Trying to identify a smd. Markings GD 1B

[magnetchief]

hi,
I am attempting to repair a small temperature control device.
I noticed that a small smd on the circuit board had blown.
Attached is a photo of the device, There are very few markings and have so far drawn a blank searching online.
Much appreciated,

[Jbouss]

It may be possible to figure out what the IC is by what it is traced to. I suggest attaching a picture of the full board; you could go a step further and draw out what is attached to each pin.

Good luck!

[amyk]

Does RT8010-15GQW match? https://www.s-manuals.com/ru/smd/gd

[magnetchief]

Many thanks. 
Will try that

[magnetchief]

Attached is the whole board.
It is a temperature control device, 2 thermocouples, a heater and a heater  safety sensor device (a PT100 sensor to measure heater temp)

The yellow wire (U1+) shows the small pad where the damaged part was removed.

Unfortunately I do not have the skill required to describe its function within the circuit.

Many thanks for any advice.

[amyk]

Definitely not RT8010 or any other switching regulator.

[mvs]

Unfortunately I do not have the skill required to describe its function within the circuit.

It is an ESD protection clamp, similar to Semtech RClamp3354S
https://www.semtech.com/products/circuit-protection/low-capacitance/rclamp3354s

The clamp near LN2 T1 and T2 pads seems to be unused. You can salvage it for a repair.

[magnetchief]

Many thanks, I will give that a go.