Hi, I am wondering of calculating input impedance of OPAMP.
I kind of understand why input impedance is R1 in above circuit.
But I think current from source also flows to feedback loop.
Then, why we do not consider Rf in calculating input impedance?
Thanks,
Yunsik
Tool/software: WEBENCH® Design Tools
Anika,
About tlv320aic23evm2 ,in slave mode ,input signal from linein,don't anything in lineout. Have you solved it?
If you have solved it, please tell me ,thanks！
Best regards!
Hai.
Part Number: TPS2480
Hi
There are some layout guide in datasheet, I have two questions:
1. Gate amplifier have hign bandwidth means can accept more noise, so need the trace short, is this right? or some other consideration.
2. The PROG TIMER EN pin have high input impedances, why these high impedences pin especially need the leads short, what's the consideration of short lead and high input impedances.
Thank you.
Part Number: DS90C185
Hi.
Please tell me the meanings of this notation "DS90C185(Transmitter)", like Fig 5 "DS90C185 (Transmitter) Input Clock Transition Time".
I think "DS90C185 (Transmitter)" and "DS90C185 (Serializer)" mean the same things. Is it right?
I'm confused it is written "transmitter" though it is written "Input".
I want to confirm "DS90C185 (Transmitter) Input Clock Transition Time" means "LVCMOS Input Transition Times" like DS90C187 Fig 5.
Best Regards.
Ryu
Part Number: AM3358
Hi. there
I want to create a configuration like this:
Except for the data that comes to me, I want to send it to another port as it is.
Q1. Can I configure with the AM3358 Starter Kit?
Q2. Should I use CPSW mode or Dual Mac mode?
Q3. Please let me know if there is anything that would help me.
Regards,
Simon
Part Number: TAS5805M
Hi,
customer found that on their board, when the volum lower than -60dB, we can hear the pop sound. With the volum goes up, the pop sound will gradually disapper. the noise not amplified with the volum increase.
1. Check the output PWM on the customer board, the waveform as below, didn't find the any noise and jitter at -60dB.
2. With the different audio source, can heard the pop on the customer board.
3. Use the customer 's .cfg file on the TAS5805M EVM,can't heard the pop.
I found that the different between customer board and EVM is that, in the customer board, there is no PWM output when no sound play while in the EVM there has the 50% duty-cycle PWM output always. Does this affact pop?
thank you
Part Number: SN75DP159
Hello expert,
My customer got a FA case and the issue is their NB cannot show the screen to HDMI display. After A-B-A testing, we know that issue does follow IC. And impedance is shown as below table. It seems like there are OUT and VDD impedance different. May I know if this IC is still good or can we send to FA step? Thanks a lot!
| top side marking | 75DP159 | 75DP159 | |
| TI 74I | TI 88I | ||
| CHFJ G4 | A4YD G4 | ||
| good sample impedance | FA sample impedance | ||
| (PIN NO.) | |||
| 1 | SWAP/POL | 70k | 68k |
| 2 | IN_D2p | 68k | 67k |
| 3 | IN_D2n | 68k | 67k |
| 4 | HPD_SRC | 47k | 47k |
| 5 | IN_D1p | 68k | 67k |
| 6 | IN_D1n | 68k | 67k |
| 7 | GND | 0.7ohm | 0.8ohm |
| 8 | IN_D0p | 68k | 67k |
| 9 | IN_D0n | 68k | 67k |
| 10 | I2C_EN/PIN | 90k | 90k |
| 11 | IN_CLKp | 68k | 67k |
| 12 | IN_CLKn | 68k | 67k |
| 13 | VCC | 31k | 31k |
| 14 | VDD | 1.49k | 2.2k |
| 15 | SCL_CTL | 727k | 731k |
| 16 | SDA_CTL | 730k | 725k |
| 17 | NC | 90k | 90k |
| 18 | CEC_EN | 47k | 46k |
| 19 | GND | 0.3ohm | 0.7ohm |
| 20 | PRE_SEL | 70k | 67k |
| 21 | EQ_SEL/A0 | 70k | 68k |
| 22 | Vsadj | 25k | 24k |
| 23 | VDD | 2.6k | 2.7k |
| 24 | VDD | 2.2k | OL |
| 25 | OUT_CLKn | 75k | 74k |
| 26 | OUT_CLKp | 75k | 74k |
| 27 | #HDMI_SEL/A1 | 90k | 90k |
| 28 | OUT_D0n | 75k | 74k |
| 29 | OUT_D0p | 75k | 74k |
| 30 | GND | 0.3ohm | 0.7ohm |
| 31 | OUT_D1n | 75k | 78k |
| 32 | OUT_D1p | 75k | 78k |
| 33 | HPD_SNK | 191k | 185k |
| 34 | OUT_D2n | 75k | 48k |
| 35 | OUT_D2p | 75k | 48k |
| 36 | TX_TERM_CTTL | 70k | 68k |
| 37 | VDD | 2.2k | 2.4k |
| 38 | SCL_SNK | 751k | 760k |
| 39 | SDA_SNK | 741k | 753k |
| 40 | SLEW_CTL | 68k | 67.5k |
| 41 | GND | 0.3ohm | 0.7ohm |
| 42 | OE | 95k | 94k |
| 43 | VCC | 31k | 31k |
| 44 | AUX_SRCn | 15k | 15k |
| 45 | AUX_SRCp | 16k | 15k |
| 46 | SCL_SRC | 768k | 753k |
| 47 | SDA_SRC | 747k | 735k |
| 48 | VDD | 1.49k | 2.2k |
| Thermal Pad | 0.3ohm | 0.3ohm | |
Best regards,
Ann Lien
Part Number: TAS5756M
HI
Is there a document for TAS5756M register manual ?
