NATIONAL Semiconductor, represented in Australia by Arrow Electronics , has released seven low dropout (LDO) regulators designed to meet the power management needs of digital processor, analogue and RF subsystems.
The LDOs are optimised for cell phones, notebooks, PDAs, MP3 players and other handheld portable systems. They are also suitable for use in wireless LANs, medical equipment and industrial equipment.
The LP399x family includes products customised to meet the power needs of digital loads or RF and analogue loads in mobile and handheld devices. Their small size, low dropout voltages and low current usage during standby mode allow the creation of smaller devices with longer battery lives.
The LP3990 is a 150mA CMOS linear regulator with preset output voltages between 3.3V and 0.8V. It is optimised to meet the requirements of portable and battery-powered devices. It offers a balance between fast load transient response and low operating current. It works without a reference bypass capacitor, saving space on printed circuit boards and reducing the overall bill of materials. Packaging options are large bump micro SMD, LLP chip-scale and SOT23-5.
The LP3992 is a 30mA CMOS linear regulator designed for digital loads. It is suited to power applications such as Bluetooth baseband devices, where the controlled turn-on and turn-off times ensure the digital device does not fall into non-defined states. It is available in an SOT23-5 package.
The LP3993 is a 80mA CMOS linear regulator offering low operating current for mobile applications where fast start-up and good line and load regulation are important. An operating current of 10μA at 1mA load significantly increases standby time. The LP3993 also works without a bypass capacitor, reducing the overall PCB area and the bill of materials. Packaging options are large-bump thin, micro SMD and SOT23-5.
The LP3994 is a 50mA CMOS linear regulator designed for low operating current, low noise and accurate output voltage. The device operates in the 2.5V to 6.0V input range and has an operating current range of 20μA when enabled. When disabled the device draws virtually no current. Packaging options are large-bump, thin micro SMD and LLP chip-scale.
The LP3997 is a 250mA CMOS linear regulator that can supply up to 500mA peak output and an out-of-regulation error flag that indicates when the device's output is below the nominal voltage.
The LP3995 and LP3999 complement the existing LP3985 family by extending the output voltage range down to 1.5V. They are designed for portable and wireless applications powered by Li-Ion and Ni-MH batteries. Device noise is 25µV rms, PSRR is above 60dB at 1kHz and dropout performance is 60mV at 150mA.