LPC2420FBD208-S NXP Semiconductors, LPC2420FBD208-S Datasheet - Page 70

• Manufacturer Part Number: LPC2420FBD208-S
• Description: MCU 16-Bit/32-Bit LPC2000 ARM7TDMI-S RISC ROMLess 3.3V 208-Pin LQFP Tray
• Manufacturer: NXP Semiconductors

Specifications of LPC2420FBD208-S

• Package: 208LQFP
• Device Core: ARM7TDMI-S
• Family Name: LPC2000
• Maximum Speed: 72 MHz
• Ram Size: 82 KB
• Operating Supply Voltage: 3.3 V
• Data Bus Width: 16|32 Bit
• Program Memory Type: ROMLess
• Number Of Programmable I/os: 160
• Interface Type: I2C/I2S/SPI/SSP/UART/USB
• On-chip Adc: 8-chx10-bit
• On-chip Dac: 1-chx10-bit
• Operating Temperature: -40 to 85 °C
• Number Of Timers: 4

NXP Semiconductors
LPC2420_60_5
Preliminary data sheet
Fig 26. Booting from two 8-bit memory chips
13.3 XTAL and RTC Printed Circuit Board (PCB) layout guidelines
13.4 Suggested boot memory interface solutions
A[a_b:1]
The crystal should be connected on the PCB as close as possible to the oscillator input
and output pins of the chip. Take care that the load capacitors C
case of third overtone crystal usage, have a common ground plane. The external
components must also be connected to the ground plain. Loops must be made as small
as possible, in order to keep the noise coupled in via the PCB as small as possible. Also
parasitics should stay as small as possible. Values of C
smaller accordingly to the increase in parasitics of the PCB layout.
‘a_m’ and ‘a_b’ in the following figures refer to the highest order address line of the
memory chip and the highest order microcontroller’s address line used respectively.
CS1
Fig 25. Slave mode operation of the on-chip oscillator
OE
D[15:8]
BLS1
A[a_m:0]
IO[7:0]
WE
OE
CE
Rev. 05 — 24 February 2010
MEMORY
8-bit
XTAL1
LPC2xxx
C i
100 pF
D[7:0]
BLS0
002aae718
Flashless 16-bit/32-bit microcontroller
C g
A[a_m:0]
IO[7:0]
WE
CE
OE
x1
and C
LPC2420/2460
MEMORY
8-bit
002aad322
x2
x1
should be chosen
and C
© NXP B.V. 2010. All rights reserved.
x2
, and C
x3
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