No; this is incorrect in English.
First of all, I believe you mean "technician", unless you are referring to a proper noun, i.e. a registered trademark of a company that they use as a label for a position. "TeXnician" is both capitalized as a proper noun and has a capital letter in the middle, which unless it is a use of "geek-capitalization" for a proper noun is also incorrect. If you come from a culture that uses a Greek-derived alphabet, I think you meant X as the Greek letter "chi", which is the correct sound but should be "ch" in this word.
Moving on: the sentence has improper verb tense. In English, the infinitive form "to typeset" should usually only be used after a conjugated verb, and in a few other exceptional cases. Because there is no other conjugated verb between the subject and the infitive, it's wrong. So, you could make the sentence correct by either conjugating the verb in the proper tense, or by adding a properly conjugated verb.
Also, the first-person verb "I am" is commonly used only for simple identification. "I am a technician". Adding the specification behind, "to typeset your document", implies that the speaker is not the only one called. It also sounds like the speaker is referring to himself as an object; such combinations of specific and non-specific identifications are normally made in the second or third person:
This is a tool used to typeset your document.
So, it sounds better if the speaker specifies himself in both clauses; either as "the technician", or "one of the technicians", because the additional phrase "to typeset your document" implies individual specification, calling for use of "the" instead of "a/an".
So, here are some examples of properly-structured sentences that should convey the same meaning.
I am the technician called to typeset your document. (adding a conjugated verb before "to typeset")
I am the technician that will typeset your document. (conjugating "to typeset" in the future perfect)
I am one of the technicians that are typesetting your document. (identifying as one of a group, and present perfect conjugation)
I am a technician. I was called to typeset your document. (removing specification by splitting the statement into an identification and a specification)
EDIT: Taking your "inspiration" into account, I would say that as a rule, active verb conjugation allows the use of the infinitive, and using "to be" to describe something as an adjective, allow use of the infinitive. Identification as a noun does not allow the infinitive to follow.
So, the following are correct:
I am glad to meet you. ("I am glad" is a description, not an identification; you yourself are not the concept of "glad")
I need someone to help me. ("I need someone" is a non-identifying statement, using active voice, so the object "someone to help me" is fine)
... but, "I am someone to help you" is an identification, and thus the object "someone to help you" sounds wrong; it requires conjugation to the proper tense.