AD584LH 4 output voltage reference not working - Page 1
Forum section: electronics / testgear

author: BillWojo
author_rank: Regular Contributor
timestamp: September 16, 2014, 01:43:35 am
content: 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

author: BillWojo
author_rank: Regular Contributor
timestamp: September 16, 2014, 02:05:49 am
content: Just opened it up, battery is sitting just below 3VDC. Looking all over for a wallwart, Can't find a darn 5VDC unit.BillWojo

author: radhaz
author_rank: Regular Contributor
timestamp: September 16, 2014, 02:56:41 am
content: 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

author: BillWojo
author_rank: Regular Contributor
timestamp: September 16, 2014, 04:03:06 am
content: 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.ThanksBillWojo

author: BillWojo
author_rank: Regular Contributor
timestamp: September 16, 2014, 12:57:08 pm
content: 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 againBillWojo

author: Andreas
author_rank: Super Contributor
timestamp: September 16, 2014, 08:48:46 pm
content: Hello,is there really a AD584LH populated?Analog Devices does only produce JH and KH grades according to the latest data sheet.With best regardsAndreas

author: Andreas
author_rank: Super Contributor
timestamp: September 16, 2014, 09:07:02 pm
content: Quote from: gazelle on September 16, 2014, 08:53:46 pmThanks,The latest datasheet change was 05/2012 so the datecode on the LH device should be before this date.With best regardsAndreas

author: Co6aka
author_rank: Unknown
timestamp: September 17, 2014, 02:54:05 am
content: Quote from: Andreas on September 16, 2014, 08:48:46 pmIf 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.

author: BillWojo
author_rank: Regular Contributor
timestamp: September 19, 2014, 09:58:47 pm
content: 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