 |
Electronic Components Datasheet Search |
|
|
Electronic Components Datasheet Search |
|
LPC2141 Datasheet(PDF) 23 Page - NXP Semiconductors |
|
||||||||||||||||||||||||||||||
LPC2141 Datasheet(HTML) 23 Page - NXP Semiconductors |
|
|
23 / 38 page  9397 750 14985 © Koninklijke Philips Electronics N.V. 2005. All rights reserved. Preliminary data sheet Rev. 01 — 3 October 2005 23 of 38 Philips Semiconductors LPC2141/42/44/46/48 Single-chip 16-bit/32-bit microcontrollers 6.19.8 Power control The LPC2141/42/44/46/48 supports two reduced power modes: Idle mode and Power-down mode. In Idle mode, execution of instructions is suspended until either a reset or interrupt occurs. Peripheral functions continue operation during Idle mode and may generate interrupts to cause the processor to resume execution. Idle mode eliminates power used by the processor itself, memory systems and related controllers, and internal buses. In Power-down mode, the oscillator is shut down and the chip receives no internal clocks. The processor state and registers, peripheral registers, and internal SRAM values are preserved throughout Power-down mode and the logic levels of chip output pins remain static. The Power-down mode can be terminated and normal operation resumed by either a reset or certain specific interrupts that are able to function without clocks. Since all dynamic operation of the chip is suspended, Power-down mode reduces chip power consumption to nearly zero. Selecting an external 32 kHz clock instead of the PCLK as a clock-source for the on-chip RTC will enable the microcontroller to have the RTC active during Power-down mode. Power-down current is increased with RTC active. However, it is significantly lower than in Idle mode. A Power Control for Peripherals feature allows individual peripherals to be turned off if they are not needed in the application, resulting in additional power savings during active and Idle mode. 6.19.9 VPB bus The VPB divider determines the relationship between the processor clock (CCLK) and the clock used by peripheral devices (PCLK). The VPB divider serves two purposes. The first is to provide peripherals with the desired PCLK via VPB bus so that they can operate at the speed chosen for the ARM processor. In order to achieve this, the VPB bus may be slowed down to 1 ⁄ 2 to 1 ⁄ 4 of the processor clock rate. Because the VPB bus must work properly at power-up (and its timing cannot be altered if it does not work since the VPB divider control registers reside on the VPB bus), the default condition at reset is for the VPB bus to run at 1 ⁄ 4 of the processor clock rate. The second purpose of the VPB divider is to allow power savings when an application does not require any peripherals to run at the full processor rate. Because the VPB divider is connected to the PLL output, the PLL remains active (if it was running) during Idle mode. 6.20 Emulation and debugging The LPC2141/42/44/46/48 support emulation and debugging via a JTAG serial port. A trace port allows tracing program execution. Debugging and trace functions are multiplexed only with GPIOs on Port 1. This means that all communication, timer and interface peripherals residing on Port 0 are available during the development and debugging phase as they are when the application is run in the embedded system itself. 6.20.1 EmbeddedICE Standard ARM EmbeddedICE logic provides on-chip debug support. The debugging of the target system requires a host computer running the debugger software and an EmbeddedICE protocol convertor. EmbeddedICE protocol convertor converts the remote debug protocol commands to the JTAG data needed to access the ARM core. |
Similar Part No. - LPC2141 |
|
Similar Description - LPC2141 |
|
|
Link URL |
| Privacy Policy |
| ALLDATASHEET.COM |
| Does ALLDATASHEET help your business so far? [ DONATE ] |
About Alldatasheet | Advertisement | Datasheet Upload | Contact us | Privacy Policy | Link Exchange | Manufacturer List All Rights Reserved©Alldatasheet.com |
| Russian : Alldatasheetru.com | Korean : Alldatasheet.co.kr | Spanish : Alldatasheet.es | French : Alldatasheet.fr | Italian : Alldatasheetit.com Portuguese : Alldatasheetpt.com | Polish : Alldatasheet.pl | Vietnamese : Alldatasheet.vn Indian : Alldatasheet.in | Mexican : Alldatasheet.com.mx | British : Alldatasheet.co.uk | New Zealand : Alldatasheet.co.nz |
|
Family Site : ic2ic.com |
icmetro.com |
English ▼
English
Chinese
German
Japanese
Russian
Korean
Spanish
French
Italian
Portuguese
Polish
Vietnamese
Indian
Mexican
British
New Zealand
