New NXP Cortex-M0 microcontroller features UVLO for power control and power monitoring applications

March 27, 2012 // By Paul Buckley
NXP Semiconductors N.V. has unveiled the LPC11A00 microcontroller series featuring a flexible analog subsystem, based on the ARM Cortex-M0 processor. Combining 50-MHz CPU performance with advanced analog features including Undervoltage Lockout (UVLO) in a 2.5 x 2.5-mm WLCSP package.

The LPC11A00 is an ideal replacement for 8/16-bit microcontrollers in a variety of power management applications, which present significant challenges in terms of overall system performance, space constraints, and harsh environments. Fully integrated with an on-chip temperature sensor and up to 4 KB of EEPROM, the LPC11A00 microcontroller is well-suited for uninterrupted power supplies (UPS), power inverters, intelligent battery chargers, power factor correction, sensors, lighting, and power-conversion applications.

The integrated UVLO feature eliminates the need for external components and allows the microcontroller to remain in a safe system state whenever the supply voltage level is below the minimum valid operating level of 2.4 V. This feature supports various kinds of power supply ramps including cold power-up, power droop, and power-down ramps, making the LPC11A00 extremely useful in power control and monitoring applications.

The analog subsystem in the LPC11A00 microcontroller includes UVLO protection against power-supply drops below 2.4V; on-chip comparator with programmable voltage reference; 10-bit ADC with input multiplexing among 8 pins; 10-bit DAC with flexible conversion triggering; an integrated temperature sensor; and a highly accurate 0.9 voltage reference which can be used for internal ADC calibration. By providing seamless integration of the various analog blocks, the LPC11A00 allows system designers to off-load critical tasks from the CPU.

The interconnected subsystem offers flexible operation allowing the comparator to trigger ADC and DAC operations while taking timestamps from a 32-bit or a 16-bit timer. Conversely, these analog operations can also be triggered by the timers. For efficient system monitoring, the comparator and the timers can be further configured to make time measurements of fluctuating analog signals.

Ideal for small form factor power applications, the 20-pin WLCSP 2.5 x 2.5-mm package enables debugging/programming via the I 2 C-bus – a unique feature which minimizes the number of pins for system integration while simplifying board layout. On-chip ROM-based routines for the I 2 C interface enable seamless integration via an easy-to-use API-driven interface. The