High voltage, low dropout linear regulators

Linear Technology has announced new wider temperature range versions of its LT1763, LT3008 and LT3010 high voltage linear regulators. The new high reliability MP grade features operation from -55 to 125°C for a range of applications including avionics, military, industrial, automotive, rf and telecom.

The LT1763, pictured, is a 500mA LDO featuring less than 20µVRMS output noise over a 10Hz to 100kHz bandwidth using a 0.01µF bypass capacitor. Supply current is 30µA and is reduced to less than 0.5µA in shutdown mode, virtually eliminating battery drain. The device operates from a 1.8 to 20V input supply, providing compatibility with a wide variety of input power sources, and its output voltage is adjustable between 1.22V and 20V. The LT1763 can also operate with capacitors as small as 3.3µF and is stable using any capacitor type, including ceramic, tantalum, or aluminum electrolytic. The device's internal protection circuitry includes reverse-battery protection, no reverse current, current limiting and thermal limiting. The LT3008 is a 20mA LDO with ultra-low quiescent current of only 3µA. It features high input voltage capability, spanning 2.0V to 45V with an adjustable output voltage ranging from 0.6V to 36V, in addition to fixed output voltage versions of 1.2V, 1.5V, 1.8V, 2.5V, 3.3V and 5V. The device delivers low dropout voltage of only 300mV. Output tolerance is tightly regulated to within ±2% over line, load and temperature. The LT3008 regulator optimizes stability and transient response with low ESR, ceramic output capacitors as small as 2.2µF. These tiny external capacitors can be used without series resistance, commonly required with alternative regulators. The IC's internal protection circuitry includes reverse-battery protection, reverse output and reverse current protection, current limiting and thermal limiting. The LT3010 is a high voltage micropower, low dropout regulator that can deliver up to 50mA of continuous output current. The device operates at input voltages from 3 to 80V, delivering output voltages as low as 1.275V. The LT3010-5 provides a fixed 5V output. Low quiescent current of 30µA (operating) and 1µA (in shutdown), also make it a suitable choice for battery powered 'keep alive' systems that require optimum run time. For high voltage applications that require large input-to-output voltage differentials, the LT3010/-5 offers a compact solution. Its thermally enhanced MSOP-8 package offers thermal resistance equivalent to much larger conventional packages. Internal protection circuitry includes reverse-battery protection, current limiting, thermal limiting, and reverse current protection.