If you've ever tried to find an appropriate LDO for your project you may have noticed the incredibly vast range available on the market.

During my searches, I discovered this particular regulator from a company I've never heard of called ABLIC (formerly SII Semiconductor - subsidiary of Seiko Instruments).

The fixed 3.3V B-series variant claims to take an input from 1.5 to 5.5 and source up to 1A of current with 1900mW of heat dissipation in their HSOP6 package (when board mounted). The best part is the Vdrop is only 70mV at 300mA. It also has an Iq when off of 1uA. It also comes in a smaller SOT-89 package with half the heat dissipation characteristics.

As far as I can tell the performance characteristics of this LDO are head and shoulders above competitors such as Microchip, ST and even most of TI. So my question is: Why aren't more people using this chip? Am I overlooking a critical property? Why aren't competitors offering similar options in this dropout range?

A typical example is the MCP1825 from Microchip. This chip offers similar input range, output voltage but the dropout is 210mV at 500mA. LDOs like those used in ESP boards aren't even in the same ballpark with dropouts > 1V (AMS1117).

For the context of this project, this LDO will be feeding on a LiPo with an average load of 250mA and additional transient of 300mA from time to time. Until now I've been using a combination PMIC charger/buck-boost from TI which caps out at 300mA which is no longer sufficient so I've decided to run with a discrete LDO and charger IC (currently looking at the MCP73830 for anyone interested).

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    \$\begingroup\$ The TPS74301 has a dropout of 70mV@1.5A with superior line, load regulation, and PSRR. I also suspect that noise may be high with your part since it's not a listed specification so I can't even compare. The ADP1706/1707/1708 offers similar dropout voltages and currents as well. \$\endgroup\$ – Toor Apr 22 at 5:31

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