85222AM-02

www.icst.com/products/hiperclocks.html

REV. A JANUARY 25, 2006

7

Integrated

Circuit

Systems, Inc.

ICS85222-02

PRELIMINARY

3. Calculations and Equations.

The purpose of this section is to derive the power dissipated into the load.

HSTL output driver circuit and termination are shown in Figure 1.

Ω load.

Pd_H is power dissipation when the output drives high.

Pd_L is the power dissipation when the output drives low.

Pd_H = (V

OH_MIN

/R

L

) * (V

DD_MAX

- V

OH_MIN

)

Pd_L = (V

OL_MAX

/R

L

) * (V

DD_MAX

- V

OL_MAX

)

Pd_H = (1V/50

Ω) * (3.465V - 1V) = 49.3mW

Pd_L = (0.4V/50

Ω) * (3.465V - 0.4V) = 24.52mW

Total Power Dissipation per output pair = Pd_H + Pd_L = 73.8mW

V

DD

V

OUT

RL

50

Ω

Q1