PM5381-BI PMC-Sierra, Inc., PM5381-BI Datasheet - Page 564

• Manufacturer Part Number: PM5381-BI
• Description: ATM UNI, Single Channel ATM PHY Interface for 2488.32Mbps
• Manufacturer: PMC-Sierra, Inc.

16.2
16.3
Proprietary and Confidential to PMC-Sierra, Inc., and for its Customers’ Internal Use
Document ID: PMC-2000489, Issue 4
1. Use a single plane for both digital and analog grounds.
2. Provide separate analog transmit, analog receive, and digital supplies, but otherwise connect the
3. Ferrite beads are not advisable in digital switching circuits because inductive spiking (di/dt noise)
4. The following analog power-supply filtering is recommended:
Power Sequencing
Due to ESD protection structures in the pads it is necessary to exercise caution when powering a
device up or down. ESD protection devices behave as diodes between power supply pins and
from I/O pins to power supply pins. Under extreme conditions, incorrect power sequencing may
damage these ESD protection devices or trigger latch up.
The recommended power supply sequencing is as follows:
1. VDDO power must be supplied either before VDDI or simultaneously with VDDI.
2. AVDH can be applied either before or after VDDO, but must be applied either before or
3. AVDL must be applied after AVDH and VDDO, and either before or after VDDI. Or, AVDL
4. I/Os get driven after all the supplies have been powered. Otherwise, the I/Os must be current
5. Power down the device in the reverse sequence.
Power Supply Filtering
supply voltages together at one point close to the connector where the voltage is brought to the
card.
is introduced into the power rail. Simple RC filtering is probably the best approach provided care
is taken to ensure the IR drop in the resistance does not lower the supply voltage below the
recommended operating voltage.
Table 31 Optimal OC48 Analog Power-Supply Filtering Recommendations
Ball
Name
AVDH
AVDH
simultaneously with VDDI and AVDL. In operation, the differential voltage measured
between AVDH supplies and VDDO_DC must be less than 0.5 volt. The relative power
sequencing of the multiple AVDH power supplies is not important.
can be applied simultaneously with VDDO, AVDH, and VDDI.
limited to 20 mA.
Ball Location
AB1
AC4, AF4, AG3,
AH2 AJ1, W4,
U3, U4
Label in Figure
50
AVDH (CSU)
AVDH (TXLV)
Function
APS transmitter
power
APS CSU power
S/UNI-2488 Telecom Standard Product Datasheet
Filtering
3.3W + [100nF || 10nF]
3.3W + [1.0uF || 10nF]
(can be paired up -
maximum of 2 per filter)
Released
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