uPSD3234A, uPSD3234BV, uPSD3233B, uPSD3233BV
Table 107. PSD Module Example, Typ. Power Calculation at V
CC
= 5.0V (Turbo Mode Off)
Conditions
MCU Clock Frequency
Highest Composite PLD input frequency
(Freq PLD)
MCU ALE frequency (Freq ALE)
% Flash memory Access
% SRAM access
% I/O access
Operational Modes
% Normal
% Power-down Mode
Number of product terms used
(from fitter report)
% of total product terms
Turbo Mode
= 45 PT
= 45/182 = 24.7%
= Off
Calculation (using typical values)
I
CC
total
= I
CC
(MCUactive) x %MCUactive + I
CC
(PSDactive) x %PSDactive + I
PD
(pwrdown) x %pwrdown
I
CC
(MCUactive)
I
PD
(pwrdown)
I
CC
(PSDactive)
= 20mA
= 250µA
= I
CC
(ac) + I
CC
(dc)
= %flash x 2.5mA/MHz x Freq ALE
+ %SRAM x 1.5mA/MHz x Freq ALE
+ % PLD x (from graph using Freq PLD)
= 0.8 x 2.5mA/MHz x 2MHz + 0.15 x 1.5mA/MHz x 2MHz + 24mA
= (4 + 0.45 + 24) mA
= 28.45mA
I
CC
total
= 20mA x 40% + 28.45mA x 40% + 250µA x 60%
= 8mA + 11.38mA + 150µA
= 19.53mA
This is the operating power with no Flash memory Erase or Program cycles in progress. Calculation is based on all I/O
pins being disconnected and I
OUT
= 0mA.
= 40%
= 60%
= 8MHz
= 2MHz
= 80%
= 15%
= 5% (no additional power above base)
= 12MHz
136/170
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