT

The LMP91051 is specified as a thermopile AFE. Can it also be used with pyroelectric detectors?

Forum Post: IR detector that can serve double duty as an ambient light sensor

Ken Stewart-Smith — Mon, 04 Mar 2013 15:42:00 GMT

My application require both an ambient light sensor and an IR detector. For the ambient light portion, I can simply read the output into an ADC input. For the IR detection, I can run the same signal through a comparator. The sensor will be used as an ambient light sensor for most of the time and occasionally as an IR input. Can you recommend any TI parts that can do both so that I only need one sensor?

Thanks

Forum Post: RE: Stray voltage/current on noninverting input of OPA1662

Alexandru Gagniuc — Tue, 26 Feb 2013 23:04:00 GMT

Bruce,

Thank you very much for your input. I never imagined going from the textbook to an actual circuit would be so filled with exciting challenges. I will try the OPA2171 and the TLC072.

Forum Post: TS3A24159

Alessandro Chianetta — Tue, 26 Feb 2013 17:18:00 GMT

I'm using TS3A24159 in the following configuration:

Where:

- R13 is open

- PD4 and PB7 are control inputs (Hi or Low)

- VDD: power supply

- I want VXX = VDD only when PD4 is HI

- I want VIN = VBAT only when PB7 is Hi

Is it correct to use:

- COM1 and COM2 as switch ipunts?

- NO1 and NO2 as switch output?

- leaving NC1 and NC2 open (better resistor connecte to GND)?

In my configuration I measure 0.8V on NO1 and N02 when IN1=0 and IN2=0

best regards.