C8051F352-GQR Silicon Laboratories Inc, C8051F352-GQR Datasheet - Page 207

• Manufacturer Part Number: C8051F352-GQR
• Description: IC 8051 MCU 8K FLASH 32LQFP
• Manufacturer: Silicon Laboratories Inc
• Series: C8051F35xr

Specifications of C8051F352-GQR

• Core Processor: 8051
• Core Size: 8-Bit
• Speed: 50MHz
• Connectivity: SMBus (2-Wire/I²C), SPI, UART/USART
• Peripherals: POR, PWM, Temp Sensor, WDT
• Number Of I /o: 17
• Program Memory Size: 8KB (8K x 8)
• Program Memory Type: FLASH
• Ram Size: 768 x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 3.6 V
• Data Converters: A/D 8x16b; D/A 2x8b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 32-LQFP
• Core: 8051
• Processor Series: C8051F3x
• Data Bus Width: 8 bit
• Maximum Clock Frequency: 50 MHz
• Data Ram Size: 768 B
• Data Rom Size: 128 B
• On-chip Adc: Yes
• Number Of Programmable I/os: 17
• Number Of Timers: 4 bit
• Operating Supply Voltage: 2.7 V to 3.6 V
• Mounting Style: SMD/SMT
• A/d Bit Size: 16 bit
• A/d Channels Available: 8
• Height: 1.4 mm
• Interface Type: I2C, SMBus, SPI, UART
• Length: 7 mm
• Maximum Operating Temperature: + 85 C
• Minimum Operating Temperature: - 40 C
• Supply Voltage (max): 3.6 V
• Supply Voltage (min): 2.7 V
• Width: 7 mm
• For Use With: 336-1083 - DEV KIT FOR F350/351/352/353
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Lead Free Status / Rohs Status: Details

22.3. Timer 3
Timer 3 is a 16-bit timer formed by two 8-bit SFRs: TMR3L (low byte) and TMR3H (high byte). Timer 3 may
operate in 16-bit auto-reload mode or (split) 8-bit auto-reload mode. The T3SPLIT bit (TMR3CN.3) defines
the Timer 3 operation mode.
Timer 3 may be clocked by the system clock, the system clock divided by 12, or the external oscillator
source divided by 8. The external clock mode is ideal for real-time clock (RTC) functionality, where the
internal oscillator drives the system clock while Timer 3 (and/or the PCA) is clocked by an external preci-
sion oscillator. Note that the external oscillator source divided by 8 is synchronized with the system clock.
22.3.1. 16-bit Timer with Auto-Reload
When T3SPLIT (TMR3CN.3) is zero, Timer 3 operates as a 16-bit timer with auto-reload. Timer 3 can be
clocked by SYSCLK, SYSCLK divided by 12, or the external oscillator clock source divided by 8. As the
16-bit timer register increments and overflows from 0xFFFF to 0x0000, the 16-bit value in the Timer 3
reload registers (TMR3RLH and TM3RLL) is loaded into the Timer 3 register as shown in Figure 22.6, and
the Timer 3 High Byte Overflow Flag (TMR3CN.7) is set. If Timer 3 interrupts are enabled, an interrupt will
be generated each Timer 3 overflow. Additionally, if Timer 3 interrupts are enabled and the TF3LEN bit is
set (TMR3CN.5), an interrupt will be generated each time the lower 8 bits (TMR3L) overflow from 0xFF to
0x00.
External Clock / 8
SYSCLK / 12
SYSCLK
T3XCLK
0
1
Figure 22.6. Timer 3 16-Bit Mode Block Diagram
T
M
H
3
M
T
3
L
CKCON
T
M
H
2
M
T
2
L
0
1
M
T
1
M
T
0
S
C
A
1
S
C
A
0
TR3
TCLK
Rev. 1.1
TMR3RLL TMR3RLH
TMR3L
TMR3H
Reload
C8051F350/1/2/3
TF3LEN
T3SPLIT
T3XCLK
TF3H
TF3L
TR3
Interrupt
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