LPC546xx
NXP Semiconductors
32-bit ARM Cortex-M4 microcontroller
7.21 CRC engine
The Cyclic Redundancy Check (CRC) generator with programmable polynomial settings
supports several CRC standards commonly used. To save system power and bus
bandwidth, the CRC engine supports DMA transfers.
7.21.1 Features
• Supports three common polynomials CRC-CCITT, CRC-16, and CRC-32.
– CRC-CCITT: x16 + x12 + x5 + 1
– CRC-16: x16 + x15 + x2 + 1
– CRC-32: x32 + x26 + x23 + x22 + x16 + x12 + x11 + x10 + x8 + x7 + x5 + x4 + x2 + x + 1
• Bit order reverse and 1’s complement programmable setting for input data and CRC
sum.
• Programmable seed number setting.
• Supports CPU PIO or DMA back-to-back transfer.
• Accept any size of data width per write: 8, 16 or 32-bit.
– 8-bit write: 1-cycle operation.
– 16-bit write: 2-cycle operation (8-bit x 2-cycle).
– 32-bit write: 4-cycle operation (8-bit x 4-cycle).
7.22 Temperature sensor
The temperature sensor transducer uses an intrinsic pn-junction diode reference and
outputs a CTAT voltage (Complement To Absolute Temperature). The output voltage
varies inversely with device temperature with an absolute accuracy of better than ±5 C
over the full temperature range (40 C to +105 C). The temperature sensor is only
approximately linear with a slight curvature. The output voltage is measured over different
ranges of temperatures and fit with linear-least-square lines.
After power-up, the temperature sensor output must be allowed to settle to its stable value
before it can be used as an accurate ADC input.
For an accurate measurement of the temperature sensor by the ADC, the ADC must be
configured in single-channel burst mode. The last value of a nine-conversion (or more)
burst provides an accurate result.
7.23 Security features
The OTP memory contains a memory bank of 128 bits each. OTP bank contains 4 words:
word 0 for ECRP, word 1 is reserved, words 2 and 3 can be used by user application for
storing application specific options.
7.23.1 Features
• OTP memory.
• Random number generator (RNG).
LPC546xx
All information provided in this document is subject to legal disclaimers.
© NXP Semiconductors N.V. 2018. All rights reserved.
Product data sheet
Rev. 2.5 — 20 June 2018
81 of 169
NXP [ NXP ]
