If you are arrested for drunk driving in Texas your driver's license will be suspended immediately. The police officer will confiscate your license and issue you a temporary driving permit, which is good for 40 days. Your license will be suspended for 90 days if you failed the breath test on a first offense and for 180 days on a first-time test refusal.
The license suspension at the time of arrest is an administrative matter separate from the criminal proceedings on the drunk driving charges. You have the right to appeal the suspension by requesting a hearing before the Texas Department of Public Safety. You have 15 days from the date you receive notice of the suspension - which usually means the date of arrest - to request the hearing. If you do not request a hearing within 15 days you will lose your right to appeal.
The hearing is heard by an administrative law judge and has no effect on the criminal drunk driving case. If your license was suspended for failing the breath test the issues are limited to whether the officer had a reasonable suspicion to justify pulling you over, whether the officer had probable cause to arrest you and whether the test showed a blood alcohol level of 0.08 or more or, if you were a minor on the date you were arrested, whether you had any alcohol at all in your system.
If your license was suspended for a test refusal, the issues at the hearing are limited to whether there was reasonable suspicion or probable cause for the stop or arrest, and whether you were requested to take a breath test and refused. Whether the suspension was for failing the test or refusing to take it, your chances of having the suspension lifted and your license reinstated are better if an experienced DWI defense attorney represents you at the hearing.
Source: statutes.legis.state.tx.us, "Tex. Trans. Code ch. 524," accessed Feb. 8, 2015