HDMI Type A
HDMI Type A is the standard full-size HDMI (High-Definition Multimedia Interface) connector, a 19-pin digital audio/video interface found on televisions, monitors, and AV equipment. Introduced in 2003, HDMI was designed as a single-cable replacement for the multiple analog connections (component video, S-Video, composite video, and separate audio cables) previously required for home theater systems.[1]
In the context of CRT equipment, HDMI inputs are found exclusively on late-model HD CRT televisions manufactured during the mid-2000s, representing the final generation of CRT technology.
History
HDMI was developed by a consortium of major electronics manufacturers — Hitachi, Panasonic, Philips, Silicon Image, Sony, Thomson (now Technicolor), and Toshiba — to create a unified digital interface for consumer electronics. Version 1.0 was released on December 9, 2002, with the first HDMI-equipped products appearing in 2003.[1]
The standard was designed to be backward compatible with DVI (Digital Visual Interface), which had been introduced in 1999 primarily for computer monitors. HDMI added audio transport, CEC device control, and a more compact connector to DVI's existing video capabilities. Simple passive adapters can convert between HDMI and DVI-D for video-only connections.
Design
The Type A connector measures 13.9 mm × 4.45 mm and contains 19 pins. It uses a friction-fit insertion mechanism — there is no locking feature, though the connector's shape prevents incorrect orientation. The specification supports hot-plugging, allowing cables to be connected and disconnected while equipment is powered on.[1]
Specifications
| Parameter | Value |
|---|---|
| Pins | 19 |
| Connector dimensions | 13.9 mm × 4.45 mm |
| Signal type | TMDS (digital video + audio) |
| Maximum bandwidth | Varies by version (4.95–48 Gbps) |
| Audio support | Up to 8 channels PCM, Dolby Digital, DTS, and more |
| Copy protection | HDCP (High-bandwidth Digital Content Protection) |
| Hot-pluggable | Yes |
| Coupling mechanism | Friction fit |
HDMI Versions
HDMI Type A connectors have carried various protocol versions, each expanding bandwidth and feature support:
| Version | Year | Key Features |
|---|---|---|
| 1.0 | 2002 | Up to 1080p/60Hz, 8-channel PCM audio, single-link TMDS (4.95 Gbps) |
| 1.1 | 2004 | Added DVD-Audio support |
| 1.2 | 2005 | Added Super Audio CD (SACD) support |
| 1.3 | 2006 | Deep Color (30/36/48-bit), Dolby TrueHD and DTS-HD Master Audio, lip sync correction (10.2 Gbps) |
| 1.4 | 2009 | 4K/30Hz, 3D support, Audio Return Channel (ARC), Ethernet channel (10.2 Gbps) |
| 2.0 | 2013 | 4K/60Hz, up to 32 audio channels, HDR support (18 Gbps) |
| 2.1 | 2017 | 8K/60Hz, 4K/120Hz, Dynamic HDR, eARC, Variable Refresh Rate (48 Gbps) |
For CRT televisions, only HDMI 1.0 through 1.3 are relevant, as no CRT sets were manufactured after the introduction of HDMI 1.4.
CEC (Consumer Electronics Control)
HDMI includes CEC, a feature allowing interconnected devices to control each other over the HDMI cable. Functions include one-touch play (turning on a TV and switching to the correct input when a source device starts playback), system standby, and volume control pass-through. Different manufacturers market CEC under their own brand names (Samsung Anynet+, Sony Bravia Sync, LG SimpLink, etc.).[1]
Other HDMI Connector Types
| Type | Pins | Size | Primary Use |
|---|---|---|---|
| Type A (Standard) | 19 | 13.9 × 4.45 mm | TVs, monitors, AV receivers, game consoles |
| Type B (Dual-link) | 29 | Larger | Intended for very high resolutions; rarely used |
| Type C (Mini HDMI) | 19 | 10.42 × 2.42 mm | Tablets, DSLR cameras, portable devices |
| Type D (Micro HDMI) | 19 | 6.4 × 2.8 mm | Smartphones, action cameras, small devices |
| Type E (Automotive) | 19 | With locking tab | In-vehicle applications |
Use on CRT Televisions
HDMI inputs appeared on the final generation of CRT televisions produced during the mid-2000s, exclusively on HD CRT models. These sets typically support 480i, 480p, 720p, and 1080i resolutions over HDMI, with the television's internal scaler handling any necessary conversion to the tube's native scan rate.
Notable examples include certain Samsung SlimFit HD CRT models and some Sony WEGA HD CRT televisions from the 2004–2007 era. These sets were among the last CRTs manufactured and represent a bridge between the analog and digital eras of home video.
Because HDMI carries HDCP (High-bandwidth Digital Content Protection) copy protection, some older HD CRT sets with HDMI 1.0 or 1.1 may experience handshake issues with newer source devices, resulting in blank screens or "HDCP error" messages. This is a known limitation of early HDMI implementations.
HDMI and Retro Gaming
While HDMI is a digital interface designed for HD content, it has become relevant to the CRT community through external upscaler/downscaler devices (such as the RetroTINK and OSSC) that convert retro console signals to HDMI, and through HDMI-to-analog converters that can output to CRT-compatible formats. The low-latency characteristics of CRT displays remain desirable for gaming even when digital conversion steps are involved.
See Also
- DE-15 (VGA) — analog VGA connector, predecessor for computer displays
- Component (YPbPr) — analog HD video connection found on the same generation of CRT TVs
- RCA (connector) — consumer analog A/V connector
- SCART — European multi-signal connector
