CM2009 VGA Port Companion Circuit
ESD Protection, Level-Shifting, Buffering and Sync Impedance Matching in a Compact 16-lead QSOP

 

Product Overview
California Micro Devices introduces the CM2009, a highly integrated Application Specific Integrated Passive™ (ASIP™) device that provides a complete interface solution for VGA ports for PCs and set top box applications. The CM2009 provides 7 channels of electrostatic discharge (ESD) protection, level shifting and back drive protection for the DDC signals, and buffers and impedance matching for the SYNC signals. It integrates 22 analog and passive components into a single chip, offering a simple, reliable, space saving and cost effective alternative to discrete implementations. The CM2009 is an ideal solution for notebook and desktop computers, graphics cards, set top boxes and other host platforms that have VGA and/or DVI-I outputs.

The CM2009 is manufactured in a 16-lead QSOP package and is optionally available with lead-free finishing.

Product Features
The CM2009 is placed between the video graphics controller of a PC, graphics card, or set top box, and the analog video output (VGA port or DVI-I port). The CM2009 integrates several critical functions that are typically implemented using many discrete analog and passive devices. These functions include ESD protection, level shifting and back drive protection for the DDC signals, and buffers and impedance matching for the SYNC signals.

All seven channels for video, DDC, and SYNC signals are ESD protected by low capacitance (4pF max) dual rail clamp diodes. These diodes provide ±8kV contact ESD protection per IEC61000-4-2, level 4. ESD protection for the DDC signal pins is designed to prevent back current when the device is powered down while connected to a monitor that is powered up.

Two non-inverting drivers deliver buffering for the HSYNC and VSYNC signals from the video controller IC. Two bidirectional N-channel MOSFETs provide the level shifting function required when the DDC controller is operated at a lower supply voltage than the monitor. Separate positive supply rails for the VIDEO, DDC and SYNC channels facilitate interfacing with low voltage video controller ICs to provide design flexibility in multi-supply voltage environments.

Features of the CM2009 include:

  • ESD protection, level-shifting, buffering and sync impedance matching in a single device
  • 7 channels of ESD protection for all VGA port connector pins meeting IEC-61000-4-2 Level 4 ESD requirements (±8kV contact discharge)
  • Very low loading capacitance from ESD protection diodes on VIDEO lines, 4pF maximum
  • 5V drivers for HSYNC and VSYNC lines
  • Integrated impedance matching resistors on sync lines
  • Bi-directional level shifting N-channel FETs provided for DDC_CLK & DDC_DATA channels
  • Backdrive protection on DDC lines
  • Compact 16-lead QSOP package
  • Available with lead-free finishing

Product Applications
The CM2009 is suitable for a number of applications where space as well as performance are considerations. These include VGA and DVI-I ports in:

  • Desktop and Notebook PCs
  • Graphics Cards
  • Set Top Boxes

Sampling, Pricing and Availability
The CM2009 is currently in production, and pricing starts at $0.85 each in 10,000 units. Lead free packaging options are also available.