C8051T633-GM Silicon Laboratories Inc, C8051T633-GM Datasheet - Page 199
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C8051T633-GM
Manufacturer Part Number
C8051T633-GM
Description
IC MCU 4KB 20PIN QFN
Manufacturer
Silicon Laboratories Inc
Series
C8051T63xr
Specifications of C8051T633-GM
Core Processor
8051
Core Size
8-Bit
Speed
25MHz
Connectivity
SMBus (2-Wire/I²C), SPI, UART/USART
Peripherals
POR, PWM, WDT
Number Of I /o
17
Program Memory Size
4KB (4K x 8)
Program Memory Type
OTP
Ram Size
768 x 8
Voltage - Supply (vcc/vdd)
1.8 V ~ 3.6 V
Oscillator Type
Internal
Operating Temperature
-40°C ~ 85°C
Package / Case
20-QFN
Processor Series
C8051T6x
Core
8051
Data Bus Width
8 bit
Data Ram Size
768 B
Interface Type
UART, SPI, SMBus
Maximum Clock Frequency
25 MHz
Number Of Programmable I/os
17
Number Of Timers
4 x 16-bit
Operating Supply Voltage
1.8 V to 3.6 V
Maximum Operating Temperature
+ 85 C
Mounting Style
SMD/SMT
3rd Party Development Tools
PK51, CA51, A51, ULINK2
Development Tools By Supplier
C8051T630DK
Minimum Operating Temperature
- 40 C
For Use With
336-1464 - KIT DEV FOR C8051T630 FAMILY
Lead Free Status / RoHS Status
Lead free / RoHS Compliant
Eeprom Size
-
Data Converters
-
Lead Free Status / Rohs Status
Details
Other names
336-1461-5
Available stocks
Company
Part Number
Manufacturer
Quantity
Price
Company:
Part Number:
C8051T633-GM
Manufacturer:
Silicon
Quantity:
270
25.3.5.1. 8-bit Pulse Width Modulator Mode
The duty cycle of the PWM output signal in 8-bit PWM mode is varied using the module's PCA0CPLn cap-
ture/compare register. When the value in the low byte of the PCA counter/timer (PCA0L) is equal to the
value in PCA0CPLn, the output on the CEXn pin will be set. When the count value in PCA0L overflows, the
CEXn output will be reset (see Figure 25.8). Also, when the counter/timer low byte (PCA0L) overflows from
0xFF to 0x00, PCA0CPLn is reloaded automatically with the value stored in the module’s capture/compare
high byte (PCA0CPHn) without software intervention. Setting the ECOMn and PWMn bits in the
PCA0CPMn register, and setting the CLSEL bits in register PCA0PWM to 00b enables 8-Bit Pulse Width
Modulator mode. If the MATn bit is set to 1, the CCFn flag for the module will be set each time an 8-bit
comparator match (rising edge) occurs. The COVF flag in PCA0PWM can be used to detect the overflow
(falling edge), which will occur every 256 PCA clock cycles. The duty cycle for 8-Bit PWM Mode is given in
Equation 25.2.
Important Note About Capture/Compare Registers: When writing a 16-bit value to the PCA0 Cap-
ture/Compare registers, the low byte should always be written first. Writing to PCA0CPLn clears the
ECOMn bit to 0; writing to PCA0CPHn sets ECOMn to 1.
Using Equation 25.2, the largest duty cycle is 100% (PCA0CPHn = 0), and the smallest duty cycle is
0.39% (PCA0CPHn = 0xFF). A 0% duty cycle may be generated by clearing the ECOMn bit to 0.
PCA0CPLn
Write to
Reset
PCA0CPHn
A
R
S
E
L
0
Write to
C
O
PCA0PWM
E
V
x
C
O
V
F
0
ENB
ENB
1
C
L
S
E
L
1
0
C
L
S
E
L
0
0
W
M
P
1
6
n
0
Figure 25.8. PCA 8-Bit PWM Mode Diagram
E
C
O
M
n
PCA0CPMn
C
A
P
P
n
0 0 x 0
C
N
A
P
n
Equation 25.2. 8-Bit PWM Duty Cycle
M
A
T
n
O
G
T
n
Duty Cycle
W
M
P
n
E
C
C
F
n
x
PCA Timebase
Enable
=
PCA0CPHn
Comparator
PCA0CPLn
Rev. 1.0
-------------------------------------------------- -
PCA0L
256 PCA0CPHn
8-bit
–
256
Overflow
COVF
C8051T630/1/2/3/4/5
match
S
R
SET
CLR
Q
Q
CEXn
Crossbar
Port I/O
199