Other Parts Discussed in Thread: INA170
Hi there
I'm following up on a test related to the INA139 and simulations in TI-TINA.
The current that I want to take to sample is from -2.5 A to +2.5 A, and the frequency is range from 100K Hz to 1M Hz. The current waveform is a triangular wave.
The intention is to use two INA139's in a bipolar configuration to measure the bidirectional current , the sense resistor is 10 milliohm. So the VSENSE=VIN+ - VIN-=-25mV-+25mV. The V+ is 5V,and Rload is 1K, so
the Gain is 1.
The device(INA139) named A is to be used detecting positive voltage of the VSENSE, I found that :the frequency of the current is 100KHz, when the VSENSE is negative ,the VOUT of A is zero, but when the
VSENSE become positive ,the VOUT remained zero until 1.2 us later, then it began to grow. As the frequency increases, the phenomenon becomes more serious. What is the reason?
In the datasheet, FREQUENCY RESPONSE
Settling Time (0.1%) | 5-V Step, ROUT = 10 kΩ | 2.5 | 2.5 | µs | |||||
5-V Step, ROUT = 20 kΩ | 5 | 5 | µs |
What does this parameter mean?
Now I want to use the INA 170. Will this device have the above phenomenon and whether the bandwidth meets my conditions of use?
Thanks
LIN