N2HET1_LOOP_SYNC
EXT_LOOP_SYNC
N2HET2
N2HET1
2 VCLK3 cycles
Pulse Stretch
SYNCI
ePWM1
PINMMR165[24]=0 and PINMMR165[25]=1
ePWM1_SYNCI
Double
synch
6-bit
counter
ePWM1SYNCI
Control of Special Multiplexed Options
320
SPNU563A – March 2018
Copyright © 2018, Texas Instruments Incorporated
I/O Multiplexing and Control Module (IOMM)
6.5.7 Control for Synchronizing Time Bases for All ePWMx Modules
The ePWMx modules implement a mechanism that allows their time bases to be synchronized. This is
done by using a signal called TBCLKSYNC, which is a common input to all the ePWMx modules. This
TBCLKSYNC is generated by a register bit in the I/O multiplexing module. PINMMR166[1] is the
TBCLKSYNC signal. This bit is cleared (0) by default.
When TBCLKSYNC = 0, the time-base clock of all ePWMx modules is stopped. This is the default
condition.
When TBCLKSYNC = 1, the time-base clocks of all ePWMx modules are started aligned to the rising edge
of the TBCLKSYNC signal.
The correct procedure for enabling and synchronizing the time-base clocks of all the ePWMx modules is:
1. Enable the clocks to the desired individual ePWMx modules if they have been disabled
2. Set TBCLKSYNC = 0. This will stop the time-base clocks of any enabled ePWMx module.
3. Configure the time-base clock prescaler values and desired ePWM modes.
4. Set TBCLKSYNC = 1.
6.5.8 Control for Synchronizing all ePWMx Modules to N2HET1 Module Time-Base
Some applications require a synchronized time base for all PWM signals generated by the microcontroller.
The N2HET1 module uses a time base that is created by configuring the high-resolution and loop-
resolution prescalers in the N2HET1 module control registers. The N2HET1 module outputs the loop-
resolution clock signal (N2HET1_LOOP_SYNC) so that other timer modules on the microcontroller can
use it to synchronize their time bases to the N2HET1 loop-resolution clock.
There is a dedicated connection between the N2HET1 and N2HET2 modules, which allows the N2HET2
to use the N2HET1_LOOP_SYNC signal to synchronize its own time base to that of N2HET1.
The seven ePWMx modules can also optionally use the N2HET1_LOOP_SYNC for their time-base
synchronization using a specially designed scheme.
Figure 6-7. Synchronizing ePWMx Modules to N2HET1 Time-Base