LDO regulator works from 0.5-3V

Torex Semiconductor Ltd has announced the XC6603/XC6604 series LDOs that the company said is ideal for applications that require high-efficiency and large-current output in a low voltage range. The devices are related products to the 1A high-speed XC6602 LDO regulator that is capable of operation from a low voltage of 0.5V and has low ON resistance, said the company.

With the help of a bias voltage that can be set between 2.5V and 6V, the XC6603/XC6604 operates with input voltages from 0.5-3V and is readily available with fixed output voltages from 0.5-1.8V in 0.1V steps. Thanks to its integrated N-ch driver transistor, the minimum input and output voltages of the XC6603/XC6604 can be much lower than more traditional LDOs with their integrated P-ch transistors, boasted Torex.

Another advantage of the XC6603/XC6604 integrated N-ch driver transistor is that it dramatically reduces the on-resistance at low output voltages, leading to dropout voltages as low as 162mV @ 1A with V_OUT=1.2V (V_BIAS=3.3V). This makes the XC6603/XC6604 ideally suited for low input/output voltage applications that require high output current and extended battery life, Torex said. An external 2.2?F ceramic output capacitor can be connected to obtain a stable output, added the company.

A soft-start circuit prevents rush current from V_IN to V_OUT when the IC is started and can limit voltage fluctuations on the V_IN line due to rush current. The soft-start time of the XC6604 series is set internally to 430?A (typ.), but in the XC6603 series this can be extended with an external capacitor (CSS), explained Torex.

The current limit value of the overcurrent protection circuit of each series is set internally to 1.3A (typ.), but in the XC6604 series, this can be set as needed for the required current range using an external resistor (RLIM).

Other protection functions include an overcurrent protection circuit (fold-back), thermal shutdown circuit (TSD) and an undervoltage lockout circuit (UVLO).

A small USP-6C or SOT-26W package can be selected as appropriate for the application, and this product complies with the EU RoHS directive and is Pb free.