LPC2468FBD208,551 NXP Semiconductors, LPC2468FBD208,551 Datasheet - Page 658

• Manufacturer Part Number: LPC2468FBD208,551
• Description: IC ARM7 MCU FLASH 512K 208-LQFP
• Manufacturer: NXP Semiconductors
• Series: LPC2400r

Specifications of LPC2468FBD208,551

• Program Memory Type: FLASH
• Program Memory Size: 512KB (512K x 8)
• Package / Case: 208-LQFP
• Core Processor: ARM7
• Core Size: 16/32-Bit
• Speed: 72MHz
• Connectivity: CAN, EBI/EMI, Ethernet, I²C, Microwire, MMC, SPI, SSI, SSP, UART/USART, USB OTG
• Peripherals: Brown-out Detect/Reset, DMA, I²S, POR, PWM, WDT
• Number Of I /o: 160
• Ram Size: 98K x 8
• Voltage - Supply (vcc/vdd): 3 V ~ 3.6 V
• Data Converters: A/D 8x10b; D/A 1x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Processor Series: LPC24
• Core: ARM7TDMI-S
• Data Bus Width: 16 bit, 32 bit
• Data Ram Size: 98 KB
• Interface Type: CAN/I2S/ISP/SSP/UART/USB
• Maximum Clock Frequency: 72 MHz
• Number Of Programmable I/os: 160
• Number Of Timers: 6
• Operating Supply Voltage: 3.3 V
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• 3rd Party Development Tools: MDK-ARM, RL-ARM, ULINK2, IRD-LPC2468-DEV, SAB-TFBGA208, KSK-LPC2468-PL
• Development Tools By Supplier: OM10100
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 8-ch x 10-bit
• On-chip Dac: 1-ch x 10-bit
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With: 622-1025 - KIT DEV IND REF DESIGN LPC2468622-1024 - BOARD SCKT ADAPTER FOR TFBGA208568-4358 - DISPLAY QVGA TFT FOR OM10100568-4309 - BOARD EXTENSION LPCSTICK568-4308 - EVAL LPC-STICK WITH LPC2468MCB2400U - BOARD EVAL MCB2400 + ULINK2MCB2400 - BOARD EVAL FOR NXP LPC246X SER622-1005 - USB IN-CIRCUIT PROG ARM7 LPC2K
• Eeprom Size: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant
• Other names: 568-4261; 935282457551; LPC2468FBD208-S

NXP Semiconductors
UM10237_4
User manual
6.7.5 Prescaler operation
pulses, this "jitter" could possibly be of concern in an application that wishes to observe
the contents of the Clock Tick Counter (CTC)
Counter Register (CTCR - 0xE002 4004)” on page
The Prescaler block labelled "Combination Logic" in
decrement of the 13 bit PREINT counter is extended by one PCLK. In order to both insert
the correct number of longer cycles, and to distribute them evenly, the combinatorial Logic
associates each bit in PREFRAC with a combination in the 15 bit Fraction Counter. These
associations are shown in the following
For example, if PREFRAC bit 14 is a one (representing the fraction 1/2), then half of the
cycles counted by the 13 bit counter need to be longer. When there is a 1 in the LSB of the
Fraction Counter, the logic causes every alternate count (whenever the LSB of the
Fraction Counter=1) to be extended by one PCLK, evenly distributing the pulse widths.
Similarly, a one in PREFRAC bit 13 (representing the fraction 1/4) will cause every fourth
cycle (whenever the two LSBs of the Fraction Counter = 10) counted by the 13 bit counter
to be longer.
Fig 135. RTC prescaler block diagram
CLK
13 BIT INTEGER COUNTER
13 BIT RELOAD INTEGER
(DOWN COUNTER)
REGISTER
(PREINT)
UNDERFLOW
RELOAD
13
13
Rev. 04 — 26 August 2009
Chapter 26: LPC24XX Real-Time Clock (RTC) and battery RAM
Table
APB bus
extend
reload
directly(Section 26–6.2.2 “Clock Tick
26–582.
651).
to clock tick counter
Figure 26–135
15 BIT FRACTION COUNTER
15 BIT FRACTION REGISTER
COMBINATORIAL LOGIC
(PREFRAC)
15
15
15
determines when the
UM10237
© NXP B.V. 2009. All rights reserved.
CLK
(APB clock)
PCLK
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