STMicroelectronics HDMIULC6-4SC6

Overview

HDMIULC6-4SC6 from STMicroelectronics is a monolithic 4-line ESD protection device for high-speed differential interfaces, featuring 15 kV air/8–15 kV contact ESD immunity per IEC 61000-4-2 Level 4, 1 pF I/O-to-GND capacitance at 1 MHz, 0.5 µA max leakage, and ultra-high 5.3 GHz cutoff frequency-designed specifically for HDMI 1.3+ (up to 3.2 Gb/s), USB 2.0, IEEE 1394, and Gigabit Ethernet ports.

For engineers reviewing the HDMIULC6-4SC6 datasheet, HDMIULC6-4SC6 pinout, HDMIULC6-4SC6 application, or HDMIULC6-4SC6 equivalent, key selection criteria include differential pair capacitance matching (±0.015 pF variation), VBUS isolation capability in HDMI layouts, clamping voltage ≤17 V at 5 A (8/20 µs), and SOT23-6L footprint compatibility with 100 Ω controlled-impedance routing.

Technical Context

The HDMIULC6-4SC6 employs a rail-to-rail diode topology combining low-capacitance ESD clamps between each I/O line and GND, plus a dedicated VBUS-to-GND Transil structure. Its design ensures simultaneous protection of four signal lines while maintaining <0.3 pF inter-pair capacitance at 825 MHz and <0.007 pF variation-critical for minimizing intra- and inter-pair skew in TMDS channels.

Unlike varistor-based protectors, it delivers sub-nanosecond response time and guarantees system-level ESD immunity without degrading signal integrity: measured S21 attenuation remains >−3 dB up to 3.2 Gb/s, and differential impedance deviation is suppressed via matched I/O capacitance (0.42–0.5 pF at 1 MHz, 0.3 pF at 825 MHz).

Key Specifications

Pinout & Package

SOT23-6L package (JEDEC MO178AB), 3.05 × 1.75 × 1.30 mm, 9 mm² footprint, RoHS-compliant ECOPACK® with lead-free terminations.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar high-speed interface ESD protection applications.

Compared with SP1006-04UTG and ESD7L5.0DT5G, the HDMIULC6-4SC6 uniquely integrates VBUS clamping, achieves superior inter-pair capacitance matching (0.007 pF vs. ≥0.02 pF), and delivers guaranteed 3.2 Gb/s signal integrity-making it the only option qualified for HDMI 1.3+ and IEEE 1394c compliance out-of-the-box.

Availability

HDMIULC6-4SC6 is available at Aetrix Electronics and suitable for HDMI video transmission systems, USB 2.0 peripheral interfaces, and Gigabit Ethernet PHY protection requiring stable component supply across consumer electronics, industrial displays, and embedded multimedia platforms.

Supply support for HDMIULC6-4SC6 includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

STMicroelectronics is a global semiconductor leader headquartered in Geneva, Switzerland, designing and manufacturing microcontrollers, analog ICs, power management devices, and discrete protection components for automotive, industrial, and consumer markets.

The HDMIULC series targets high-speed interface protection, engineered specifically to meet stringent ESD immunity and signal integrity requirements of HDMI, USB, IEEE 1394, and Ethernet physical layers-prioritizing ultra-low capacitance, precise inter-pair matching, and rail-to-rail topology.

FAQ

What is the recommended PCB layout for HDMIULC6-4SC6 in HDMI applications?

Place the device within 3 mm of the HDMI connector with shortest possible traces: I/O pins routed differentially (100 Ω impedance), GND connected directly to solid ground plane, and Pin 4 (VBUS) left unconnected to prevent backdrive current. Avoid vias in signal paths and use symmetric trace lengths to maintain skew <0.1 ps.

Can HDMIULC6-4SC6 be used for HDMI 2.0 or 2.1 interfaces?

No-HDMIULC6-4SC6 is characterized and validated up to 3.2 Gb/s (HDMI 1.3 bandwidth). HDMI 2.0 (6 Gb/s) and 2.1 (12–48 Gb/s) require lower capacitance (<0.2 pF) and higher bandwidth (>10 GHz), which this device does not provide; ST recommends newer solutions like ESDAXXX series for those standards.

Why is Pin 5 (I/O3) not connected in standard HDMI implementations?

In single-link HDMI (TMDS clock + three data lanes), only Pins 1–4 are used (I/O1/I/O2 for Data0, GND, VBUS). Pin 5 (I/O3) and Pin 6 (I/O4) are reserved for second differential pair (e.g., Data1) and remain unconnected unless dual-link or custom multi-lane configurations are deployed-preventing unintended signal coupling.

How does the rail-to-rail topology improve ESD protection compared to standard diode arrays?

Rail-to-rail architecture provides independent low-impedance paths from each I/O line to both GND and VBUS, enabling simultaneous clamping of positive and negative transients without forward-biasing adjacent lines. This eliminates crosstalk-induced false triggering and ensures <1 ns response-critical for preserving signal integrity during multi-pin ESD events.