Datasheet

Product data sheet Rev. 4 — 19 August 2014 82 of 158

NXP Semiconductors

LPC435x/3x/2x/1x

32-bit ARM Cortex-M4/M0 microcontroller

7.21 Analog peripherals

7.21.1 Analog-to-Digital Converter (ADC0/1)

Remark: The LPC435x/3x/2x/1x contain two 10-bit ADCs.

7.21.1.1 Features

• 10-bit successive approximation analog to digital converter.

• Input multiplexing among 8 pins.

• Power-down mode.

• Measurement range 0 to VDDA.

• Sampling frequency up to 400 kSamples/s.

• Burst conversion mode for single or multiple inputs.

• Optional conversion on transition on ADCTRIG0 or ADCTRIG1 pins, combined timer

outputs 8 or 15, or the PWM output MCOA2.

• Individual result registers for each A/D channel to reduce interrupt overhead.

• DMA support.

7.21.2 Digital-to-Analog Converter (DAC)

7.21.2.1 Features

• 10-bit resolution

• Monotonic by design (resistor string architecture)

• Controllable conversion speed

• Low power consumption

7.22 Peripherals in the RTC power domain

7.22.1 RTC

The Real Time Clock (RTC) is a set of counters for measuring time when system power is

on, and optionally when it is off. It uses little power when the CPU does not access its

registers, especially in the reduced power modes. A separate 32 kHz oscillator clocks the

RTC. The oscillator produces a 1 Hz internal time reference and is powered by its own

power supply pin, VBAT.

7.22.1.1 Features

• Measures the passage of time to maintain a calendar and clock. Provides seconds,

minutes, hours, day of month, month, year, day of week, and day of year.

• Ultra-low power design to support battery powered systems. Uses power from the

CPU power supply when it is present.

• Dedicated battery power supply pin.

• RTC power supply is isolated from the rest of the chip.

• Calibration counter allows adjustment to better than 1 sec/day with 1 sec resolution.

• Periodic interrupts can be generated from increments of any field of the time registers.