Using implantable medical devices for gathering biometric data, diagnosis and also constant patient monitoring have been growing fast during last decades. In the late 50s, this field has drawn many attentions and researchers tried to design and realize implantable medical devices to measure and gather the vital sensory data from inside the body and even using proper stimulators to emulate the human body activities. These techniques can play an important role to treat some diseases that do not respond properly to the pharmaceutical drug treatments. As the most commonexample of such devices it can be pointed out to the implanted cochlear device which is vastly used by patients who suffer from hearing problems. One of the most important blocks in such implantable devices is the transmitterpart. This part transmits the sensory data from inside the body to the outside world where itis gathered through a proper reader device. This part is subject to many important challenges such as power consumption, transmission data rate, circuit complexity, cost, and so on. In this thesis, an ultra-wide band (UWB) transmitter with impulse like signals in a fully differential structure is designed and simulated in a 180 nm CMOS process. The transmitter consists of an impulse generator, a programmable delay block, and a two-stage differential oscillator. Four control bits are used to control the center oscillation frequency and two bits are used to modify the triggering pulse width; this controls the output power of the system depending on the environmental changes in terms ofprocess, temperature and voltage variations. The generated pulse center frequency can be tuned in the range of 3.2 GHz to 5 GHz. Also, the trigger pulse width can be set between 1 nsec to 2.5 nsec. In order to save power consumption, the transmitter is turned on just during the transmission time. The on-off keying modulation has been used to transmit the data. The data rate is up to 166 M with the average power consumption of 1.7 mW. This means that the amount of energy consumption in each pulse is 10.2 PJ/pulse. Keywords: Impulse Radio UWB transmitter, Implantable Medical Device