Dolphin Integration announces an embedded high rejection LDO powering sensitive Analog Components

April, 15, 2008 -- Dolphin Integration launches an Ultra-Low Drop-Out Regulator dedicated to the supply of sensitive analog blocks: LR-2.8~4.2/1.8~3.3. Linear Regulators need to be embedded for Portable devices commonly using Lithium-Ion batteries as power source with a main challenge: maintaining the best voltage regulation over the longest battery discharge cycle, explains CIO Jean-François Pollet.  The LR-2.8~4.2/1.8~3.3 was inspired by a simple observation: mixed-signal SoCs embed even more analog  circuits like audio amplifiers with a high SNR, RF and baseband receivers, which are particularly sensitive to the cleanliness of their power supply. In systems like smart-phone and other wireless portable devices, the performances of these analog circuits is jeopardized by the violent changes on input voltage created by the GSM waves. The LR-2.8~4.2/1.8~3.3 is able to absorb voltage drops down to 300 mV on the whole operating range of a Li-Ion battery. Its resilience to such blast waves makes it the perfect shelter to supply analog blocks with a perfectly regulated output voltage.
The LR-2.8~4.2/1.8~3.3 keeps on regulating after other LDOs have quit!

As the input voltage covers the 2.6 V - 4.2 V range, maximizing the use of Li-Ion battery charge, the output voltage, digitally programmable from 1.8 V to 3.3 V, provides the voltage level required by most analog circuits embedded in CMOS SOCs. In order to guarantee reliability under 4.2 V input, the LR-2.8~4.2/1.8~3.3 is also equipped with an internal protection circuitry which prevents all transistors to be exposed to more than 3.6 V at all times.