C8051F331-GM Silicon Laboratories Inc, C8051F331-GM Datasheet - Page 197
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C8051F331-GM
Manufacturer Part Number
C8051F331-GM
Description
IC 8051 MCU 8K FLASH 20QFN
Manufacturer
Silicon Laboratories Inc
Series
C8051F33xr
Specifications of C8051F331-GM
Program Memory Type
FLASH
Program Memory Size
8KB (8K x 8)
Package / Case
20-QFN
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
Ram Size
768 x 8
Voltage - Supply (vcc/vdd)
2.7 V ~ 3.6 V
Oscillator Type
Internal
Operating Temperature
-40°C ~ 85°C
Processor Series
C8051F3x
Core
8051
Data Bus Width
8 bit
Data Ram Size
768 B
Interface Type
I2C/SMBus/SPI/UART
Maximum Clock Frequency
25 MHz
Number Of Programmable I/os
17
Number Of Timers
4
Operating Supply Voltage
2.7 V to 3.6 V
Maximum Operating Temperature
+ 85 C
Mounting Style
SMD/SMT
3rd Party Development Tools
KSK-SL-TOOLSTICK, PK51, CA51, A51, ULINK2
Development Tools By Supplier
C8051F330DK
Minimum Operating Temperature
- 40 C
On-chip Adc
10 bit, 16 Channel
No. Of I/o's
17
Ram Memory Size
768Byte
Cpu Speed
25MHz
No. Of Timers
4
Rohs Compliant
Yes
Lead Free Status / RoHS Status
Lead free / RoHS Compliant
For Use With
770-1006 - ISP 4PORT FOR SILABS C8051F MCU336-1451 - ADAPTER PROGRAM TOOLSTICK F330336-1264 - DEV KIT FOR C8051F330/F331
Eeprom Size
-
Data Converters
-
Lead Free Status / Rohs Status
Lead free / RoHS Compliant
Other names
336-1265
Available stocks
Company
Part Number
Manufacturer
Quantity
Price
Company:
Part Number:
C8051F331-GM
Manufacturer:
SiliconL
Quantity:
1 630
Part Number:
C8051F331-GM
Manufacturer:
SILICON LABS/芯科
Quantity:
20 000
Part Number:
C8051F331-GMR
Manufacturer:
SILICON LABS/芯科
Quantity:
20 000
19.2.6. 16-Bit Pulse Width Modulator Mode
A PCA module may also be operated in 16-Bit PWM mode. In this mode, the 16-bit capture/compare mod-
ule defines the number of PCA clocks for the low time of the PWM signal. When the PCA counter matches
the module contents, the output on CEXn is asserted high; when the counter overflows, CEXn is asserted
low. To output a varying duty cycle, new value writes should be synchronized with PCA CCFn match inter-
rupts. 16-Bit PWM Mode is enabled by setting the ECOMn, PWMn, and PWM16n bits in the PCA0CPMn
register. For a varying duty cycle, match interrupts should be enabled (ECCFn = 1 AND MATn = 1) to help
synchronize the capture/compare register writes. The duty cycle for 16-Bit PWM Mode is given by
Equation 19.5.
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 19.5, the largest duty cycle is 100% (PCA0CPn = 0), and the smallest duty cycle is
0.0015% (PCA0CPn = 0xFFFF). A 0% duty cycle may be generated by clearing the ECOMn bit to ‘0’.
19.3. Watchdog Timer Mode
A programmable watchdog timer (WDT) function is available through the PCA Module 2. The WDT is used
to generate a reset if the time between writes to the WDT update register (PCA0CPH2) exceed a specified
limit. The WDT can be configured and enabled/disabled as needed by software.
With the WDTE bit set in the PCA0MD register, Module 2 operates as a watchdog timer (WDT). The Mod-
ule 2 high byte is compared to the PCA counter high byte; the Module 2 low byte holds the offset to be
used when WDT updates are performed. The Watchdog Timer is enabled on reset. Writes to some
PCA registers are restricted while the Watchdog Timer is enabled.
PCA0CPLn
Write to
Reset
PCA0CPHn
Write to
0
ENB
ENB
1
W
P
M
1
6
n
1
E
C
O
M
n
PCA0CPMn
C
A
P
P
n
0 0 x 0
C
A
P
N
n
M
A
T
n
PCA Timebase
O
G
T
n
Equation 19.5. 16-Bit PWM Duty Cycle
W
P
M
n
E
C
C
F
n
x
Figure 19.9. PCA 16-Bit PWM Mode
DutyCycle
Enable
PCA0CPHn
PCA0H
=
16-bit Comparator
Rev. 1.7
---------------------------------------------------- -
65536 PCA0CPn
PCA0CPLn
PCA0L
–
65536
Overflow
C8051F330/1/2/3/4/5
match
S
R
SET
CLR
Q
Q
CEXn
Crossbar
Port I/O
201