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© 2016 Integrated Device Technology, Inc

July 29, 2016

813078I Data Sheet

Power Considerations

This section provides information on power dissipation and junction temperature for the ICS813078I.

Equations and example calculations are also provided.

1.

Power Dissipation.

The total power dissipation for the ICS813078I is the sum of the core power plus the power dissipated in the load(s). The following is the

power dissipation for VCC = 3.3V + 5% = 3.465V, which gives worst case results.

Core and LVPECL Output Power Dissipation

•

Power (core)_MAX = VCC_MAX *IEE_MAX = 3.465V * 260mA = 900.9mW

Power (output)_MAX = 30mW/Loaded Output Pair

If all outputs are loaded, the total power is 5 * 30mW = 150mW

LVCMOS Output Power Dissipation

•

Output Impedance ROUT Power Dissipation due to Loading 50 to VCCO/2

Output Current IOUT = VCCO_MAX / [2 * (50 + ROUT)] = 3.465V / [2 * (50 + 15)] = 26.7mA

•

Power Dissipation on the ROUT per LVCMOS output

Power (ROUT) = ROUT * (IOUT)

2 = 15

 * (26.7mA)2 = 10.7mW per output

•

Total Power Dissipation on the ROUT

Total Power (ROUT) = 10.7mW * 4 = 42.8mW

•

Dynamic Power Dissipation at 153.6MHz

Power (25MHz) = CPD * Frequency * (VCCO)

2 = 10pF * 153.6MHz * (3.465V)2 = 18mW per output

Total Power (153.6MHz) = 18mW * 4 = 72mW

Total Power Dissipation

•

Total Power

= Power (core) + Power (LVPECL output) + Total Power (ROUT) + Total Power (153.6MHz)

= 900.9mW + 150mW + 42.8mW + 72mW

= 1165.7mW