MPC9448 Rev 7 3/15/16

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©2016 INTEGRATED DEVICE TECHNOLOGY, INC.

MPC9448 DATASHEET

TJ,MAX should be selected according to the MTBF system

requirements, and Figure 9 Rthja can be derived from

Figure 10. The Rthja represent data based on 1S2P boards.

Using 2S2P boards will result in a lower thermal impedance

than indicated below.

If the calculated maximum frequency is below 350 MHz, it

becomes the upper clock speed limit for the given application

conditions. The following eight derating charts describe the

safe frequency operation range for the MPC9448. The charts

were calculated for a maximum tolerable die junction

temperature of 110°C (120°C), corresponding to an

estimated MTBF of 9.1 years (4 years), a supply voltage of

3.3 V and series terminated transmission line or capacitive

loading. Depending on a given set of these operating

conditions and the available device convection, a decision on

the maximum operating frequency can be made.

Figure 7. Maximum MPC9448 Frequency, VCC = 3.3 V,

MTBF 9.1 Years, Driving Series Terminated

transmission lines, 2s2p board

Figure 8. Maximum MPC9448 frequency, VCC = 3.3 V,

MTBF 9.1 Years, 4 pF Load per Line, 2s2p Board

Figure 9. No maximum Frequency Limitation for

VCC = 3.3 V, MTBF 4 Years, Driving Series

Terminated Transmission Lines, 2s2p Board

Figure 10. Maximum MPC9448 Frequency, VCC = 3.3 V,

MTBF 4 Years, 4 pF Load per Line, 2s2p Board

Table 10. Thermal Package Impedance of the 32ld LQFP

Convection, LFPM

Rthja (1P2S board),

C/W

Rthja (2P2S board),

C/W

Still air

86

61

100 lfpm

76

56

200 lfpm

71

54

300 lfpm

68

53

400 lfpm

66

52

500 lfpm

60

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