LMH6526: Question Regarding Stability of LMH6526

Hi ZQ,

Can you provide the circuit that you are using, especially the amplifier's load? The stability is not technically related to the pulse width, and we can be compensate based on your circuit. You can only get 600mA from summing all the channels together, so yes the 40mA example is not demonstrating this.

Best regards,

Sean

Hi Sean,

Thanks for your reply. I don't know the load of SOA since there's nothing at its website. But I'm contacting the manufacturer to request the information. Meanwhile, I tried to connect 5 Ohm as load, used 300mA output channel, and set pulse width as 20ns. The pulse is around 1.5V which is correct for 300mA. However, the overshot approximate 2.8V, and some ripples at pulse certainly decrease the laser's performance. Could you give me any suggestion on dealing with this unexpected pulse shape?

 

Best,

ZQ

Something is definitely wrong. Can you please show us your circuit. What are your Rf and Ra values? What are you using to drive your input current signal?

Please check the circuit below. I only used channel 2 to send a differential pulse signal in and turned off internal oscillator by connecting to ground.