Siemens A5E00825002 IGD Board: Industrial Graphics Display Module for Simatic HMIs

The Siemens A5E00825002 is an IGD (Industrial Graphics Display) board, a key component inside certain Simatic HMI operator panels. This PCB (printed circuit board) handles graphics processing, video memory, and interfacing between the main CPU board and the LCD display. It is used as a replacement part for Simatic panels such as the MP277, MP377, and some TP/OP series. The IGD board ensures proper rendering of screen elements, touch response, and backlight control.

Technical Specifications

The A5E00825002 IGD board is built around a dedicated graphics controller (likely an SM502 or similar) with 8 MB of integrated video RAM. It supports resolutions up to 800 x 600 pixels (SVGA) or 640 x 480 (VGA) depending on the panel. The board interfaces with the main CPU via a 40-pin flat ribbon cable and drives the LCD through an LVDS or TTL connector. It also includes a backlight inverter connector (for CCFL or LED). Operating voltage is 5 VDC derived from the main board, consuming 1.5 W typical.

Functionality

The IGD board receives display data from the HMI’s main processor via the parallel ribbon cable. It then generates the necessary timing signals for the LCD panel, performs color mapping (typically 16-bit or 24-bit RGB), and drives the column/row drivers. The board also reads the resistive touch screen coordinates through a separate analog-to-digital converter (typically a 12-bit ADC) and sends the X/Y values back to the main CPU via an I2C or SPI bus. Additionally, it monitors the backlight inverter’s status and provides dimming control.

Compatibility and Installation Notes

The A5E00825002 is a direct replacement for the original IGD board in Simatic MP277 (6AV6644-0AB00-0AA0, etc.) and MP377 (6AV6644-0AB01-0AA0) panels. It may also fit some TP277 and OP277 units. Before installation, verify the panel’s exact type and firmware revision. Installation requires opening the HMI enclosure, disconnecting the old board, and carefully reconnecting the ribbon cables (note alignment). Anti-static precautions are essential. The board is not field-repairable; any further failure typically requires complete panel replacement.

Failure Symptoms and Diagnostics

Common signs of a faulty IGD board include: no display (blank screen but backlight on), distorted or flickering graphics, vertical/horizontal lines, non-responsive touch screen (though touch may work blindly), or the panel rebooting intermittently. The board can be tested by swapping with a known-good unit. Siemens does not provide schematics, but the A5E00825002 is listed as a spare part in the Siemens Spare Parts Catalog.

Environmental and Reliability

The board is designed for industrial environments with operating temperature 0°C to 50°C and humidity 10% to 90% non-condensing. It uses solid-state capacitors for long life. The MTBF is estimated at 50,000 hours. The board is conformal coated to resist moisture and dust (though not fully sealed). It is RoHS compliant and carries the CE mark as part of the original panel assembly.

Ordering and Availability

Order number: A5E00825002. This is a Siemens spare part typically ordered through Siemens industrial distribution channels. The board is supplied as an individual component without cables or mounting hardware. When ordering, provide the serial number of the original panel to ensure compatibility. Siemens documentation (e.g., Repair Manual for MP277) includes a parts list referencing the A5E00825002. Due to product lifecycle, this board may be in limited supply; consider panel upgrade if unavailable.

Important Notes

Replacing the IGD board requires proper ESD protection and mechanical skills. After replacement, the touch screen may need recalibration via the HMI’s control panel. There is no firmware update required for the IGD board itself; it works transparently with the main CPU. For any software-related display issues, first update the HMI image via ProTool or WinCC Flexible. The A5E00825002 is a critical component; always handle by edges and avoid flexing the PCB.