PXD10RM Datasheet, PDF (1152/1332 Pages) Freescale Semiconductor, Inc – PXD10 Microcontroller

Table 35-20. Impact of MCCTL1[RECIRC] and MCDCx[SIGN[4]] Bit on the PWM Output (continued)
Output Mode
MCCTL1[RECIRC] MCDCx[SIGN[4]]
MnCyM
MnCyP
(Dual) Full H-Bridge
1
0
0
PWM²
(Dual) Full H-Bridge
1
1
PWM
0
Half H-Bridge: PWM on MnCyM
Don’t care
Don’t care
PWM
—³
Half H-Bridge: PWM on MnCyP
Don’t care
Don’t care
—
PWM
1 _{PWM: The PWM signal is low active. e.g., the waveform starts with 0 in left aligned mode. Output M generates the}
PWM signal. Output P is static high.
2 _{PWM: The PWM signal is high active. e.g., the waveform starts with 1 in left aligned mode. output P generates the}
PWM signal. Output M is static low.
3 _{The state of the output transistors is not controlled by the SMC.}
35.4.1.3.3 Recirculation Bit (MCCTL1[RECIRC])
The MCCTL1[RECIRC] bit controls the flow of the recirculation current of the load. Setting
MCCTL1[RECIRC] = 0 will cause recirculation current to flow through the high side transistors, and
MCCTL1[RECIRC] = 1 will cause the recirculation current to flow through the low side transistors. The
MCCTL1[RECIRC] bit is only active in (dual) full H-bridge modes.
Effectively, MCCTL1[RECIRC] = 0 will cause a static high output on the output terminal not driven by
the PWM, MCCTL1[RECIRC] = 1 will cause a static low output on the output terminals not driven by the
PWM. To achieve the same current direction, the MCDCx[SIGN[4]] bit behavior is inverted if
MCCTL1[RECIRC] = 1. Figure 35-22, Figure 35-23, Figure 35-24, and Figure 35-25 illustrate the effect
of the MCCTL1[RECIRC] bit in (dual) full H-bridge modes.
MCCTL1[RECIRC] bit must be changed only while no PWM channel is operated in (dual) full H-bridge
mode.
35-24
PXD10 Microcontroller Reference Manual, Rev. 1
Preliminary—Subject to Change Without Notice
Freescale Semiconductor