Datasheet
LPC185X_3X_2X_1X All information provided in this document is subject to legal disclaimers. © NXP Semiconductors N.V. 2014. All rights reserved.
Product data sheet Rev. 4.1 — 6 May 2014 79 of 148
NXP Semiconductors
LPC185x/3x/2x/1x
32-bit ARM Cortex-M3 microcontroller
• Selectable time period from (T
cy(WDCLK)
256 4) to (T
cy(WDCLK)
2
24
4) in
multiples of T
cy(WDCLK)
4.
• The Watchdog Clock (WDCLK) uses the IRC as the clock source.
7.18 Analog peripherals
7.18.1 Analog-to-Digital Converter
Remark: The LPC185x/3x/2x/1x contain two 10-bit ADCs. All input channels are shared
between ADC0 and ADC1.
7.18.1.1 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.
7.18.2 Digital-to-Analog Converter (DAC)
7.18.2.1 Features
• 10-bit resolution
• Monotonic by design (resistor string architecture)
• Controllable conversion speed
• Low power consumption
7.19 Peripherals in the RTC power domain
7.19.1 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.
7.19.1.1 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.