Ufs 3.1 Pinout
(Note: Some early UFS implementations used a VCCQ rail for the controller and VCCQ2 for the PHY, but modern UFS 3.1 BGA packages generally consolidate these into the standard VCC and VCCQ2 configuration.)
For hardware design: Route the differential pairs (RX/TX) with 50-ohm impedance matching and length matching within 5 mils. Keep REF_CLK away from switching regulators to avoid jitter.
For phone repair: If a water-damaged phone doesn't detect UFS, measure diode mode to ground on VCC, VCCQ, and REF_CLK. A short to ground on REF_CLK often indicates a cracked chip or solder bridge under the BGA.
For data recovery: Using a UFS adapter board (e.g., EasyJTAG, Medusa Pro), you need to map the pinout correctly. Misconnecting VCCQ (1.2V) to a 3.3V programmer port is a common cause of permanent chip death.
UFS 3.1 pinout varies slightly by vendor. Search for the datasheet using:
Request: “BGA 153 ball map” + “UFS 3.1 pin assignment” from vendor’s NDA documentation.
| Feature | UFS 3.1 | eMMC 5.1 | | :--- | :--- | :--- | | Interface | Differential serial (M-PHY) | Parallel (8-bit) | | Pins used for data | 4 or 8 (RXP/N, TXP/N x2) | 12-16 (CMD, CLK, DAT[0:7]) | | Voltage | 1.2/1.8/3.3V | 1.8/3.3V | | Full duplex | Yes | No | | Minimum pin count for operation | 7 (VCC, VCCQ, GND, CLK, RX±, RST) | 9 (VCC, VCCQ, GND, CLK, CMD, DAT0) |
The UFS 3.1 pinout represents a sophisticated leap from the parallel legacy of eMMC. By utilizing differential serial lanes (DATAIN/OUT), a dedicated reference clock (REFCLK), and dual-voltage power rails (VCC and VCCQ2), UFS 3.1 achieves the bandwidth necessary for 4K video recording, high-speed app loading, and rapid file transfers. ufs 3.1 pinout
Whether you are a PCB designer implementing a storage subsystem or a technician performing board-level repairs, understanding that UFS requires a host-generated clock and strict differential pair integrity is the key to successfully working with this technology.
Universal Flash Storage (UFS) 3.1 is a high-performance storage interface standard commonly used in modern smartphones and automotive systems to provide high-speed data transfer and improved power efficiency. Common UFS 3.1 Pinout Configurations
UFS 3.1 chips typically use a Ball Grid Array (BGA) package, with the most common being BGA 153 and BGA 254. 1. BGA 153 Pinout (Standard Mobile/Embedded)
UFS 3.1 | Universal Flash Storage | Samsung Semiconductor Global
UFS 3.1 | Universal Flash Storage | Samsung Semiconductor Global. samsung.com
UFS 3.1 (Universal Flash Storage) uses a high-speed serial interface based on the MIPI M-PHY physical layer and UniPro transport layer. The pinout typically consists of differential pairs for data transmission, a reference clock, a reset signal, and various power supply rails. Core Interface Pins
UFS 3.1 utilizes a low pin-count interface that supports full-duplex operation (simultaneous read/write). Data Lanes (M-PHY): (Note: Some early UFS implementations used a VCCQ
TX_P / TX_N (Lane 0 & 1): Differential transmit pairs from the host to the UFS device.
RX_P / RX_N (Lane 0 & 1): Differential receive pairs from the UFS device back to the host.
Note: UFS 3.1 commonly supports 2-lane configurations for a maximum raw data rate of approximately 2.9 GB/s total (Gear 4). Clock and Control: REF_CLK: A reference clock signal provided by the host. RST_N: Hardware reset signal (active low). Power Supply Rails
Typical UFS 3.1 devices require three distinct power supplies to balance performance and power efficiency. Voltage Range Description VCC 2.7V – 3.6V Main power for NAND flash operations. VCCQ 1.14V – 1.26V High-speed I/O power (standard for UFS 3.x). VCCQ2 1.70V – 1.95V Power for the controller and auxiliary logic. Standard Packages
UFS 3.1 chips are generally available in standardized Ball Grid Array (BGA) packages:
BGA-153: A 153-ball package commonly used for high-capacity mobile storage.
BGA-254: Often used in Multi-Chip Packages (uMCP) where UFS and LPDDR RAM are integrated. Key Features impacting Electrical Interface For hardware design: Route the differential pairs (RX/TX)
DeepSleep: A low-power state introduced in UFS 3.1 that allows the device to share voltage regulators with other components to save costs and power.
Performance Throttling Notification: A signal-level protocol that allows the UFS device to inform the host of thermal issues. MIPI M-PHY | MIPI
For PCB designers working with UFS 3.1, the pinout dictates strict layout rules due to the high frequencies involved (up to 11.6 Gbps per lane in Gear 4).
UFS 3.1 supports up to two lanes. Lane 0 is mandatory; Lane 1 is optional but required for maximum performance.
| Signal Group | Pin (Lane 0) | Pin (Lane 1) | Description | Differential Impedance |
| :--- | :--- | :--- | :--- | :--- |
| TX (Device to Host) | R1 (DOUT_T0_P)
R2 (DOUT_T0_M) | M1 (DOUT_T1_P)
M2 (DOUT_T1_M) | Device Transmit to Host. Positive (P) and Negative (M) diff pair. | 100Ω ±10% |
| RX (Host to Device) | T2 (DIN_T0_P)
T3 (DIN_T0_M) | P1 (DIN_T1_P)
P2 (DIN_T1_M) | Device Receive from Host. Positive and Negative diff pair. | 100Ω ±10% |
| REF_CLK | K1 (REF_CLK_P)
K2 (REF_CLK_N) | N/A | Differential reference clock (19.2 MHz, 26 MHz, or 38.4 MHz) from host. | 100Ω |
Critical Note on Pin Names: Different manufacturers (Samsung, Kioxia, SK Hynix) may rename these. Common alternatives:
The 153 balls are arranged in a 13x13 grid, but many center balls are omitted or reserved. The key functional groups:
| Group | Balls | Description | |-------|-------|-------------| | Power | A1, A2, B1, B2, etc. | VCC (NAND), VCCQ (I/O & Controller), VCCQ2 (optional 1.8V) | | Ground | Multiple | VSS | | UFS Interface | C3, C4, D3, D4 | D0_RX, D0_TX, D1_RX, D1_TX (two lanes) | | Control | A4, A5 | REF_CLK, RST_N | | Boot/Init | B3 | C/D (Boot mode / configuration) |
