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HDMI Pinout Explained- Know Your HDMI

HDMI Pinout Explained- Know Your HDMI
Written by prodigitalweb

In this post let us know about HDMI Pinout,  HDMI connector types and more. Totally there are five HDMI connector types. They are A, B, C, D, and E. The types A and B are specified in the HDMI 1.0 version. C type is defined in the 1.3 specifications. Subsequently, in 1.4, specifications D and E are defined. The HDMI pinout and pin configuration of each connector type is defined and remains the same. Therefore they are backward compatible. And there won’t be a compatibility issue.

There are 19 pins in type A. Type B has 29 pins in total. Since connector B carries the second TMDS link, it is a little bulky. It supports very high-resolution displays for those who use dual-link.

Type C is a mini connector. And it is smaller than type A. But have the same 19 pin configuration. Type D is a micro connector similar to the micro USB connector. It has 19 pins. It is similar to types A and C, but the pin assignment is different from both A and B.

Type D is exclusively meant for automotive connection systems. It has a unique locking tab to keep the cable firmly connected. It has 19 contact pins. It is of horizontal pitch, 2-row, 19 position-pins.

The connectors are of impedance matching design. They are compatible with high-speed transmission.

The HDMI pin specification is more important to the manufacturers to make cables and other devices with uniformity.  The particular type of HDMI connectors cannot mate with the connectors of different types. Therefore no issues of cross-connection and having signals on the wrong lines.

HDMI Pinout Explained

Generally, pins 1-12 carry the TMDS data transmission. It includes video, audio, and auxiliary data information. They form four separate channels for video data, clock data.  These data are organized into three categories. They are the Video data period, Data island period, and Control period.

The pins 1-3 carry data channel 2(+ – ground or data shield). The pins 4-6 carry data channel 1(+ – ground or data shield).

The pins 7-9 carry data channel 0(+ – ground or data shield). The pins 10-12 carry the clock data channel that synchronizes the signals (+ – ground or data shield).

Pin 13 carries CEC.  CEC establishes bi-directional communication through this pin. And it can connect and control a maximum of 15 devices. The pins 15- 17 carry DDC data. Pin 14 is kept as reserved for future specification updates. Pin 18 is allotted to use the 5V low voltage power provided by the source device. Pin 19 is for hotplug detection. It will help the device to reinitialize the DDC when you are reconnecting the cables. It monitors power and plugs and unplugs events.

HDMI Pinout Explained

HDMI Pinout:

Type A and Type E Connector Pin Assignment:

Type A is widely used in many applications. It present in TVs, Recorders, Set-top Boxes Blue Ray disc players and more. The male connector of type “A” external dimension is 13.9mmx4.45mm. And the receptacle or female connector’s internal dimension is 14mmx4.55mm. The A-type connector pinout has two rows of pins with alternate numbering down the length of the connector. Therefore the first row starts with the first pin and ends in the 19th pin. Whereas the second row begins with the 2nd pin and ends with the 18th pin. Type A supports all HDTV modes.

Row Pin Number Pin Assignment
Pin 1 TMDS Data2+
First Row Pin 3 TMDS Data2−
Pin 5 TMDS Data1 Shield
Pin 7 TMDS Data0+
Pin 9 TMDS Data0−
Pin 11 TMDS Clock Shield
Pin 13 CEC
Pin 15 SCL  Serial Clock for DDC
Pin 17 Ground (for DDC, CEC, ARC, and HEC
Pin 19 Hot Plug Detect
Pin 2 TMDS Data2 Shield
Second Row Pin 4 TMDS Data1+
Pin 6 TMDS Data1−
Pin 8 TMDS Data0 Shield
Pin 10 TMDS Clock+
Pin 12 TMDS Clock−
Pin 14 Reserved Utility
Pin 16 SDA Serial Data for DDC
Pin 18 +5 V

Type B Connector Pin Assignment:

Type B connector external dimension is 21.2 mm x 4.45 mm. It has 29 pins. And it carries six differential pairs instead of three. This type of connector is used for high-resolution displays. It is designed to support resolutions higher than 1080p. However, the use of the additional three differential pairs is reserved. It is electrically compatible with dual-link DVI D. But, it is not commercially employed in any device. The type B connector is one and half times wider. It can carry twice the data as Type A. Type B is a higher resolution version of type A. The Shell will have the dimple for locking.

Row Pin Pin Assignment
1 TMDS Data2+
3 TMDS Data2-
5 TMDS Data1 Shield
First Row 7 TMDS Data0+
9 TMDS Data0-
11 TMDS Clock Shield
13 TMDS Data5+
15 TMDS Data5-
17 TMDS Data4 Shield
19 TMDS Data3+
21 TMDS Data3-
23 Reserved (N.C. on device
25 SCL
27 DDC/CEC Ground
29 Hot Plug Detect
2 TMDS Data2 Shield
4 TMDS Data1+
6 TMDS Data1-
8 TMDS Data0 Shield
Second Row 10 TMDS Clock+
12 TMDS Clock-
14 TMDS Data5 Shield
16 TMDS Data4+
18 TMDS Data4-
20 TMDS Data3 Shield
22 CEC
24 Reserved (N.C. on device)
26 SDA
28 +5V Power

Type C Connector Pin Assignment:

It is a mini connector. And it is smaller than the TypeType A.  The plugs’ external dimension is 10.42mmx2.42mm. The Shell of the connector has a spring for locking. Additional springs may be used for EMI reduction. The spring property for locking shall be activated by the locking hole of the plug shell.  It also has the same 19 pin configuration as like Type A.

The only difference is it is meant for portable devices. Therefore all positive signals of the differential pairs are swapped with their corresponding shields. The CEC ground is assigned to pin 13. Besides, CEC is assigned to 14 instead of pin 13. Pin 17 is reserved. The Type C Mini connector can be connected to a type A connector using a type A-to-type C cable.

Row Pin Pin Assignment
1 TMDS Data2 Shield
3 TMDS Data2-
5 TMDS Data1+
7 TMDS Data0 Shield
9 TMDS Data0-
First Row 11 TMDS Clock+
13 DDC/CEC Ground
15 SCL
17 Reserved
19 Hot Plug Detect
2 TMDS Data2+
4 TMDS Data1 Shield
6 TMDS Data1-
Second Row 8 TMDS Data0+
10 TMDS Clock Shield
12 TMDS Clock-
14 CEC
16 SDA
18 +5V Power

Type D Connector Pin Assignment:

Row Pin Pin Assignment
1 Hot Plug Detect
3 TMDS Data2+
5 TMDS Data2-
7 TMDS Data1 Shield
First Row 9 TMDS Data0+
11 TMDS Data0–
13 TMDS Clock Shield
15 CEC
17 SCL
19 +5V Power
2 Utility
4 TMDS Data2 Shield
6 TMDS Data1+
8 TMDS Data1-
Second Row 10 TMDS Data0 Shield
12 TMDS Clock+
14 TMDS Clock–
16 DDC/CEC Ground
18 SDA

Connector Contact Sequence:

Connection Type A & C Connectors Type B Connector Type D Connector Type E Connector
First Make Connector shell Connector shell Connector shell Connector shell
Second Make Pins 1 – 17 and pin 19 Pins 1 – 27 and pin 29 Pins 1 – 18 Pins 1 – 19
Third Make Pin18 (+5V Power) Pin28 (+5V Power) Pin19 (+5V Power)


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