Could you please confirm that data are related to open loop output impedance? To get OPA4244 closed loop impedance is it correct to divide Zo(Aol) by the following factor: Aol/Acl?

ex: @10Hz , op amp OPA4244 (Aol=106db) configured as a voltage follower (Acl = 1) then Zo(cl) is about 727,7/199526/1=0,0037Ohms.

Thank you and best regards,

Benoît,

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THS4304-SP: THS4304-SP decoupling and implementation

May 6, 2019, 6:10 am

≫ Next: INA214-Q1: INA214-Q1 Input Resistance

≪ Previous: OPA4244: Output impedance

Part Number:THS4304-SP

Hi team, working with a customer on this device. Some questions on the implementation of the device:

Datasheet on page 12 under General applications, discusses that 0.1uF ceramic cap is critical for power supply bypass. Text implies maybe more than one is needed, if so how many?
Are you recommending a Ferrite bead between the supply and +Vs? If so, what value?
Why do you have Resistor “C5” in the picture below? Is this a Resistor, or a Cap? Figure 44, under Non-Inverting Single Supply Operation section, page 18.

Thanks in advance.

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INA214-Q1: INA214-Q1 Input Resistance

May 6, 2019, 10:41 am

≫ Next: INA2128: Regarding output circuit connection

≪ Previous: THS4304-SP: THS4304-SP decoupling and implementation

Part Number:INA214-Q1

I am using a INA214 for a somewhat unique go/no go current detection system (essentially a current comparator) and I need to know the tolerance of the 10K ohm input resistance for the INA214.
Alternatively, I could work with knowing how closely balanced that the two input resistances are to each other.

I need to place large protective resistances in series with the inputs. Yes, I know the gain will be strongly affected, but since I really just need to detect current = yes or no above some threshold, then I know I can put the series resistors there as long as I account for some variability.

The data sheet tells me what is effectively the gain tolerance but that only sets the ratio, not the literal input resistance.

Thanks

Glen

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INA2128: Regarding output circuit connection

May 6, 2019, 6:59 pm

≫ Next: LM311-N: Data Sheet for LM311H

≪ Previous: INA214-Q1: INA214-Q1 Input Resistance

Part Number:INA2128

Hi,

We used to build a system with a gain of 100x using the INA2141.

Since I want to make the gain variable this time, I am considering using the INA2128.

The design using the previous INA2141 does not understand the reason well,

but it was configured as shown in the figure. It is fine to guess the reason for this configuration,

but if you understand it, I would like to know.

Vout pin --100Ω register--+-------- Output

SENSE pin -----------------------

The output and SENSE input are connected from the Vout terminal through a 100Ω resistor.

Also, should the same configuration be desirable for the INA 2128?

Or is it better to have a configuration like the one shown in the figure?

Vout pin -------+------- 100Ω register------Output

SENSE pin ----

Connect Vout terminal and SENSE input and output through 100Ω resistance.

regards,

↧

LM311-N: Data Sheet for LM311H

May 6, 2019, 7:34 pm

≫ Next: LM7171: 20v amplification :Op-Amp negative Voltage

≪ Previous: INA2128: Regarding output circuit connection

Part Number:LM311-N

Hi,

Our customer keeps using "LM311H/NOPB" but I cannot find the data sheet on TI website, so could you please share it with me ?

Best regards,
Kato

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LM7171: 20v amplification :Op-Amp negative Voltage

May 6, 2019, 9:10 pm

≫ Next: PGA309: Schematics and Layout verification

≪ Previous: LM311-N: Data Sheet for LM311H

Part Number:LM7171

I am using IC LM7171A to generate 20v output pulse from 3.3v input (uni-polar). Below is the schematic . Do I need to connect -24v (NEG) to pin 4 of op-amp to make this work?

Thank you

Ashish.G

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PGA309: Schematics and Layout verification

May 6, 2019, 9:19 pm

≫ Next: TLV521: Negative Voltage on IN+ Pin

≪ Previous: LM7171: 20v amplification :Op-Amp negative Voltage

Part Number:PGA309

please find the attached files and kindly review and let me know the comments.(Please visit the site to view this file)

↧

TLV521: Negative Voltage on IN+ Pin

May 6, 2019, 9:41 pm

≫ Next: INA3221: Layout pattern guideline

≪ Previous: PGA309: Schematics and Layout verification

Part Number:TLV521

Dear, Sir.

My customer is considering to apply TLV521 for their system, now.

The circuit is similar as Figure34 on the datasheet(using single power supply).

They are concerning the negative voltage around -0.3V on IN+ pin will be cretaed

due to the sensor behavior.

-0.3V is the absolute maximum ratings for TLV521. Please give your advice.

