Wacom Cintiq Companion 2

Reference image for the Companion 2 motherboard.

eDP/LVDS connector

Introduction

The Companion 2 utilizes a video controller chip to switch between the Intel Iris eDP (embedded Displayport) input to the internal display and the external HDMI input, which allows the device to be used as an external Cintiq graphics tablet. This chip is a 521 pin BGA Package called Athena STDP9320. Due to the design flaw this chip will die and will always die, even when replaced. I have tested this myself. The exact reason for the death is unknown but it is not heat, as I have even cooled it to test that.

In this tutorial we will remove the Athena and use thin wiring to connect the eDP output from the IGP (Integrated Graphics Processor) to the internal screen directly. We will also need to provide some voltages for the screen to turn on and be recognized. Please note that the Companion will no longer be usable as an external screen without external controllers, that would need to be wired/soldered in.

Symptoms

The following are observed symptoms that occur when the STDP9320 (Athena) is defective.

• Black screen but Windows still runs in the background.
• When turned on the fans start spinning but stop after a short time, Windows did not boot up.
• The Athena STDP9320 gets very hot when attempting to boot the system. When the chip gets very hot there may also be coil whine.
• One or multiple 3.3/1.8/1.2V voltage regulators may reach over 100C while the Athena is defective. This causes thermal shutdown of these components. A failure of these regulators was not observed.
• Before failure the screen may show black bars flickering for short moments.
• If Windows still boots and the internal screen is not recognized at all.

Repair

Required tools and material for this repair.

• Cintiq Companion 2 1310, any variant
• Hot air SMD rework station with small tip soldering iron (1mm)
• Precision Tweezers ~.3mm tip
• Multimeter with precision probe
• Preheater to help remove the chip (Recommended)
• Good magnifying glass or digital microscope and bright light.
• Thin .2mm copper wire. (I suggest isolated wire.)
• Soldering flux
• Advanced skill soldering micro electronics

Removing the STDP9320

Reference for a clean SDP9320 footprint.

STDP9320 pinout with highlighted connections.

Remove the main PCB from the device and also remove all removable components. Place the PCB on the preheater. Cover the PCB with aluminum foil and make a cutout at the Athenas position to protect surrounding components. Preheat the PCB to around 100~150C. Use hot air at 250 to 270C to liquefy the solder and then remove the chip. Be mindful of the small SMD resistors close to the Athena.

Connecting the wires

See the STDP9320 pinout to the right and look at the marked contacts. They are almost all on the left hand side. I also added in a table to show which contacts will need to be connected. Signal in is the output coming from the IGP, out goes to the screen. The voltage pins are used to enable the display and to allow the IGP to detect the screen. LPM_DPTX_HPD comes directly from the screen so you will only measure this if you connect the screen and also connect PBIAS and PPWR first.

Signal IN	Pin	Connect	Pin	Signal OUT
CP0_AUXN	G1	<--->	AF10	DP_AUXTXN
CP0_AUXP	G2	<--->	AG10	DP_AUXTXP
CP0_0P	H1	<--->	AG14	DP_TX0P
CP0_0N	H2	<--->	AF14	DP_TX0N
CP0_1P	J1	<--->	AG13	DP_TX1P
CP0_1N	J2	<--->	AF13	DP_TX1N
CP0_2P	K1	<--->	AG12	DP_TX2P
CP0_2N	K2	<--->	AF12	DP_TX2N
CP0_3P	L1	<--->	AG11	DP_TX3P
CP0_3N	L2	<--->	AF11	DP_TX3N
Voltage IN	PIN	Connect	PIN	Voltage OUT
VDD3V3_DIG	AG7	<--->	AG5	PBIAS (Backlight Power Enable)
VDD3V3_DIG	AG8	<--->	AF4	PPWR (LCD Logic Power Enable)
LPM_DPTX_HPD	E2	<--->	C3	LPM_GPIO10_HPD1 (Hotplug Detect 2,5V)

Measure between the yellow and blue marked pins. You should get continuity only once for each wire. Note: Left goes to IGP and bottom goes to the display.

Quality check

Once you have connected all of the pins you need to check if all solder joints are good. To do this measure between the orange and blue marked resistors. Orange comes from the IGP and blue goes to the screen. Make sure to only get continuity once. If you get continuity between one orange and blue for each wire, then all is good. Make sure there are no unwanted connections, because the signal pins are only rated for 1.3v. When everything is connected like this plug in the screen and turn the system on. If you have made no mistake, then it should work. Even backlight control should function

Troubleshooting

• When you don't get LCD Logic check if PPWR is connected correctly.
• If you don't get BLU_Power check PBIAS for a good connection. Also check if nothing is connected to ground.
• Please note that BIST, COLOR_ENGINE, DBC and H_SYNC are not required for operation and may not be used.
• BL_PWM will only be present, when the backlight is on.
• HPD_OUT will only be present if LCD_VCC is present.
• When you get all voltages but don't get video then you made a mistake while wiring the Signals.
• Windows 10 will automatically switch to tablet mode but you can deactivate that.
• The screen may show corruption when turning on. This is normal, as we are not using the power sequencing from the CPU. The screen immediately displays all input data. Usually the CPU will only activate the LCD when the system is ready to display a signal.
• When the device doesn't turn on and only spins the fan for a few seconds you have shorted something to ground. Likely the VDD3V3_DIG rail.

Use this pinout to check for voltages on the eDP connector while the screen is plugged in.

Used documents

• Athena STDP93XX/STDP73XX Datasheet
• Displayport 1.2 Specification
• Intel Core i7 5557U Specification Volume 1