In hand-held device applications where the input voltage may be higher or lower than the output voltage, buck-boost regulators are claimed to improve efficiency and provide longer battery life compared to a boost regulator plus bypass solution.
The ISL91127 and ISL91128 operate in buck, boost or buck-boost mod. The regulators’ input voltage, ranging from 1.8 to 5.5V, supports multiple battery topologies and their output voltage, ranging from 1V to 5.2V, is combined with an output current of 3A.
The output voltage of the ISL91128 can be adjusted dynamically using the I2C interface. This eliminates feedback resistors and allows the reuse of the same design for multiple output voltage needs.
| Key features: • 30uA typical quiescent current • Up to 96% efficiency (PVIN = 3.6V, Vout = 3.4 to 4V, Iout = 200mA) • Output current up to 3A in boost mode (PVIN = 3V, Vout = 3.3V) • Input voltage ranging from 1.8 to 5.5V, output voltage; 3.3V • Full protection for under-voltage, short-circuit, and thermal faults |
