This thread has been locked.
If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.
LMH32401: LMH32401 APD bias voltage
Part Number: LMH32401
How could I connect LMH32401 with a negative voltage and APD. Is the below circuit OK? The (Out+)- (Out-) is in accordance with the APD current, right?
And could you please give me some guidance(with picture) if my connection is wrong?
Boost DC/DC Solution
Below is the photo-diode configuration as shown in the datasheet:
You should not connect ground to the input pin. The LMH32401 will provide a positive bias of around 2.5V.
We are glad that we were able to resolve this issue, and will now proceed to close this thread.
If you have further questions related to this thread, you may click "Ask a related question" below. The newly created question will be automatically linked to this question.
In reply to Hasan Babiker31:
What about the below connection , is it OK? What is the right connection if the below circuit is still wrong? Could you please show me by picture?
In reply to Helen chen:
Yes this should work. Not sure of the photodiode you are using here, but the 10k resistor may limit the input current of your circuit.
Thank you for the update Hasan.
One more question, what kind of APD you used in your test? Could you please share the APD part number(around -60V - -90V rating ) and the resistor value with us? We want to promote our negative boost solution to our customer. But we lack of the APD application knowledge.
To clarify, I think it'd be better to not include the 10k resistor so you can get the full performance of the photodiode. Outside of the promoting the boosting feature are there any requirements for this photodiode? Are you looking for a fiber connected or open type photodiode?
The information we got is -60V/10mA or -90V/2mA photo diode.
I have no idea of fiber connected or open type photo diode, any difference?
The difference is how you plan on providing light to the photodiode. For an open-type, you can just shine a light on the device vs. with a fiber-connected photodiode you would typically connect to a laser diode through a fiber connector.
You can see the difference here (unmounted vs. pigtailed).
Thanks for the information, its interesting.
I want to use an open-type photodiode in my application. Do you have some part number to recommend to us? :) It will be helpful to us.
Options will vary based on specifications of your light source. Hamamatsu and first sensor should have a lot of options that you can take a look at.
All content and materials on this site are provided "as is". TI and its respective suppliers and providers of content make no representations about the suitability of these materials for any purpose and disclaim all warranties and conditions with regard to these materials, including but not limited to all implied warranties and conditions of merchantability, fitness for a particular purpose, title and non-infringement of any third party intellectual property right. No license, either express or implied, by estoppel or otherwise, is granted by TI. Use of the information on this site may require a license from a third party, or a license from TI.
TI is a global semiconductor design and manufacturing company. Innovate with 100,000+ analog ICs andembedded processors, along with software, tools and the industry’s largest sales/support staff.