T1022NXE7MQA
| Model | T1022NXE7MQA |
| Description | 32-BIT, 1200MHz, RISC PROCESSOR, PBGA780 |
| PDF file | Total 197 pages (File size: 1M) |
| Chip Manufacturer | PHILIPS |
Hardware design considerations
the opportunity to cause noise injection from one PLL to the other is reduced. This circuit
is intended to filter noise in the PLL's resonant frequency range from a 500 kHz to 10
MHz range.
Each circuit should be placed as close as possible to the specific AV
DD
pin being
supplied to minimize noise coupled from nearby circuits. It should be possible to route
directly from the capacitors to the AV
DD
pin, which is on the periphery of the footprint,
without the inductance of vias.
This figure shows the PLL power supply filter circuit.
Where:
• R = 5 Ω ± 5%
• C1 = 10 μF ± 10%, 0603, X5R, with ESL ≤ 0.5 nH
• C2 = 1.0 μF ± 10%, 0402, X5R, with ESL ≤ 0.5 nH
NOTE
A higher capacitance value for C2 may be used to improve
the filter as long as the other C2 parameters do not change
(0402 body, X5R, ESL ≤ 0.5 nH).
NOTE
Voltage for AV
DD
is defined at the input of the PLL supply
filter and not the pin of AV
DD
.
1.8 V source
R
C1
C2
Low-ESL surface-mount capacitors
GND
AV
DD
_PLAT, AV
DD
_CGA1, AV
DD
_CGA2, AV
DD
_D1
Figure 74. PLL power supply filter circuit
The AV
DD
_SD1_PLLn signals provides power for the analog portions of the SerDes
PLL. To ensure stability of the internal clock, the power supplied to the PLL is filtered
using a circuit similar to the one shown in following
For maximum
effectiveness, the filter circuit is placed as closely as possible to the AV
DD
_SD1_PLLn
balls to ensure it filters out as much noise as possible. The ground connection should be
near the AV
DD
_SD1_PLLn balls. The 0.003-µF capacitors closest to the balls, followed
by a 4.7-µF and 47-µF capacitor, and finally the 0.33 Ω resistor to the board supply plane.
The capacitors are connected from AV
DD
_SD1_PLLn to the ground plane. Use ceramic
chip capacitors with the highest possible self-resonant frequency. All traces should be
kept short, wide, and direct.
QorIQ T1042, T1022 Data Sheet, Rev. 2, 06/2015
Freescale Semiconductor, Inc.
171
