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FPC Cable

Hello guys,
I have a project for my university and I want to modify a mini PCIE to M.2 Adapter with FPC. The point is that I want to know the signals that the cable has. Does anyone know something about it? Thank you!

What does FPC stand for?

To look at what is happening on a cable in general, Oscilloscope (of the storage or mixed-domain type), logic analyzer or signal analyzer.

I feel like @PhaseLockedLoop is the guy to talk to

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Your going to have to give more information or a picture

acronyms are alphabet soup nowadays.

Flexible Printed Circuit is the standard definition
Ahh sorry mobile glitches

So all FPC is referring to is that its a printed circuit within an FFC (Flat Flexible cable). As to the signals in there. you will need the tools maze frame mentioned to decipher what is going where. There is going to be a chipset on this… the gist of it is FPCs are flexible and foldable printed circuits that consist of a layer or multiple layers of copper traces with a polyester base layer. FPCs WILL also have electronic components mounted to its traces and or have them overlapping traces.

In reference to pinouts (should it help you)


Top side (ODD) || Bottom side  (EVEN)
1 	WAKE# 	2 	3.3V
3 	Reserved**** 	4 	GND
5 	Reserved**** 	6 	

7 	CLKREQ# 	8 	VCC**
9 	GND 	10 	I/O**
11 	REFCLK- 	12 	CLK**
13 	REFCLK+ 	14 	RST**
15 	N/C or GND 	16 	VPP**
Mechanical key
17 	Reserved 	18 	GND
19 	Reserved 	20 	Reserved***
21 	GND 	22 	PERST#
23 	PERn0 	24 	+3.3Vaux
25 	PERp0 	26 	GND
27 	GND 	28 	+1.5V
29 	GND 	30 	SMB_CLK
31 	PETn0 	32 	SMB_DATA
33 	PETp0 	34 	GND
35 	GND 	36 	USB_D-
37 	Reserved* 	38 	USB_D+
39 	Reserved* 	40 	GND
41 	Reserved* 	42 	LED_WWAN#
43 	Reserved* 	44 	LED_WLAN#
45 	Reserved* 	46 	LED_WPAN#
47 	Reserved* 	48 	+1.5V
49 	Reserved* 	50 	GND
51 	Reserved* 	52 	+3.3V

NVME M type Key (Supports PCIE x4 (non NGFF))

Number 	Pin
Name 	Description
1 	CONFIG_3 	  Defines module type
2 	3.3 V 	 Supply pin, 3.3 V
3 	GND 	  Ground
4 	3.3 V 	  Supply pin, 3.3 V
5 	PERn3 	  PCIe Lane 3 Rx
6 	N/A 	  
7 	PERp3 	 PCIe Lane 3 Rx
8 	N/A 	 
9 	GND 	  Ground
10 	DAS/DSS 	  Device Activity Signal / Disable Staggered Spinup
11 	PETn3 	  PCIe Lane 3 Tx
12 	3.3 V 	 Supply pin, 3.3 V
13 	PETp3 	 PCIe Lane 3 Tx
14 	3.3 V 	 Supply pin, 3.3 V
15 	GND 	 Ground
16 	3.3V 	 Supply pin, 3.3 V
17 	PERn2 	PCIe Lane 2 Rx
18 	3.3 V 	 Supply pin, 3.3 V
19 	PERp2 	PCIe Lane 2 Rx
20 	N/A 	  
21 	CONFIG_0 	  Defines module type
22 	N/A 	  
23 	PETn2 	 PCIe Lane 2 Tx
24 	N/A 	 
25 	PETp2 	 PCIe Lane 2 Tx
26 	N/A 	 
27 	GND 	  Ground
28 	N/A 	  
29 	PERn1 	  PCIe Lane 1 Rx
30 	N/A 	  
31 	PERp1 	  PCIe Lane 1 Rx
32 	N/A 	  
33 	GND 	  Ground
34 	N/A 	  
35 	PETn1 	  PCIe Lane 1 Tx
36 	N/A 	  
37 	PETp1 	  PCIe Lane 1 Tx
38 	DEVSLP 	 Device Sleep, input. If driven high the host is informing the
SSD to enter a low power state.
39 	GND 	  Ground
40 	N/A 	  
41 	SATA-B+/PERn0 	 Host receiver differential signal pair. If in PCIe mode PCIe Lane 0 Rx
42 	N/A 	  
43 	SATA-B-/PERp0 	 Host receiver differential signal pair. If in PCIe mode PCIe Lane 0 Rx
44 	N/A 	  
45 	GND 	  Ground
46 	N/A 	  
47 	SATA-A-/PETn0 	 Host transmitter differential signal pair. If in PCIe mode PCIe Lane 0 Tx
48 	N/A 	  
49 	SATA-A+/PETp0 	  Host transmitter differential signal pair. If in PCIe mode PCIe Lane 0 Tx
50 	PERST# 	  PCIe reset
51 	GND 	  Ground
52 	CLKREQ# 	  Reference clock request signal
53 	REFCLKN 	  PCIe Reference Clock signals (100 MHz)
54 	PEWAKE# 	  PCIe WAKE# Open Drain with pull up on platform. Active Low.
55 	REFCLKP 	  PCIe Reference Clock signals (100 MHz)
56 	MFG1 	 Manufacturing pin. Use determined by vendor.
57 	GND 	  Ground
58 	MFG2 	 Manufacturing pin. Use determined by vendor.
59-66 	removed 	  Mechanical notch M
67 	N/A 	  
68 	SUSCLK 	  32.768 kHz clock supply input provided by the Platform chipset
69 	CONFIG_1 	 Defines module type
70 	3.3 V 	  Supply pin, 3.3 V
71 	GND 	 Ground
72 	3.3 V 	Supply pin, 3.3 V
73 	GND 	 Ground
74 	3.3 V 	Supply pin, 3.3 V
75 	CONFIG_2 	Defines module type

Naturally in order to convert these its not 1 to 1 you need a chipset or tiny asic…

Thats all the information I can give without knowing more about what you want to know.

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I thought mini-pciE and M.2 pciE were the same, but with a different physical connector?

When I check on Ebay and Aliexpress, I see adapters that exist to convert mini pciE to M.2 (for use with, for example, M.2 wireless cards), which don’t have any IC’s on the PCB.

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They’d have to have something to convert the 1.5v and the 3.3v at the very least


I’ve got a module similar to one of these, and all it has is a couple decoupling caps, so I’m not sure how they’re accomplishing it. They may be excluding circuit pins, idk. Completely passive.

@voula Is this what you’re looking for?

for example, I want to take a product like this

keep the mini pcie side and on the other side of the FPC want to add an only E key m.2 instead of A+E.