The TPS6210x family of low-power high-efficiency buck converters is designed to operate from 1 or 2 li-ion cell battery packs. This part, with its wide input range of 2.5 V to 9 V, has an adjustable output from 0.8 V to 8 V and is capable of 500-mA output current. The TPS6210x family of synchronizable dc-to-dc converters is available in four different operating frequencies: 300 kHz, 600 kHz, 1 MHz, and 2 MHz. The circuit can be allowed to run at a fixed frequency, or sychronized, using the dual function SD/SYNC input pin. The TPS6210x family is highly efficient at both low and high output currents. The tri-function MODE input pin is used to select constant-frequency, auto-mode, or light-load modes of operation. The multimode operation allows the IC to select the most efficient operating mode, or if desirable, the user can determine which of three modes to operate in. In the auto-mode, the output load detector circuitry determines if the converter should be running in the constant-frequency, heavy-load mode, or pulsed-variable frequency, light-load mode. The TPS6210x family also has a shutdown mode for optimum battery shelf life. The IC utilizes three methods of overload protection, including thermal shutdown and two levels of overcurrent protection. The TPS6210x is available in the small outline 8-pin SOIC package.