2 nSec Pulse Amplification

[adnan012]

hi

I want to amplify a short pulse of 2 nSec (Vp 200mV, Rise time 500pS). I have the following devices

BF998
BFR96
BF135
MSA-0886
PD85004
CGH40006P

Can i use any of the above device and which type of amplifier i used to amplify short pulses?

regards

 

[FvM]

Some can be probably used. The specification is however incomplete:

- DC capable amplifier yes/no
- gain respectively output level
- input/output impedance 50 ohms?

I would prefer some kind of MMIC amplifier module, e.g. form Mini-Circuits.

 

[cariban]

As a rule of thumb, BW = 0.35/Rt, where Rt is the rising time. So for your case, you need about 700MHz bandwidth to keep a good shape of the pulse.

 

[FvM]

As a rule of thumb, BW = 0.35/Rt, where Rt is the rising time. So for your case, you need about 700MHz bandwidth to keep a good shape of the pulse.

The estimation is valid for first order low-pass respectively system with dominant pole. To keep 500 ps rise time of a band limited input signal, the bandwidth must be higher than 700 MHz. Quadratic summation of risetimes can be a first estimation.

 

[cariban]

The estimation is valid for first order low-pass respectively system with dominant pole. To keep 500 ps rise time of a band limited input signal, the bandwidth must be higher than 700 MHz. Quadratic summation of risetimes can be a first estimation.

Yes, this estimation is only enough to keep more or less the same integrity for digital signals. Depending on the shape of rising/falling edge, more sidelobes should be included to get less distortion.

 

[adnan012]

Thanks for reply

More spes are

DC capable amplifier ---------------------------no
gain respectively output level-------------------not required
input/output impedance 50 ohms -----------------yes

So any mmic with 4 or 6 GHz bandwidth will work well.

 

[D.A.(Tony)Stewart]

"I want to amplify a short pulse "

What gain?

 

[adnan012]

Thanks for reply.

I need 10-12 db gain.

 

[cariban]

The input power is about 0dBm, with 10-12dB gain, the output power will be 10-12dBm. So I fully agree with FvM, MMIC amplifiers from Mini-Circuits are good candidates. They are much easier to use.

 

[D.A.(Tony)Stewart]

You haven't said anything about the application because similar has been done before with Logic in many different ways. ECL,PECL, CML,SAS,SATA,LVDS etc .

Do you care about jitter, equalization for losses on FR4, EMI, differential 50 Ohms? Impedance tolerance? Prop Delay? Return Loss? 25mV De-noise hysteresis? DC bias, ESD protection? Make,? buy? 1 or many? With Connectors? Evaluation Board? For Radar? for GPR? for Laser? etc etc?

LVDS Eval SN65CML100 can be configured to drive a dual 50-Ω load. In this configuration one 50-Ω resistor (tied to the termination voltage VTT) is placed near the output of the SN65CML100 and a second 50-Ω resistor (also tied toVTT) is placed near the end of the transmission line.
2 GBPS 1.4Vpp x2

 

[adnan012]

Thanks for reply.

Its for GPR application.

Regards