LPC1850_1109 Datasheet, PDF (79/142 Pages) NXP Semiconductors – 32-bit ARM Cortex-M3 MCU; up to 200 kB SRAM; Ethernet, two High-speed USB, LCD, and external memory controller

NXP Semiconductors
LPC1850/30/20/10
32-bit ARM Cortex-M3 microcontroller
7.16.2 Digital-to-Analog Converter (DAC)
7.16.2.1 Features
• 10-bit resolution
• Integral Non-Linearity
• Differential Non-Linearity
• Monotonic by design (resistor string architecture)
• Controllable conversion speed
• Low power consumption
7.17 Peripherals in the RTC power domain
7.17.1 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 very little power when its registers are not being
accessed by the CPU, especially reduced power modes. The RTC is clocked by a
separate 32 kHz oscillator that produces a 1 Hz internal time reference and is powered by
its own power supply pin, VBAT.
7.17.1.1 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. Less than <tbd> required
for battery operation. 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.
• Alarm interrupt can be generated for a specific date/time.
7.17.2 Alarm timer
The alarm timer is a 16-bit timer and counts down at 1 kHz from a preset value generating
alarms in intervals of up to 1 min. The counter triggers a status bit when it reaches 0x00
and asserts an interrupt if enabled.
The alarm timer is part of the RTC power domain and can be battery powered.
7.18 System control
7.18.1 Configuration registers (CREG)
The following settings are controlled in the configuration register block:
• BOD trip settings
• Oscillator output
• DMA-to-peripheral muxing
LPC1850_30_20_10
Preliminary data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 2.2 — 9 September 2011
© NXP B.V. 2011. All rights reserved.
79 of 142