Power Dissipation Calculation (Non ODT device) | |
Pd   =  Core Power  +  I/O Switching Power | |
       =   VDD  IDD   +   α   f   CL   VDDQ2   N | |
                                                            (N - number of I/Os that are switching) |
Power Dissipation Calculation (ODT device) | |
Pd   =  Core Power  +  I/O Switching Power  +  ODT Power | |
       =   VDD  IDD   +   α   f   CL   VDDQ2   N   +   (5/16) [VDDQ2/ R ] NI/P | |
                                                (N - number of I/Os that are switching)  (NI/P - number of inputs with ODT) | |
                                                (R - R is the termination resistor divided by 2) | |
Note:   Please refer AN4017 and AN42468 for further Information and Derivation of the equations |
Explanation of how to use this calculator (User Guide) | |
To get the Power Dissipation for Non ODT device, user has to calculate Core Power followed by the I/O Switching Power. | |
To get the Power Dissipation for ODT device, user has to calculate Core Power, I/O Switching Power and ODT Power sequentially in order. | |
To calculate the Core Power Dissipation, user has to enter VDD and IDD. Then user has to press calculate button in the segment of the data entered, to obtain the Core Power Dissipation. | |
To calculate the I/O Switching Power Dissipation, user has to enter α, f, CL, VDDQ and N. Then user has to press calculate button in the segment of the data entered, to obtain the I/O Switching Power Dissipation. | |
If the device has ODT inputs then to calculate the ODT Power Dissipation, user has to enter NI/P and R. Then user has to press calculate button in the segment of the data entered, to achieve the ODT Power Dissipation. | |
To calculate the Junction Temperature for respective device, user has to enter θJA and TA. Then user has to press calculate button in the segment of the data entered, to obtain the Junction Temperature for the desired device. |
Calculation of Power Dissipation and Junction Temperature | |
Core Power Calculator | |
To calculate the IDD for desired Frequency, Please refer Active Current Calculator | |
Enter VDD | (V)  |
Enter IDD | (mA)  |
    Calculated Core Power | (mW)  |
                                                               |
I/O Switching Power Calculator | |
Enter Activity Factor, α | (0.5 for Sync, 1 for DDR/QDR)  |
Enter Clock Frequency, f | (MHz)  |
    OR Enter Access Speed | (ns)  |
Enter Load Capacitance, CL | (pf)  |
Enter Number of switching I/Os | |
Enter VDDQ | (V)  |
    Calculated I/O Switching Power | (mW)  |
                                                              |
ODT Power Calculator (for ODT device only) | |
VDDQ | (V)  |
Enter Number of ODT Inputs NI/P |   |
Enter R | (Ohm)  |
    Calculated ODT Power | (mW)  |                                                                |
Junction Temperature Calculator | |
Total Power Dissipation (Non ODT device)  (Pd) | (mW)  |
Total Power Dissipation (ODT device)  (Pd) | (mW)  |
Enter Thermal Resistance (Junction to Ambient), θJA | (ºC/W)  |
Enter Operating Temperature (Ambient Temp), TA | (ºC)  |
   Calculated Junction Temperature, TJ (Non ODT device) | (ºC)  |
   Calculated Junction Temperature, TJ (ODT device) | (ºC)  |
                                                              |
Cypress Semiconductor | |