LMH1218RTWR from Texas Instruments, in a WQFN-24-EP(4x4). Pinout and pin descriptions extracted from the manufacturer datasheet by ds2sf; symbol, footprint, and 3D from KiCad-official CAD.

Pinout

Pin	Name	Type	Function
1	MODE_SEL	input	4-level input that selects the device host interface. Tie to 1 kΩ→VDD to select SPI mode; other level codes select SMBus / address options (see Initialization Set Up).
2	IN_OUT_SEL_SPI_SS_N_ADR0	input	In SPI mode this pin is SS_N, the SPI slave select input (has an internal pullup, 2-Level). In SMBus mode it is IN_OUT_SEL and ADR0, providing input/output selection and SMBus address bit 0.
3	EQ_SCL_SCK	input	In SPI mode this pin is SCK, the 2.5 V LVCMOS SPI serial clock input. In SMBus mode it is SCL, the SMBus clock, and it can also serve as an EQ strap.
4	OUT_CTRL_MOSI_SDA	bidirectional	In SPI mode this pin is MOSI, the 2-Level SPI master-output/slave-input data receive line. In SMBus mode it is SDA (SMBus data) / OUT_CTRL strap.
5	RESERVED	unconnected	Reserved. No Connect.
6	ENABLE	input	4-Level enable input. 1 kΩ→VDD or Float(Default): power-down until valid signal detected. 20 kΩ→GND: Reserved. 1 kΩ→GND: full power-down including signal detects and register reset on power-up.
7	VDD	power_in	2.5 V ±5% supply input for the device core and I/O.
8	IN1+	input	Noninverting analog differential input of channel 1. On-chip 100 Ω terminating resistor connects IN1+ to IN1-; inputs require 4.7 µF AC-coupling capacitors.
9	IN1-	input	Inverting analog differential input of channel 1. On-chip 100 Ω terminating resistor connects IN1+ to IN1-; inputs require 4.7 µF AC-coupling capacitors.
10	VSS	power_in	Device ground return.
11	IN0+	input	Noninverting analog differential input of channel 0. On-chip 100 Ω terminating resistor connects IN0+ to IN0-; inputs require 4.7 µF AC-coupling capacitors.
12	IN0-	input	Inverting analog differential input of channel 0. On-chip 100 Ω terminating resistor connects IN0+ to IN0-; inputs require 4.7 µF AC-coupling capacitors.
13	LOS_INT_N	output	LVCMOS open-drain, 2-Level programmable interrupt output. Asserts on change in Loss-of-Signal state or violation of the internal eye-monitor threshold. Requires an external 4.7 kΩ pullup; 3.3 V LVCMOS tolerant.
14	SMPTE_10GbE	unconnected	No Connect in SPI mode. In SMBus mode this pin functions as the SMPTE / 10GbE mode strap.
15	VOD_MISO_ADR1	output	In SPI mode this pin is MISO, the 2.5 V LVCMOS 2-Level SPI master-input/slave-output data transmit line. In SMBus mode it serves as VOD strap and SMBus address bit 1.
16	LOCK	output	CDR lock-detect status output, 2.5 V LVCMOS 2-Level. High indicates CDR is locked; low indicates unlocked.
17	RESERVED	unconnected	Reserved. No Connect.
18	RESERVED	unconnected	Reserved. No Connect.
19	OUT0-	output	Inverting 75 Ω CML-compatible differential output of channel 0. On-chip 75 Ω terminating resistor connects OUT0+ and OUT0- to VDD; outputs require 4.7 µF AC-coupling capacitors.
20	OUT0+	output	Noninverting 75 Ω CML-compatible differential output of channel 0. On-chip 75 Ω terminating resistor connects OUT0+ and OUT0- to VDD; outputs require 4.7 µF AC-coupling capacitors.
21	VDD	power_in	2.5 V ±5% supply input.
22	OUT1-	output	Inverting analog differential output of channel 1. On-chip 100 Ω terminating resistor connects OUT1+ to OUT1-; outputs require 4.7 µF AC-coupling capacitors.
23	OUT1+	output	Noninverting analog differential output of channel 1. On-chip 100 Ω terminating resistor connects OUT1+ to OUT1-; outputs require 4.7 µF AC-coupling capacitors.
24	VSS	power_in	Device ground return.
DAP	DAP	power_in	Exposed die-attach pad. Connect to GND with at least 5 vias (see package drawing) for electrical ground and thermal dissipation.

Key specifications

Parameter	Value
Manufacturer	Texas Instruments
Package	WQFN-24-EP(4x4)
Category	Interface
Pins	25

Ordering variants

Same part, different packaging or reel option.

LMH1218RTWR
LMH1218RTWRRTWT

CAD (KiCad official)

Symbol: LMH1218RTWR
Footprint: Package_DFN_QFN:QFN-24-1EP_4x4mm_P0.5mm_EP2.7x2.7mm
3D model: WQFN-24-EP(4x4) (KiCad packages3D, STEP)

Provenance

Data extracted from the manufacturer datasheet, not a distributor listing:

Datasheet: Texas Instruments datasheet (58 pp, sha256 8819557a1c9f9747, retrieved 2026-08-17, tier: lcsc)
Datasheet language: Chinese. Pin names, descriptions, and specs on this page were extracted and translated to English by ds2sf; the linked PDF is the manufacturer original.
Extractor: ds2sf (Claude). Every pin and dimension is cited to a datasheet page; it refuses to fabricate.
CAD: KiCad official libraries (CC-BY-SA 4.0).

Datasheet PDF