Part Number: TPS65987D
Hi Team,
I got a problem when use TPS65987D on a new project, the problem is PD can't work, I measured the SPI wafeworm when power on, it likely loaded, but the GPIO0,1,2,3 and CC1/CC2 status is abnormal, GPIO status is always high impedance, and CC1/CC2 is always low, and attachment is schematic and configuration file, please help to check which cause the problem.
SPI SDO and CLK waveform when power on:
(Please visit the site to view this file)(Please visit the site to view this file)
Part Number: MSP430F5418A
Hi team,
My customer speculated that during the test flash write, the flash at the boot loader address may be written out.
Is there any way to re-write the boot code of MSP430F5418A?
Thanks and best regards,
Jamie
Part Number: UCC256402
Hi expert,
My customer need to know how to calculate the highest switching frequency and Ton at startup. Could you offer any help on this?
Thanks
Sheldon
Hi team,
My customer wants to translate YUV/RGB to differential signals or USB signals to improve the EMI issue.
Could you kindly provide a solution?
Thanks and best regards,
Jamie
Part Number: ADS1278-EP
for ADS1278-EP ADC, should SPI interface clock is connected oscillator (or) SPI master interface clock (or) from any other timers (which generates sufficient clocks)?
and also need to know, how master SPI interface i.e., MISO, MOSI, SCLK and CS# is connected to this ADC?
Part Number: CC1310
Tool/software: Code Composer Studio
How does sensor controller configure adc and timer in RTOS?Adc acquisition and timing function for low power operation
Part Number: TMS320F28335
Hello All,
I am working with TM320F28335 microcontroller. I am planning to use eCAP module to measure duty cycle, frequency of an external signal of 1kHz.
As i went through the datasheet, i understood that i need to use delta mode function, with the counter TSCTR resetting every rising edge and falling edge.
Then reading out the CAP1-4 registers gives me duty cycle and frequency values.
I have a doubt here with respect to clock input to the TSCTR, it is 150MHz in my application and using this clock, the TSCTR counter would have overflown 'n' number of times before it is reset either at falling or rising edge(for 1kHz signal). So the measurement of dutycyle and frequency will be wrong.
Is there any configuration that takes care of this problem?
I cannot change SYSCLK as it is module clock for other modules.
Please let me know how this can be worked out for 1kHz signals.
Thank you!!
Part Number: TLV320ADC3140
Hi Experts,
We want to check with you if we can achieve 4 analog MICs plus 1 digital MIC for TLV320ADC3140 via TDM mode, it looks like we can do this from the device block diagram, but want to double confirm with you. Thanks.
Part Number: AM6548
Hi TI,
The command 'rproc init' failed in u-boot and the CPU number is PSN6548ACDXBS1 . The log is as follows:
=> rproc init
ti-sci processor set_config failed: -19
rproc configure failed -19
Few Remote Processors failed to be initialized
But executing the same command in u-boot successfully and the CPU number is XAM6548ACDXEAFS1
Part Number: FDC2214EVM
Hi,
I am looking to build a differential measurement system using two co-planar capacitance sensors for liquid dielectric constant measurement, with active in-phase shielding for both the sensors. My measurements have to be done at fixed excitation frequencies 1 MHz and 5 MHz/10 MHz(all separately, not in a single measurement). The base capacitance of my sensors (both the co-planar capacitors) is close to 0.65 pF.
I have the following questions
1. How to build an active shield for both of my sensors. I read in one of forums , one way is to use an OP-AMP with a unity gain but I am not sure which channel should be using for driving it and will the signal be in phase with the sensor.s. Meaning, I would be connecting my two sensors to say Channel0 - IN0A & IN0B with and ground the other plates. Will a signal from, say IN1A and IN1B through an op-amp, say OPA322, act as shield inputs for my sensors connected to IN0A and IN0B respectively ?
2. How do I change the excitation frequency for the device to a precise value ?
3. My sensor capacitance value is way off close to 20 pF in a single ended measurement (the LC tanke values are 18 u and 33pF) when I measure it using the EVM. Am I missing something blatant here ? The oscillator frequency I am using is 40 MHz
So sorry if any my questions are too naive, I am a biologist with limited electrical engineering knowledge!
Any help would be greatly appreciated!
Regards
Praveen
Part Number: LM5170
Tool/software: WEBENCH® Design Tools
Hi,
I have variable input voltage for example from 18V to 30V (Pb batteries or alternator), I would like to use LM5170 like a boost converter.
How will the converter behave when the input voltage is higher than the output?
Thank you.
Tool/software: Code Composer Studio
Hi,
I followed the guide provided by TI for uboot compilation in CCS
I have installed CCS V9
Facing following issue upon compilation
CC lib/asm-offsets.s
cc1: error: bad value (‘armv5’) for ‘-march=’ switch
cc1: note: valid arguments to ‘-march=’ switch are: nocona core2 nehalem corei7 westmere sandybridge corei7-avx ivybridge core-avx-i haswell core-avx2 broadwell skylake skylake-avx512 bonnell atom silvermont slm knl x86-64 eden-x2 nano nano-1000 nano-2000 nano-3000 nano-x2 eden-x4 nano-x4 k8 k8-sse3 opteron opteron-sse3 athlon64 athlon64-sse3 athlon-fx amdfam10 barcelona bdver1 bdver2 bdver3 bdver4 znver1 btver1 btver2
Kbuild:43: recipe for target 'lib/asm-offsets.s' failed
Makefile:1276: recipe for target 'prepare0' failed
Note:
I have exported the environmental variables too,like ARCH ,CC,CROSS_COMPILER,etc
Can you please help me out for u-boot compilation?am I missing out something ?can I know is it possible to compile u-boot in CCS v9?