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2014-07-02 - Gecko Family - d0001_Rev1.30
286
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DS
up
= CCVx/TOP
(19.5)
19.3.2.7 Up/Down-count (Dual-slope) PWM
If the counter is set to up-down count and the Compare/Capture channel is put in PWM mode, dual
slope PWM output will be generated by Figure 19.19 (p. 286) .The resolution (in bits) is given by
Equation 19.6 (p. 286) .
Figure 19.19. TIMER Up/Down-count PWM Generation
0
TIMERn_TOP
TIMERn_CCx _CCV
TIMn_CCx
Overflow
Com pare m at ch
Buffer updat e
TIMER Up/Down-count PWM Resolution Equation
R
PWM
up/down
= log(TOP+1)/log(2)
(19.6)
The PWM frequency is given by Equation 19.7 (p. 286) :
TIMER Up/Down-count PWM Frequency Equation
f
PWM
up/down
= f
HFPERCLK
/ ( 2^(PRESC+1) x TOP)
(19.7)
The high duty cycle is given by Equation 19.8 (p. 286)
TIMER Up/Down-count Duty Cycle Equation
DS
up/down
= CCVx/TOP
(19.8)
19.3.3 Dead-Time Insertion Unit (TIMER0 only)
The Dead-Time Insertion Unit aims to make control of BLDC motors safer and more efficient
by introducing complementary PWM outputs with dead-time insertion and fault handling, see
Figure 19.20 (p. 286) .
Figure 19.20. TIMER Dead-Time Insertion Unit Overview
Dead t im e
insert ion
Original PWM (TIM0_CCx _pre)
Fault
handling
Prim ary out put (TIM0_CCx )
Com plem ent ary out put (TIM0_CDTIx )
Fault sources
Summary of Contents for EFM32G
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