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Electronics Repair (sci.electronics.repair) Discussion of repairing electronic equipment. Topics include requests for assistance, where to obtain servicing information and parts, techniques for diagnosis and repair, and annecdotes about success, failures and problems. |
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Harris IC ID
I have a PCB with a part marked:
H721A F749AMD It's an 8 pin SOIC, with power (+5 VDC) at pin 8 and GND at pin 4. Could be an op-amp or TTL based on expected function. I'm assuming Harris - the "H" is a bit bolder than the rest. Only a few years old, not ancient. Google seems to have no clue except that the H721A has been asked about on a sci* group in the past, apparently without a solution. It really shouldn't be anything unusual or custom, Some of it's pins are connected to the outside world via 100 ohm series resistors. Part of an interlock on a laser. Any info appreciated. Thanks! -- sam | Sci.Electronics.Repair FAQ: http://www.repairfaq.org/ Repair | Main Table of Contents: http://www.repairfaq.org/REPAIR/ +Lasers | Sam's Laser FAQ: http://www.repairfaq.org/sam/lasersam.htm | Mirror Sites: http://www.repairfaq.org/REPAIR/F_mirror.html Important: Anything sent to the email address in the message header above is ignored unless my full name AND either lasers or electronics is included in the subject line. Or, you can contact me via the Feedback Form in the FAQs. |
#2
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Harris IC ID
On 30 Jan 2009 11:42:30 -0500, (Samuel M.
Goldwasser) put finger to keyboard and composed: I have a PCB with a part marked: H721A F749AMD It's an 8 pin SOIC, with power (+5 VDC) at pin 8 and GND at pin 4. Could be an op-amp or TTL based on expected function. I'm assuming Harris - the "H" is a bit bolder than the rest. Only a few years old, not ancient. Google seems to have no clue except that the H721A has been asked about on a sci* group in the past, apparently without a solution. It really shouldn't be anything unusual or custom, Some of it's pins are connected to the outside world via 100 ohm series resistors. Part of an interlock on a laser. Any info appreciated. Thanks! FWIW, I found this tiny snippet of info on a part that may be related to the H721A: http://www.partminer.com/spdetail/H723A H723A IC,ESD/OVERVOLT PROTECT,S H723A SOP-8P INTERSIL Another clue may be this post: http://www.sxlist.com/techref/postbo...C 071335a.txt The author writes: "I'm trying to find the manufacturer of a IC in the PicStart board, it's a SO8 dual SPST switch and it's marked H721A. I've found the analog device ADG721, but I'd like to know others manufacturers." Microchip's PicStart manual states that the "PICSTART Plus development programmer features ... special circuit design techniques to enhance ESD protection." Here is the datasheet for the ADG721/722/723: http://www.datasheetarchive.com/pdf-.../DSA-70382.pdf It states that "the ADG721/ADG722/ADG723 features proprietary ESD protection circuitry". The part is described as a "CMOS Low Voltage 4V Dual SPST Switch". I suspect that the H721A is in fact compatible with the ADG721. - Franc Zabkar -- Please remove one 'i' from my address when replying by email. |
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