1. I wonder above negative voltage would influenced to output voltage, such as

output inverting?

2. I think the putting series resistors on both IN+ & IN-to limit the input current

could be one of the solution because input offset current is quite small, 50fA.

How do you think about this idea?

3. Please give your advice if you have the better solution?

Best Regards,

H. Sakai

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INA3221: Layout pattern guideline

May 6, 2019, 9:45 pm

≫ Next: OPA551: Output changes when adding extra output channel

≪ Previous: TLV521: Negative Voltage on IN+ Pin

Part Number:INA3221

Dear E2E,

Do we have the layout pattern guideline of INA3221?

We only saw the info of IC footprint.

BR,

Jason

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OPA551: Output changes when adding extra output channel

May 6, 2019, 10:16 pm

≫ Next: OPA2196: offset voltage vs temperature

≪ Previous: INA3221: Layout pattern guideline

Part Number:OPA551

Hi, guys.

I'm using the application note

http://www.ti.com/lit/an/snoa474a/snoa474a.pdf

to create the Howland Current Pump with OPA551

I'm using two current pumps.

Case 0) When each load is resistors.

When I use 1k Ohm as a load for each current pump, the expected output is shown from the oscilloscope.

Case 1) When wrist becomes a load - I have an IRB approval

I use four H124SG Covidien electrodes. The connections are

A: Left Wrist position 2 (red) - Oscilloscope Probe 1 - Current pump 1 (U2's positive input pin)

B: Left Wrist position 1 (black) - Probe 1 aligator clip - GND

C: Right Wrist position 2 (red) - Oscilloscope Probe 2 - Current pump 2 (U4's positive input pin)

D: Right Wrist position 1 (black) - Probe 2 aligator clip - GND

This is the output.

There should be nothing on channel 2 (show 0V). Surprisingly, a similar looking output is generated to channel 2, "a mirrored output".

One surprising observation;

If I remove the connection between the second current pump and my right wrist (position 2, C),

probe 2 shows that U4's positive input shows negative voltages like -10V.

Although the human wrist is not purely resistive, this is interesting to discover to observe a negative voltage when both wrists are connected to the electrode.

- May I ask why this negative voltage is observed?

- I mentioned "mirrored output". How can I solve this in order not to make a mirrored output?

I'm going to use the current pumps alternatingly (use the left pump for 1 second -> stop that and use the other one for 1 second ->...)

or simultaneously (the left pump gives 0.1mA at 100Hz / right pump gives 0.05mA at 200Hz).

However, this mirroring phenomenon cannot make me do that. I deeply appreciate your help, please.

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OPA2196: offset voltage vs temperature

May 6, 2019, 11:23 pm

≫ Next: XTR111: REGF, REGS output voltage

≪ Previous: OPA551: Output changes when adding extra output channel

Part Number:OPA2196

Hello,

Our customer have two inquiries about OPAx196 datasheet ;

1. It does not show graph of offset voltage vs temperature. Can wee see some data looks like Figure 11 of OPAx192 datasheet ?

2. In the Figure 1(offset voltage vs common-mode voltage), please let us know the conditions for each five lines (temperatures ? or simply five different units in 25 degree C ?).

Please check above and give us your comment.

Thanks,

Hiro

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XTR111: REGF, REGS output voltage

May 7, 2019, 12:51 am

≫ Next: LM211: The voltage range of input pin of LM211 when ±15V supply

≪ Previous: OPA2196: offset voltage vs temperature

Part Number:XTR111

Hi team,

My customer is using XTR111 for 4-20mA output application.

As mentioned in the datasheet, we could add a resistive divider for the 4-20mA output.

Customer have a 0-10V signal input, so they would need a 10V Reference voltage for this.

Could they just use the REGF and REGS to generate the 10V for this reference votalge?

Would this have some concerns for the long term?

Thanks.

↧

LM211: The voltage range of input pin of LM211 when ±15V supply

May 7, 2019, 12:57 am

≫ Next: LF353: LF353 use problem

≪ Previous: XTR111: REGF, REGS output voltage

Part Number:LM211

LM211 differential comparator is used in our application because of its fast response time(165ns).

Our voltage comparison circuit is shown in the following figure. the circuit consists of three parts : resistance divider circuit, diode clamp circuit and voltage comparator circuit. The voltage of diode clamp circuit is 15V, the positive and negative supply of LM211 is 15V & -15V and the reference voltage is 8V.

In our application, the voltage to be measured(V1) is always very high, and the voltage of pin IN+ of LM211 is up to 15.7V considering the forward voltage drop of diode(0.7V) when the diode D1 is conducting.

According to the datasheet of LM211, the input voltage is not allowed to excess 15V.

Here is my question:

1.Is there any damage when the voltage of pin IN+ of LM211 reach 15.7V?

