Datasheet

LPC82x All information provided in this document is subject to legal disclaimers. © NXP Semiconductors N.V. 2014. All rights reserved.
Product data sheet Rev. 1 — 1 October 2014 22 of 81
NXP Semiconductors
LPC82x
32-bit ARM Cortex-M0+ microcontroller
• The WKT can be used for waking up the part from any reduced power mode,
including Deep power-down mode, or for general-purpose timing.
8.20 Analog comparator (ACMP)
The analog comparator with selectable hysteresis can compare voltage levels on external
pins and internal voltages.
After power-up and after switching the input channels of the comparator, the output of the
voltage ladder must be allowed to settle to its stable value before it can be used as a
comparator reference input. Settling times are given in Table 24
.
The analog comparator output is a movable function and is assigned to a pin through the
switch matrix. The comparator inputs and the voltage reference are enabled through the
switch matrix.
8.20.1 Features
• Selectable 0 mV, 10 mV ( 5 mV), and 20 mV ( 10 mV), 40 mV ( 20 mV) input
hysteresis.
• Two selectable external voltages (V
DD
or VDDCMP on pin PIO0_6); fully configurable
on either positive or negative input channel.
• Internal voltage reference from band gap selectable on either positive or negative
input channel.
• 32-stage voltage ladder with the internal reference voltage selectable on either the
positive or the negative input channel.
Fig 8. Comparator block diagram
4
32
4
ACMP_I[4:1]
V
DD
VDDCMP
ADC_0
internal
voltage
reference
edge detect
sync
comparator
level ACMP_O,
ADC trigger
comparator
edge NVIC
COMPARATOR ANALOG BLOCK COMPARATOR DIGITAL BLOCK
aaa-012135