Altera MAX V CPLD - Manual (Page 19)

Chapter 5: Board Test System 5–5
Using the Board Test System
January 2011 Altera Corporation MAX V CPLD Development Kit User Guide
Power Consumption Calculations
To calculate the estimated power consumption of the 1.8 VCCINT core power, the
Power
tab uses the following formulas to arrive at the results after clicking Calculate:
■ Current across Rsense (R44) = Voltage drop across Rsense/Rsense resistance
■ Power consumption of V
CCINT
= device core voltage (V
CCINT
) × current across
Rsense
For example:
Current across Rsense (R44) = (0.756 mV)/(0.27) = 2.8 mA
Power consumption of V
CCINT
= (1.8 V) × (2.8 mA) = 5.04 mW
You can apply the same formulas to the VARIABLE VCCIO power estimation
calculation:
Current across Rsense (R47) = (0.332 mV)/(0.27) = 1.23 mA
Power consumption of V
CCIO
= (3.3 V) × (1.23 mA) = 4.06 mW
Power Tab Controls
The following sections describe the controls on the Power tab.
1.8 VCCINT
■ TP1-TP2 —Allows you to enter the value recorded from the multimeter.
■ Result —Shows the calculated power consumption after clicking Calculate.
■ Calculate —Perfoms calculation for estimated power consumption.
VARIABLE VCCIO
■ TP3-TP4 —Allows you to enter the value recorded from the multimeter.
■ VAR VCCIO —Allows you to select the voltage level that matches the current
setting on J8 on the development board.
■ Result —Shows the calculated power consumption after clicking Calculate.
■ Calculate —Perfoms calculation for estimated power consumption.