Motorola c18, Руководство разработчика

Страница: 24 / 82

Hardware Description
16 98-08901C63-A
3.1.2.4.1 Power Management
The power management block consists of the PM1000, which supplies most of the required regulated voltages, as well as a
separate LDO that supplies the FLASH core.
3.1.2.4.2 Digital Processing
The MSM5100 block performs all digital processing for the c18 module. This block contains the following module peripherals:
• UART1
• UART2
• R-UIM
• Keypad
• USB
• CODEC
• General-purpose A/D converter
3.1.2.5 Memory Block
The memory block consists of SRAM and Flash components. The c18 module contains 2 MB of SRAM and 8 MB of flash
memory. The module can accommodate an additional 8 MB flash, if required.
3.1.2.5.1 External Interfaces
The c18 module interfaces contain a USB transceiver, filters, an external interface connector (a 70-, 36- or 28-pin connector,
depending on the model), audio circuitry and a harness IC, which provides the interface to the serial LCD modules and additional
GPIOs.
3.2 POWER SUPPLY AND CURRENT CONSUMPTION
The c18 is designed to operate from a single voltage source. The module obtains its voltage supply via four VCC and four GND
pins (models with a 70-pin or 36-pin interface connector), or via two VCC and two GND pins (models with a 28-pin connector).
The source voltage must be between 3.6 V DC and 4.5 V DC (4.0 V nominal) on the c18 interface connector pins (across the
VCC and GND pins). To be able to function at the lowest supply voltage, it is important to compensate for any losses in the
power supply lines and user PCB. The voltage source must be capable of providing sufficient current to the module
(approximately 1 A). If additional loads are driven by the voltage source (such as backlights, LCD, and so on.), an additional
current load should be accommodated.
GND pins are used as power and signal ground pins. All signals, except audio signals, are referenced to GND. All single-ended
audio signals are referenced to AGND. See “Audio Interfaces” on page 28.