DK-35TS-LPC2478 Future Designs Inc, DK-35TS-LPC2478 Datasheet - Page 6

• Manufacturer Part Number: DK-35TS-LPC2478
• Description: PROGRAMMERS, DEVELOPMENT SYSTEMS
• Manufacturer: Future Designs Inc

Specifications of DK-35TS-LPC2478

• Sensor Type: Touch Screen
• Interface: I²C
• Voltage - Supply: 5V
• Embedded: Yes, MCU, 16/32-Bit
• Utilized Ic / Part: LPC2478 ARM7
• For Use With: 568-4742 - MODULE DIMM LPC2478 ARM7
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Sensitivity: -
• Sensing Range: -
• Other names: 622-1034; ARM-35TS-LPC2478

NXP Semiconductors
ES_LPC2478
Errata sheet
Fig 1.
A/D control register options
3.3 ADC.1: External sync inputs not operational
Introduction:
In software-controlled mode (BURST bit is 0), the 10-bit ADC can start conversion by
using the following options in the A/D Control Register:
Problem:
The external start conversion feature, AD0CR:START = 0x2 or 0x3, may not work reliably
and ADC external trigger edges on P2.10 or P1.27 may be missed. The occurrence of this
problem is peripheral clock (pclk) dependent. The probability of error (missing a ADC
trigger from GPIO) is estimated as follows:
The probability of error is not affected by the frequency of ADC start conversion edges.
Work-around:
In software-controlled mode (BURST bit is 0), the START conversion options (bits 26:24
set to 0x1 or 0x4 or 0x5 or 0x6 or 0x7) can be used. The user can also start a conversion
by connecting an external trigger signal to a capture input pin (CAPx) from a Timer
peripheral to generate an interrupt. The timer interrupt routine can then start the ADC
conversion by setting the START bits (26:24) to 0x1. The trigger can also be generated
from a timer match register.
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•
•
For PCLK_ADC = 72 MHz, probability error = 12 %
For PCLK_ADC = 50 MHz, probability error = 6 %
For PCLK_ADC = 12 MHz, probability error = 1.5 %
All information provided in this document is subject to legal disclaimers.
Rev. 6 — 1 March 2011
ES_LPC2478
Errata sheet LPC2478
© NXP B.V. 2011. All rights reserved.
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