LMH2121: Envelope Detector Referance Design?

Pete Sampson

Part Number: LMH2121

Tool/software:

Are there any referance design or apps notes for envelope detectors?

I'm looking to make an envelope detector for a 500kHz signal. Ideally it would be a full wave envelope detector but a half wave would be better than nothing. The LMH2121 is for 100M to 3GHZ and much faster and power hungry than I need. The diode detector it referances in the datasheet as an example won't pass small signals until they get over the forward drop of the diode so that won't work.

over 1 year ago

0 Hruday Kumar Mudireddy over 1 year ago

TI__Expert 4830 points

Hi Pete,

Is the modulation bandwidth 500KHz? Can you help me understand your signal type?

Regards,

Hruday

0 Pete Sampson over 1 year ago in reply to Hruday Kumar Mudireddy

Intellectual 470 points

Thanks Hruday, happy to provide more information. The signal being received is centered at 500khz. The pulse length is 10-20uS so bandwidth is +-50kHz (100kHz max). The signal will be either a PWM or a sine wave but either way I want to track the amplitude vs. time, rather than needing to demodulate or process a 500 kHz sine wave with a micro.Since this is a battery operate system low power is key.

The signal is the return signal for a sonar system but I don’t want this to be moved to the sonar section where the chips already have integrated envelope detectors. I want to build my own external envelope detector using TI parts.

0 Pete Sampson over 1 year ago in reply to Pete Sampson

Intellectual 470 points

Bumping this up again. If I can provide additional info please let me know.

+1 Hruday Kumar Mudireddy over 1 year ago in reply to Pete Sampson

TI__Expert 4830 points

Hi Pete,

Apologies for the delayed response. I see you want to detect 500kHz signal with detector response time << 10uS. Currently TI do not offer any power detector with min frequency < 50MHz. unfortunately, I did not find any suitable parts from TI to implement this discretely.

Regards,

Hruday

Amplifiers

Amplifiers forum

LMH2121: Envelope Detector Referance Design?