52
DS632F1
CS44800
7.3.5
Power Down Output Mode (PDN_OUTPUT_MODE)
Default = 0
0 - PWM Outputs are driven low during power down
1 - PWM Outputs are driven to the inactive state during power down
Function:
This bit is used to select the power-down state of the PWM output signals. When set to 0, each channel
which has been powered down, following the ramp-down cycle if enabled, will drive the output signals,
P and PWMOUTxx-, low.
When set to 1, each channel which has been powered down, following the ramp-down cycle if enabled,
will drive the output signals to the inactive state. P is driven low and PWMOUTxx- is driven
high.
7.3.6
Power Down (PDN)
Default = 1
0 - Normal Operation
1 - Power down
Function:
The entire device will enter a low-power state when this function is enabled, and the contents of the control
registers are retained in this mode. The power-down bit defaults to ‘enabled’ on power-up and must be
disabled before normal operation can occur.
7.4
PWM Channel Power Down Control (address 03h)
7.4.1
Power Down PWM Channels (PDN_PWMB
4
:PDN_PWMA1)
Default = 11111111
0 - Normal Operation
1 - Power down PWM channel
Function:
The specific PWM channel is in the power-down state. All processing is halted for the specific channel,
but does not alter the setup or delay register values. The PWM output signals are driven to the appropriate
logic level as defined by the Power-Down Output Mode bit, PDN_OUTPUT_MODE. When set to normal
operation, the specific channel will power up according to the state of the RAMP[1:0] bits and the channel
output configuration selected. When transitioning from normal operation to power down, the specific chan-
nel will power down according to the state of the RAMP[1:0] bits and the channel output configuration se-
lected. Ramp control is found in
“Ramp Configuration (address 05h)” on page 54
.
7
6
5
4
3
2
1
0
PDN_PWMB4
PDN_PWMA4
PDN_PWMB3
PDN_PWMA3
PDN_PWMB2
PDN_PWMA2
PDN_PWMB1
PDN_PWMA1