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Products => Test Equipment => Topic started by: BillWojo on September 16, 2014, 01:43:35 am

Title: AD584LH 4 output voltage reference not working
Post by: BillWojo on September 16, 2014, 01:43:35 am
Got home tonight to find my Chinese voltage reference in the mailbox. Fired up my new to me HP 3456A and hooked it up. Darn thing would not come on, no leds, no voltage! Maybe it's a dead battery but I don't have a 5VDC wallwart to plug into it. Wish they would have put a USB connector on it instead. Just sent a letter off to the seller in China, let's see his response. I sure hope he doesn't expect me to send this back, probably cost more to ship it than I paid for it. After the reviews I read on this thing , I sure didn't expect this. Oh well, I'll keep you posted on how it's handled.

BillWojo
Title: Re: AD584LH 4 output voltage reference not working
Post by: BillWojo on September 16, 2014, 02:05:49 am
Just opened it up, battery is sitting just below 3VDC. Looking all over for a wallwart, Can't find a darn 5VDC unit.

BillWojo
Title: Re: AD584LH 4 output voltage reference not working
Post by: radhaz on September 16, 2014, 02:56:41 am
Id you've got a bench supply, these are handy:
http://www.ebay.com/itm/AC-8X-Power-Plug-Connector-Adapter-w-Cable-for-Laptop-DC-Power-Supply-Multi-use-/390924568968?pt=LH_DefaultDomain_0&hash=item5b04eb8988 (http://www.ebay.com/itm/AC-8X-Power-Plug-Connector-Adapter-w-Cable-for-Laptop-DC-Power-Supply-Multi-use-/390924568968?pt=LH_DefaultDomain_0&hash=item5b04eb8988)
Title: Re: AD584LH 4 output voltage reference not working
Post by: BillWojo on September 16, 2014, 04:03:06 am
The seller just got back to me. Said go buy a power supply. I just ordered one from Ebay, should be here in a few days. Of course I'll find something by than. I wish they would either include a ps or use a USB port.
radhaz, that looks handy and yes I have a few bench supplys.
Thanks

BillWojo
Title: Re: AD584LH 4 output voltage reference not working
Post by: BillWojo on September 16, 2014, 12:57:08 pm
Thanks gazelle, I'll check mine for the battery puncture problem.
Is there a way to filter those spikes out? Probably not easy or it would have been done I guess.
Thanks again

BillWojo
Title: Re: AD584LH 4 output voltage reference not working
Post by: Andreas on September 16, 2014, 08:48:46 pm
Hello,

is there really a AD584LH populated?
Analog Devices does only produce JH and KH grades according to the latest data sheet.

With best regards

Andreas
Title: Re: AD584LH 4 output voltage reference not working
Post by: Andreas on September 16, 2014, 09:07:02 pm
Quote from: gazelle on September 16, 2014, 08:53:46 pm
Hello Andreas,
                      I checked mine using a magnifier - AD584LH is embossed in the metal CAN package.

cheers,
gazelle

Thanks,

The latest datasheet change was 05/2012 so the datecode on the LH device should be before this date.

With best regards

Andreas
Title: Re: AD584LH 4 output voltage reference not working
Post by: Co6aka on September 17, 2014, 02:54:05 am
Quote from: Andreas on September 16, 2014, 08:48:46 pm
Analog Devices does only produce JH and KH grades...

If you search for older datasheets you'll find it referenced; the "LH" is indeed a genuine part.

There's also a problem with these references in that some had bad MOSFETs in the Vselect circuit. One or more of the reference voltages will be low and unstable. Just replace the respective MOSFET and all is well.
Title: Re: AD584LH 4 output voltage reference not working
Post by: BillWojo on September 19, 2014, 09:58:47 pm
Well my charger came in today and I hooked it up. Seems that the battery must have allready been punctured as it swelled up and leaked onto the circuit board. I wondered why when it was on the charger and I pushed the button it would light up all the leds but any other pushes of the button would not turn on and of the outputs. Guess I have to contact the seller again. Grrrr!
BillWojo