LDO Regulators Target Portable Apps

Packaged in an 8-pin 2- by 2-mm TDFN, the MAX8902A and MAX8902B are the industry’s smallest 500-mA, low-noise, low-dropout linear regulators. The devices provide up to 92 dB power-supply ripple rejection (PSRR) at 5 kHz, 16 µV rms output noise, and a 100-mV (maximum) dropout voltage at full load (500 mA). This performance makes the regulators well suited for use in noise-sensitive and space-constrained applications like smart phones, PDAs, PMP/MP3 players, GPS devices, and ultra-mobile/notebook PCs. The input voltage range is 1.7 to 5.5 V, and output voltage accuracy is ±1.5%. The MAX8902A features preset pin-selectable output voltages between 1.5 and 4.7 V, and the MAX8902B allows users to adjust the output voltage between 0.6 and 5.3 V using two external resistors. To maximize battery life, the devices consume only 80 µA operating current and less than 1 µA shutdown current. Other features include a programmable soft-start circuit to prevent high inrush currents, short-circuit protection, reverse-current protection, and thermal shutdown. The thermally enhanced package allows the regulators to be fully specified over the –40°C to 125°C automotive temperature range. Prices start at $1.25 in quantities of 1000. MAXIM INTEGRATED PRODUCTS, Sunnyvale, CA. (408) 737-7600.