Is mSATA electrically compatible with Mini PCIe?

Not by default. The cards use the same 52-position mechanical connector, but mSATA carries SATA while Mini PCIe carries PCI Express and USB. A socket must explicitly support the inserted card type.

Can an mSATA SSD be installed in an M.2 slot?

No direct insertion is possible because mSATA and M.2 use different connectors and mechanical formats. An adapter may work only when it routes a supported SATA interface and meets power and mechanical requirements.

Which mSATA pins carry the SATA differential pairs?

Pins 23 and 25 are the host receive pair, connected to the device transmitter. Pins 31 and 33 are the host transmit pair, connected to the device receiver.

52-position card-edge reference

mSATA Pinout & Mini PCIe Compatibility

Locate the SATA pairs, power rails, grounds, and detection pins, then verify whether a physically matching Mini Card socket actually supports mSATA.

Guide Published Jul 14, 2026 Pinout traced to SATA-IO ECN045

Same connector does not mean compatible

mSATA and PCI Express Mini Card share a 52-position mechanical form, but they carry different high-speed protocols. Install an mSATA SSD only when the host manual or schematic explicitly documents mSATA or a switchable dual-purpose socket.

Connector view

Complete 52-pin map

SATA pair Power Control Ground

Odd sideEven side

1 NC

2 +3.3 V

3 NC

4 GND

5 NC

6 +1.5 V

7 NC

8 NC

9 GND

10 NC

11 NC

12 NC

13 NC

14 NC

15 GND

16 NC

17 NC

18 GND

19 NC

20 NC

21 GND

22 NC

23 Host RX+ / device TX+

24 +3.3 V

25 Host RX- / device TX-

26 GND

27 GND

28 +1.5 V

29 GND

30 Two-wire clock

31 Host TX- / device RX-

32 Two-wire data

33 Host TX+ / device RX+

34 GND

35 GND

36 NC

37 GND

38 NC

39 +3.3 V

40 GND

41 +3.3 V

42 NC

43 mSATA socket detect (NC)

44 NC

45 Vendor-specific

46 NC

47 Vendor-specific

48 +1.5 V

49 Device activity / DSS

50 GND

51 Presence detect (device GND)

52 +3.3 V

Logical connector map, not a footprint-placement drawing. Confirm orientation and pad numbering against the selected connector drawing before layout.

Key signals

23 / 25: Host RX+ / RX-, driven by the SSD TX pair.
31 / 33: Host TX- / TX+, received by the SSD.
2 / 24 / 39 / 41 / 52: +3.3 V supply contacts.
6 / 28 / 48: +1.5 V contacts defined by the connector mapping.
43 / 51: Socket-type distinction and card presence behavior.

No hot-plug assumption

The cited mSATA connector definition does not support hot insertion or removal. Power down the host before changing the card unless the complete platform documentation states otherwise.

mSATA, Mini PCIe, and M.2 compatibility

Card / socket	Mechanical fit	Electrical interface	Result
mSATA card in mSATA socket	Yes	SATA routed to the 52-pin socket	Expected match
mSATA card in Mini PCIe-only socket	Often yes	PCIe / USB, not SATA	Not compatible
Mini PCIe card in mSATA-only socket	Often yes	SATA, not PCIe / USB	Not compatible
Either card in documented dual-purpose socket	Yes	Host detects or switches the routed interface	Platform-specific
mSATA card in M.2 socket	No	Different connector and pin map	Requires a suitable adapter and host SATA support

Verification workflow

Read the host manual for explicit mSATA, Mini PCIe, or dual-mode wording.
Inspect the schematic for SATA differential pairs on pins 23/25 and 31/33.
Confirm the power rails, enable sequencing, detection method, and connector orientation.
Check BIOS or firmware settings that may select the socket function.
Power down before insertion, then verify enumeration and link status.

Layout notes for a host design

Route each SATA pair to the impedance and intra-pair skew targets supplied by the platform and fabricator.
Keep return paths continuous and place coupling capacitors exactly as required by the SATA implementation guidance.
Use the connector manufacturer's footprint, keepout, and insertion drawings rather than reconstructing pads from this logical map.
Validate supply current, bulk capacitance, reset behavior, and device activity indication for the chosen SSD.

Frequently asked questions

Why can an mSATA card fit a Mini PCIe socket?

The standards reuse the same mechanical card-edge form. The pin functions and high-speed protocol differ, so physical insertion is not proof of electrical support.

Does pin 43 identify an mSATA socket?

ECN045 revised pin 43 to a no-connect condition that a host can use as part of distinguishing an mSATA socket from a non-mSATA socket. Follow the actual platform detection circuit.

Is mSATA the same as M.2 SATA?

They can both transport SATA, but they use different connectors, mechanics, and pin assignments. A passive adapter is only viable when the host side already exposes the required SATA interface and correct power.

Primary references

SATA-IO ECN045: mSATA Connector - the accessible ECN/draft used for this logical map. Production designs should also use current member specifications and platform documentation.
PCI-SIG: PCI Express Mini Card Electromechanical Specification - official specification landing page for the mechanically related Mini Card format.