mini sd Card socket pinout Q - Page 1
Forum section: electronics / projects

author: RuddyCrazy
author_rank: Newbie
timestamp: June 07, 2011, 07:16:01 am
content: Hi Guy's,I'm on making a smd breakout board for a mini SD card socket that suits a micro SD card. The mini socket has 11 pins and after some research I reckon I got it right but I would like to check if the pinouts are correct before I make a board.Anyway the pinouts I did from the 11 pin mini slot reader to the micro sd card11 pin___________8 pinpin 1____________ Pin 1 chip selectpin 2____________Pin 2 DIpin 3____________Pin 3 Gndpins 4,5,6_______N/Cpin 7____________ Pin 4 Vddpin 8____________ pin 5 Clockpin 9____________ pin 6 Gndpin 10___________ pin 7 DOpin 11___________ pin 8 N/CThe card detect is on the side of the socket and I put a trace to ground. Now the write protect isn't on so I do suppose if it's left out it shouldn't be a problem but is it Vdd or ground for write protect ?Cheers Bryan

author: KeithBrown
author_rank: Contributor
timestamp: June 09, 2011, 10:36:42 pm
content: What you seem to be referring to is the SPI Signal Interface mode pins. I don't think you have the 11 pin (miniSD) columns correct, and you seem to have different problems with the 8 pin column (microSD). On the miniSD, in the SPI Mode, pins 8 and 9 are Unused and 10 and 11 are reserved (basically means the same thing). Now you say that you are making the board for a miniSD socket "that suits a micro SD card"--I don't follow what you mean here. Are you simply plugging in either a miniSd, or, a microSD in an available adapter (they often come with them) or is there a socket type which will accept either size? Giving us part numbers is always good!My take on it this (based on what I found atwww.interfacebus.com):MiniSD-11 pin name -- function MicroSD-9 pin1............CD -- chip select..........22............DI -- MOSI..................33............Vss --Gnd...................64............Vdd --V+....................45............CLK--serial clock..........56............Vss --Gnd7............DO -- MISO.................78............unused.......................19............unused10...........reserved.....................811...........reservedAlso, are you sure you can omit the card detect: how will software know to set up for a new card or delete buffers etc when a card is removed?And the Write protect is usually a switch to ground that is activated if and only if the card's write protect slide is in the corresponding position, so to answerthatquestion: ground (probably--but check the socket to be 100 % sure).

author: RuddyCrazy
author_rank: Newbie
timestamp: June 13, 2011, 07:25:08 am
content: Hi Keith,Thanks so much for pointing out the error on the pinouts, I did go and research on that link you gave and YEP you are right. The card detect is the last pin and the square pad. The micro sd card doesn't have a write protect so I'll tie the micro output to Vdd. I made up the board today along with a mini usb type B board and later this week i'll drill and solder both sockets on. Then with a bit more work I'll be ready to program in the maximite code and have my own homebrew version to play with.Thanks again mateCheers Bryan