C8051F966-A-GQ Silicon Labs, C8051F966-A-GQ Datasheet - Page 295

• Manufacturer Part Number: C8051F966-A-GQ
• Description: 8-bit Microcontrollers - MCU 32KB DC-DC LCD AES
• Manufacturer: Silicon Labs

Specifications of C8051F966-A-GQ

• Rohs: yes
• Core: 8051
• Processor Series: C8051
• Data Bus Width: 8 bit
• Maximum Clock Frequency: 24.5 MHz
• Program Memory Size: 32 KB
• Data Ram Size: 8 KB
• On-chip Adc: Yes
• Operating Supply Voltage: 1.8 V to 3.8 V
• Operating Temperature Range: - 40 C to + 85 C
• Package / Case: QFP-80
• Mounting Style: SMD/SMT

24. SmaRTClock (Real Time Clock)
C8051F96x devices include an ultra low power 32-bit SmaRTClock Peripheral (Real Time Clock) with
alarm. The SmaRTClock has a dedicated 32 kHz oscillator that can be configured for use with or without a
crystal. No external resistor or loading capacitors are required. The on-chip loading capacitors are pro-
grammable to 16 discrete levels allowing compatibility with a wide range of crystals. The SmaRTClock can
operate directly from a 1.8–3.6 V battery voltage and remains operational even when the device goes into
its lowest power down mode. The SmaRTClock output can be buffered and routed to a GPIO pin to provide
an accurate, low frequency clock to other devices while the MCU is in its lowest power down mode (see
“PMU0MD: Power Management Unit Mode” on page 267 for more details). C8051F96x devices also sup-
port an ultra low power internal LFO that reduces sleep mode current.
The SmaRTClock allows a maximum of 36 hour 32-bit independent time-keeping when used with a
32.768 kHz Watch Crystal. The SmaRTClock provides an Alarm and Missing SmaRTClock events, which
could be used as reset or wakeup sources. See Section “22. Reset Sources” on page 278 and Section
“19. Power Management” on page 257 for details on reset sources and low power mode wake-up sources,
respectively.
XTAL4
Registers
Programmable Load Capacitors
Internal
SmaRTClock State Machine
w/ 3 Independent Alarms
SmaRTClock
SmaRTClock Oscillator
Figure 24.1. SmaRTClock Block Diagram
ALARMnBn
CAPTUREn
RTC0XCN
RTC0XCF
RTC0CN
RTC0CF
XTAL3
Wake-Up
Interrupt
Rev. 0.5
RTCOUT
RTC0KEY
RTC0ADR
RTC0DAT
Registers
Interface
SmaRTClock
32-Bit
Timer
LFO
Power/
Clock
Mgmt
C8051F96x
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