The LT3045 builds on the performance of past bulletproof  PNP and current-reference-based regulators but takes the performance level significantly higher. As shown here, the closest devices are the LT3042 (200mA, same family), the LT3085 (500mA, current based reference NPN power device), and the LT1763 (500mA, PNP power device). The “little brother” LT3042 has similar input voltage range, accuracy and protection but lower output current, with higher PSRR and higher dropout. Compared to the LT3085 which features a similar current-based reference topology, the LT3045 has narrower input voltage range, yet can operate down to zero volts output, has higher quiescent current, and slightly bigger package footprints. However, LT3045 has fast startup capability, programmable precision current limit and power good, low dropout in single supply operation, and much better PSRR and noise performance. Finally, when compared to LT1763, the LT3045 has similar input voltage range, accuracy and protection, but higher PSRR, lower noise, operation down to zero volts output and lower dropout. Note that quiescent current is not that important in low-noise applications because customers requiring low noise understand that physics dictates the need for higher quiescent current to achieve low noise performance.