MC145572PB Freescale Semiconductor, MC145572PB Datasheet - Page 26

• Manufacturer Part Number: MC145572PB
• Manufacturer: Freescale Semiconductor

Specifications of MC145572PB

• Number Of Line Interfaces: 1
• Control Interface: HDLC
• Lead Free Status / Rohs Status: Not Compliant

3–4
3.3.1
3.3
PIN DESCRIPTIONS
The following descriptions are divided into the same functional groups as the Pin Description Quick
Reference Tables in Section 3.2 and provide more information about the particular subsystem of the
device and the associated pins. Refer to Figures 11–1 and 11–2 for pin assignments.
Power Supply Pins
The MC145572 has five pairs of V DD and V SS power supply pins. Each of these pairs provide power
to a specific portion of the integrated circuit to minimize interaction between the various high per-
formance subsystems on the device. All of the negative power supply pins should be connected to
the same ground reference point and all of the positive power supply pins should be connected to
the same + 5 V power supply source.
XTAL in , XTAL out
V DD : Positive Power Supply
This is one of the five positive power supply pins and should be connected to + 5 V. V DD
provides power to the internal digital circuits of the device and should be decoupled with a
0.1 F ceramic capacitor to V SS .
V SS : Negative Power Supply
Two of the six negative power supply pins are V SS , and they should be connected to ground.
These pins provide a ground reference to the internal digital circuits of the device and each
should be decoupled with separate 0.1 F ceramic capacitors to V DD .
V DD Rx, V DD Tx: Positive Analog Power Supply
Two of the five positive power supply pins are V DD Rx and V DD Tx, and they should be con-
nected to + 5 V. These pins provide power to the analog receive and transmit subsystems
of the MC145572, and each should be decoupled with separate 0.1 F ceramic capacitors
to V SS Rx and V SS Tx, respectively. These two pins are not tied together internally.
V ref P, V ref N
FREQREF
Pin Name
Pin Name
RxP, RxN
TxP, TxN
See Appendix C for printed circuit board layout recommendations.
Table 3–5. Phase Locked Loop and Clock Pins (See Section 3.3.6)
Freescale Semiconductor, Inc.
For More Information On This Product,
36, 39
32, 33
35, 34
16, 15
TQFP
TQFP
25
Table 3–4. 2B1Q Interface Pins (See Section 3.3.5)
Pin No.
Pin No.
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PLCC
PLCC
33, 32
9, 12
5, 6
8, 7
42
MC145572
Positive and negative outputs of the differential transmit driver.
Positive and negative inputs to the differential receive circuit.
Positive and negative signals for internal voltage reference.
Connect a 0.1 F to 1 F ceramic capacitor between V ref P and V ref N
LT mode: 8 kHz reference clock input (Schmitt trigger input).
NT mode: optional synchronized clock output, selected by control register in
the MCU mode (MCU/GCI = 1).
Input and output signals of the 20.48 MHz crystal oscillator amplifier.
NOTE
Pin Description
Pin Description
MOTOROLA