PCI6621 datasheet(49/204 Pages) TI

49 / 204 page

3−1

3 Feature/Protocol Descriptions

The following sections give an overview of the PCI6x21/PCI6x11 controller. Figure 3−1 shows the connections to the

PCI6x21/PCI6x11 controller. The PCI interface includes all address/data and control signals for PCI protocol. The

interrupt interface includes terminals for parallel PCI, parallel ISA, and serialized PCI and ISA signaling.

PCI Bus

PCI6x21/

PCI6x11

EEPROM

Power Switch

SD/MMC

Card/

UltraMedia

Card

Power

Switch

Card/

UltraMedia

Card

Power Switch

SD/MMC

MS/MSPRO

SM/xD

Figure 3−1. PCI6x21/PCI6x11 System Block Diagram

3.1

Power Supply Sequencing

The PCI6x21/PCI6x11 controller contains 3.3-V I/O buffers with 5-V tolerance requiring a core power supply and

clamp voltages. The core power supply is always 1.5 V. The clamp voltages can be either 3.3 V or 5 V, depending

on the interface. The following power-up and power-down sequences are recommended.

The power-up sequence is:

Power core 1.5 V.

Apply the I/O voltage.

Apply the analog voltage.

Apply the clamp voltage.

The power-down sequence is:

Remove the clamp voltage.

Remove the analog voltage.

Remove the I/O voltage.

Remove power from the core.

NOTE: If the voltage regulator is enabled, then steps 2, 3, and 4 of the power-up sequence

and steps 1, 2, and 3 of the power-down sequence all occur simultaneously.

PCI6621 Datasheet(PDF) 49 Page - Texas Instruments