LM3S1937-IBZ50 Luminary Micro, Inc, LM3S1937-IBZ50 Datasheet - Page 422
LM3S1937-IBZ50
Manufacturer Part Number
LM3S1937-IBZ50
Description
Lm3s1937 Arm Microcontroller
Manufacturer
Luminary Micro, Inc
Datasheet
1.LM3S1937-IBZ50.pdf
(524 pages)
Available stocks
Company
Part Number
Manufacturer
Quantity
Price
Company:
Part Number:
LM3S1937-IBZ50-A2
Manufacturer:
TI
Quantity:
269
Company:
Part Number:
LM3S1937-IBZ50-A2
Manufacturer:
Texas Instruments
Quantity:
10 000
Company:
Part Number:
LM3S1937-IBZ50-A2T
Manufacturer:
Texas Instruments
Quantity:
10 000
- Current page: 422 of 524
- Download datasheet (6Mb)
Pulse Width Modulator (PWM)
17.2
17.2.1
17.2.2
422
Figure 17-2. PWM Module Block Diagram
PWM Clock
Functional Description
PWM Timer
The timer in each PWM generator runs in one of two modes: Count-Down mode or Count-Up/Down
mode. In Count-Down mode, the timer counts from the load value to zero, goes back to the load
value, and continues counting down. In Count-Up/Down mode, the timer counts from zero up to the
load value, back down to zero, back up to the load value, and so on. Generally, Count-Down mode
is used for generating left- or right-aligned PWM signals, while the Count-Up/Down mode is used
for generating center-aligned PWM signals.
The timers output three signals that are used in the PWM generation process: the direction signal
(this is always Low in Count-Down mode, but alternates between Low and High in Count-Up/Down
mode), a single-clock-cycle-width High pulse when the counter is zero, and a single-clock-cycle-width
High pulse when the counter is equal to the load value. Note that in Count-Down mode, the zero
pulse is immediately followed by the load pulse.
PWM Comparators
There are two comparators in each PWM generator that monitor the value of the counter; when
either match the counter, they output a single-clock-cycle-width High pulse. When in Count-Up/Down
mode, these comparators match both when counting up and when counting down; they are therefore
qualified by the counter direction signal. These qualified pulses are used in the PWM generation
process. If either comparator match value is greater than the counter load value, then that comparator
never outputs a High pulse.
Figure 17-3 on page 423 shows the behavior of the counter and the relationship of these pulses
when the counter is in Count-Down mode. Figure 17-4 on page 423 shows the behavior of the counter
and the relationship of these pulses when the counter is in Count-Up/Down mode.
Interrupts /
Triggers
PWM Generator Block
PWMnCOUNT
PWMnLOAD
PWMnCMPA
PWMnCMPB
PWMnCTL
zero
load
dir
cmp A
cmp B
Preliminary
Interrupt and
PWMnINTEN
PWMnGENA
PWMnGENB
Generator
PWMnRIS
PWMnISC
Trigger
PWMnMINFLTPER
PWMnFLTSTAT0
PWMnFLTSRC0
PWMnFLTSEN
PWMnDBRISE
PWMnDBFALL
PWMnDBCTL
July 25, 2008
PWMn_Fault
PWMn_A
PWMn_B
Fault(s)
Related parts for LM3S1937-IBZ50
Image
Part Number
Description
Manufacturer
Datasheet
Request
R
Part Number:
Description:
Lm3s1110 Arm Microcontroller
Manufacturer:
Luminary Micro, Inc
Datasheet:
Part Number:
Description:
Lm3s1133 Arm Microcontroller
Manufacturer:
Luminary Micro, Inc
Datasheet:
Part Number:
Description:
Lm3s1138 Arm Microcontroller
Manufacturer:
Luminary Micro, Inc
Datasheet:
Part Number:
Description:
Lm3s1150 Arm Microcontroller
Manufacturer:
Luminary Micro, Inc
Datasheet:
Part Number:
Description:
Lm3s1162 Arm Microcontroller
Manufacturer:
Luminary Micro, Inc
Datasheet:
Part Number:
Description:
Lm3s1165 Arm Microcontroller
Manufacturer:
Luminary Micro, Inc
Datasheet:
Part Number:
Description:
Lm3s1332 Arm Microcontroller
Manufacturer:
Luminary Micro, Inc
Datasheet:
Part Number:
Description:
Lm3s1435 Arm Microcontroller
Manufacturer:
Luminary Micro, Inc
Datasheet:
Part Number:
Description:
Lm3s1439 Arm Microcontroller
Manufacturer:
Luminary Micro, Inc
Datasheet:
Part Number:
Description:
Lm3s1512 Arm Microcontroller
Manufacturer:
Luminary Micro, Inc
Datasheet:
Part Number:
Description:
Lm3s1538 Arm Microcontroller
Manufacturer:
Luminary Micro, Inc
Datasheet:
Part Number:
Description:
Lm3s1601 Arm Microcontroller
Manufacturer:
Luminary Micro, Inc
Datasheet:
Part Number:
Description:
Lm3s1607 Arm Microcontroller
Manufacturer:
Luminary Micro, Inc
Datasheet:
Part Number:
Description:
Lm3s1608 Arm Microcontroller
Manufacturer:
Luminary Micro, Inc
Datasheet:
Part Number:
Description:
Lm3s1620 Arm Microcontroller
Manufacturer:
Luminary Micro, Inc
Datasheet: