72C5 - What Is This? - Page 1
Forum section: electronics / beginners

author: Trurl
author_rank: Regular Contributor
timestamp: April 24, 2024, 05:08:11 pm
content: What is the followingthing?My measurement of it is about 1.6mm(L) x 0.75mm(W). It is found in the Gen 9 Flex Slot Server PSU - HP HSTNS-PD43 (DPS-1400CB A).I searched all over the place and all I could find for the marking "72C5" were SMD parts starting with "72". Among those I was only able to find one part with similar dimensions - a Galaxy Electrical 'Small Signal MOSFET Transistor' (datasheet below)72 2n7002t_galaxy.pdf(194.2 kB - downloaded 89 times.)Is the part in the datasheet the correct part or is there something I'm missing?

author: amyk
author_rank: Super Contributor
timestamp: April 25, 2024, 03:48:02 am
content: How is it connected to other components? A bigger picture of its surroundings?

author: floobydust
author_rank: Super Contributor
timestamp: April 25, 2024, 04:20:27 am
content: PossiblyPanjitBAT721C SMD marking code "72C" dual Schottky diode.

author: Trurl
author_rank: Regular Contributor
timestamp: April 25, 2024, 08:19:43 am
content: The photo above shows the side(auxiliary) board of the PSU with one of the "72C5" parts towards the center(use slider at bottom of this post to move to the center of the photo). I've marked the connections as follows;Pin 1 (Blue) : Adjacent via connects to Microchip dsPIC33FJ64GS606 pin 26 (VDD) (towards the right side of the photo)Pin 2 (Yellow) : Connects via resistor "91B" to the LM393* opamp's pin 5("+" non-inverting input)Pin 3 (Red) : Via connects to the +12VDC main output of the PSU*Side Note: The LM393's opposite(upper) side opamp is associated with the OVP(Over Voltage Protection)Image from Hopper's hack on YouTube ("HP HSTNS-PD43, Hacked, OVP, 15.5 VDC")Adding a resistor between the 393's pin 3(or lower solder point of resistor "05C" on pin 3's 1 o'clock direction, for easier soldering) and a convenient ground point, alters the sensed OVP voltage allowing a boost of the main output voltage from 12V to say 14~15V.The voltage can be increased by adding a resistor between the variable pot's upper left pin(or the adjacent capacitor's upper solder point for easier soldering as these two points are connected) and ground(e.g. the 5th exposed copper land shaped like a "Q" among the series of lands, right of the variable pot).I've probed and traced this side board's key circuits and intend to share the partial schematic once I get my sketches transferred into a schematic software, for more interesting discussions...Thanks in advance... Cheers...

author: Trurl
author_rank: Regular Contributor
timestamp: April 29, 2024, 10:01:15 am
content: I think I've found the right bugger!72C5 (MOSFET N-ch) 2N7002T DIODES.pdf(435.29 kB - downloaded 49 times.)It's reassuring that this is also an N-channel MOSFET (2N7002T), and it's produced by a more recognizable manufacturer, Diodes Inc. with a datasheet that includes a detailed "Marking Information" section;Marking Information"72 YM"72 = Product Type Marking CodeYM = Date Code MarkingY = Year (ex: H = 2020)M = Month (ex: 9 = September)Hence, "72C5" = product 72 produced in 2015("C"), May ("5") - which seems about right for the used Gen 9 HP server PSU I'm fiddlin' with.The following site has been the best I've encountered so far for searching SMD codes:www.repaircompanion.com/smd_code_searchCheers~