15 of 32 June 2, 2015
IDT 89HPES16T4AG2 Data Sheet
Power Consumption
Typical power is measured under the following conditions: 25°C Ambient, 35% total link usage on all ports, typical voltages defined in Table 12
(and also listed below).
Maximum power is measured under the following conditions: 70°C Ambient, 85% total link usage on all ports, maximum voltages defined in
Table 12 (and also listed below).
Thermal Considerations
This section describes thermal considerations for the PES16T4AG2 (19mm
2
FCBGA324 package). The data in Table 16 below contains informa-
tion that is relevant to the thermal performance of the PES16T4AG2 switch.
Note: It is important for the reliability of this device in any user environment that the junction temperature not exceed the T
J(max)
value
specified in Table 16. Consequently, the effective junction to ambient thermal resistance (
θ
JA
) for the worst case scenario must be
maintained below the value determined by the formula:
θ
JA
= (T
J(max)
- T
A(max)
)/P
Given that the values of T
J(max)
, T
A(max)
, and P are known, the value of desired θ
JA
becomes a known entity to the system designer. How to
achieve the desired
θ
JA
is left up to the board or system designer, but in general, it can be achieved by adding the effects of θ
JC
(value
provided in Table 16), thermal resistance of the chosen adhesive (
θ
CS
), that of the heat sink (θ
SA
), amount of airflow, and properties of the
circuit board (number of layers and size of the board). As a general guideline, this device will not need a heat sink if the board has 8 or more
layers AND the board size is larger than 4”x12” AND airflow in excess of 0.5 m/s is available. It is strongly recommended that users perform
their own thermal analysis for their own board and system design scenarios.
Number of active
Lanes per Port
Core Supply
PCIe Analog
Supply
PCIe Analog
High Supply
PCIe Termin-
ation Supply
I/O Supply Total
Typ
1.0V
Max
1.1V
Typ
1.0V
Max
1.1V
Typ
2.5V
Max
2.75V
Typ
1.0V
Max
1.1V
Typ
3.3V
Max
3.465V
Typ
Power
Max
Power
8/4/4 mA 413 905 901 963 110 123 360 429 2 2
Watts 0.41 1.0 0.90 1.06 0.28 0.34 0.36 0.47 0.007 0.007 1.96 2.87
4/4/4/4 mA 413 905 901 963 110 123 180 215 2 2
Watts 0.41 1.0 0.90 1.06 0.28 0.34 0.18 0.24 0.01 0.01 1.78 2.64
Table 15 PES16T4AG2 Power Consumption
Symbol Parameter Value Units Conditions
T
J(max)
Junction Temperature 125
o
CMaximum
T
A(max)
Ambient Temperature 70
o
CMaximum
θ
JA(effective)
Effective Thermal Resistance, Junction-to-Ambient
16.8
o
C/W Zero air flow
10.1
o
C/W 1 m/S air flow
9.2
o
C/W 2 m/S air flow
θ
JB
Thermal Resistance, Junction-to-Board 4.1
o
C/W
θ
JC
Thermal Resistance, Junction-to-Case 0.3
o
C/W
P Power Dissipation of the Device 2.87 Watts Maximum
Table 16 Thermal Specifications for PES16T4AG2, 19x19 mm FCBGA324 Package
