MPC8349EVVALDB datasheet(82/87 Pages) FREESCALE

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MPC8349EA PowerQUICC II Pro Integrated Host Processor Hardware Specifications, Rev. 13

Freescale Semiconductor

Ordering Information

V2 =(1 ÷ (1/R1 +1/R2)) × Isource. Solving for the output impedance gives Rsource = Rterm × (V1 ÷ V2 –1).

The drive current is then Isource =V1 ÷ Rsource.

Table 65 summarizes the signal impedance targets. The driver impedance are targeted at minimum VDD,

nominal OVDD, 105°C.

21.6

Configuration Pin Multiplexing

The MPC8349EA power-on configuration options can be set through external pull-up or pull-down

resistors of 4.7 k

Ω on certain output pins (see the customer-visible configuration pins). These pins are used

as output only pins in normal operation.

However, while HRESET is asserted, these pins are treated as inputs, and the value on these pins is latched

when PORESET deasserts. Then the input receiver is disabled and the I/O circuit takes on its normal

function. Careful board layout with stubless connections to these pull-up/pull-down resistors coupled with

the large value of the pull-up/pull-down resistor should minimize the disruption of signal quality or speed

for the output pins.

21.7

Pull-Up Resistor Requirements

The MPC8349EA requires high resistance pull-up resistors (10 k

Ω is recommended) on open-drain pins,

including I2C pins, and IPIC interrupt pins.

For more information on required pull-up resistors and the connections required for the JTAG interface,

refer to application note AN2931, “PowerQUICC Design Checklist.”

22 Ordering Information

This section presents ordering information for the device discussed in this document, and it shows an

example of how the parts are marked.

NOTE

The information in this document is accurate for revision 3.x silicon and

later (in other words, for orderable part numbers ending in A or B). For

information on revision 1.1 silicon and earlier versions, see the MPC8349E

PowerQUICC II Pro Integrated Host Processor Hardware Specifications

(Document Order No. MPC8349EEC).

Table 65. Impedance Characteristics

Impedance

Local Bus, Ethernet,

DUART, Control,

Configuration, Power

Management

PCI Signals

(Not Including PCI

Output Clocks)

PCI Output Clocks

(Including

PCI_SYNC_OUT)

DDR DRAM

Symbol

Unit

42 Target

25 Target

42 Target

20 Target

42 Target

25 Target

42 Target

20 Target

Differential

ZDIFF

Note: Nominal supply voltages. See Table 1, Tj = 105°C.

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