2.Is there any incorrect of logical output in our application?

3.What is the voltage range of pin IN+ when the positive and negative supply of LM211 is 15V & -15V and the reference voltage is 8V?

4.The input voltage(VIN+) is higher than positive supply of LM211(Vcc+) when the voltage of diode clamp circuit and positive supply is same. Could you give me some recommendations on circuit design or chip selection in our application? we need fast response time which is similar to LM211.

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LF353: LF353 use problem

May 7, 2019, 1:57 am

≫ Next: LM2903: Input filter recommend for LM2903

≪ Previous: LM211: The voltage range of input pin of LM211 when ±15V supply

Part Number:LF353

Hello：

I am using LF353. When I ordered a new batch of LF353, the output deviation of out(7pin) was very large during the test.

Want to know, what reason is caused.

The verification method is as follows:

1.Cross validation： verification results, problems follow IC

2. The resistance and capacitance of LF353 differential output series were removed, but the problem remained unchanged.

3.Failure IC is tested under the same conditions as normal IC.

IF353	Differential input voltage(mV)(5pin& 6pin)	7pin(mV)	1pin(mV)
Test normal IF353	100.1	93.1	93.3
Test failure IF353	100.3	110.2	110.9

Best Regards

Leon

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广东省深圳市南山区高新中三道9号环球数码大厦12楼

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↧

LM2903: Input filter recommend for LM2903

May 7, 2019, 2:04 am

≫ Next: INA300: SCH Review: Vpwr = 5V; Itrip = 10mA; I_Max = 100mA

≪ Previous: LF353: LF353 use problem

Part Number:LM2903

Hi team,

previously you have helped to reviewed the schematic of the LM2903.

And it seems the schematic is OK. As below:

Now because there is some noise in the input signal, customer want to add a 2.2nF cap in the input pin to form a filter.

Can you help to comment if it's ok for LM2903, if not, what's your recommendation?

Lacey

Thanks a lot!

↧

INA300: SCH Review: Vpwr = 5V; Itrip = 10mA; I_Max = 100mA

May 7, 2019, 6:08 am

≫ Next: TINA/Spice/OPA551: use the amp with single supply

≪ Previous: LM2903: Input filter recommend for LM2903

Part Number:INA300

Hi Sir,

Could you help to check below SCH? Please help to provide your suggestion, if there is any concern. Thanks.

Vpwr = 5V

Itrip = 10mA

I_Max = 100mA

↧

TINA/Spice/OPA551: use the amp with single supply

May 7, 2019, 6:31 am

≫ Next: INA260: can A1/A0 pin connect 10k ohm to GND?

≪ Previous: INA300: SCH Review: Vpwr = 5V; Itrip = 10mA; I_Max = 100mA

Part Number:OPA551

Tool/software:TINA-TI or Spice Models

Hi,

I want to use the OPA551 with SINGLE supply.

1. the amp circuit works when the amp is powered with +-30V;

2. there is something wrong when the amp is power with single supply.

here is the TINA simulation file.

(Please visit the site to view this file)

1. Can the opa551 be used with single supply? Is there something wrong with my simulation?

2. Can you please recommend an amp with at least 50V output voltage and 200mA current?

Looking forward to your reply.

Best regards,

↧

INA260: can A1/A0 pin connect 10k ohm to GND?

May 7, 2019, 8:23 am

≫ Next: USB2ANY: USB2ANY: use USB2ANY.dll in own software GUI project

≪ Previous: TINA/Spice/OPA551: use the amp with single supply

Part Number:INA260

Hi team,

In INA260, can A1/A0 pin connect 10k ohm to ground? The address should still be seen as "1000000" (A1=GND/A0=GND)?

Or you suggest change these resistors to 0 ohm?

Just would like to make sure everything on customer schematic is fine.

Thanks.

↧

USB2ANY: USB2ANY: use USB2ANY.dll in own software GUI project

May 7, 2019, 9:36 am

≫ Next: LMP8481: LMP8481 temperature drift on 1 in a 100

≪ Previous: INA260: can A1/A0 pin connect 10k ohm to GND?

Part Number:USB2ANY

Hello Team,

I have seen the following discussion on USB2ANY which my customer ask me today:

e2e.ti.com/.../2592120

I download the software, but do not find the following USB2ANY SDK part information under the folder where I should find a folder with some sample code (looks like header and sources files for C/C++) of using I2C, a API reference guide, some release notes referring to the DLL, and plenty of other seemingly helpful PDFs.:

: C:\Program Files (x86)\TI USB2ANY SDK

Since my customer want's to use the USB2ANY tool also (in conjuction with the Analog Launch Pad) can you let me know where we can find the described information in the thread shown above?

Thanks

Albert

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