CM2030(2012) View Datasheet(PDF) - ON Semiconductor

Part Name

Description

Manufacturer

CM2030
(Rev.:2012)

HDMI Transmitter Port Protection and Interface Device

ON Semiconductor 

CM2030

than 2 kW, and up to 7.3 nF total capacitance.) The CM2030

targets an output drive slew−rate of less than 100 mV/ms

regardless of static load for the CEC line. Additionally, the

same internal circuitry will perform active termination, thus

reducing ringing and overshoot in entertainment systems

connected to legacy or poorly designed CEC nodes.

The CM2030’s bi−directional slew rate limiting is

integrated into the CEC level−shifter functionality thus

allowing the designer to directly interface a simple low

voltage CMOS GPIO directly to the CEC bus and

simultaneously guarantee meeting all CEC output logic

levels and HDMI slew−rate and isolation specifications (See

Figure 5).

CEC

CEC I/F

mP

CM2030

Figure 5. Integrated CM2030 Solution

The CM2030 also includes an internal backdrive

protected static pullup 120 mA current source from the

CE_SUPPLY rail in addition to the dynamic slew rate

control circuitry.

Figure 6 shows a typical shaped CM2030 CEC output

(bottom) against a ringing uncontrolled discrete solution

(top).

Figure 6. CM2030 CEC Output

HDMI certification requires capacitance measurement of

the CEC line to be less than 150 pF per device. Due to the

active circuit inside the CM2030 CEC line, CM2030 may

cause false readings during the CEC capacitance

measurement and not pass the test. The active circuit of the

CM2030 CEC line would react with the LCR meter and

cause false capacitance readings. There is no issue with the

operation of the CM2030 CEC line during normal

operations. In fact, CM2030 CEC has shown to improve the

signal integrity of the CEC line. CM2030 can be used for

applications which do not require HDMI certification or

applications which do not use the CEC line.

HOTPLUG DETECT LOGIC

The CM2030 ensures that the local ASIC will properly

CM2030

detect an HDMI compliant Sink. The current sink maintains

a local logic “low” when no system is connected.

A valid pullup on the HDMI connector pin will overdrive

the internal pulldown and deliver a logic “high” to the local

5V_SUPPLY

LV SUPPLY

ASIC.

HP_IN

IS

HP_OUT

3IS

19

HDMI CONN

Figure 7. Hotplug Detect Circuit

A 15 KW pull down resistor should be connected between

HP_OUT and ground as required by HDMI specification.

There should be no pull up on the HP_IN, ASIC side of

CM2030.

http://onsemi.com

6

Share Link: