CS5535-UDCF AMD (ADVANCED MICRO DEVICES), CS5535-UDCF Datasheet - Page 157

• Manufacturer Part Number: CS5535-UDCF
• Manufacturer: AMD (ADVANCED MICRO DEVICES)

Specifications of CS5535-UDCF

• Operating Temperature (min): 0C
• Operating Temperature (max): 85C
• Operating Temperature Classification: Commercial
• Mounting: Surface Mount
• Lead Free Status / RoHS Status: Compliant

Real-Time Clock Features
5.14
The Real-Time Clock (RTC) consists of three main blocks:
the digital section, the analog section, and the level-shifter
block (see Figure 5-47). The digital section contains the
bus interface, RAM, voltage control, time generator, and
the time keeper. The analog section contains the voltage
switch and low power crystal oscillator. Finally, the level
shifter block provides the appropriate voltage level transla-
tion of signals to and from the RTC block. Level shifters are
needed because the RTC is powered by the V
the analog section), which is different from the V
V
Features
• Accurate timekeeping and calendar management
• Alarm at a predetermined time and/or date
• Three programmable interrupt sources
AMD Geode™ CS5535 Companion Device Data Book
CORE_VSB
KHZ32_XCO
KHZ32_XCI
V
Real-Time Clock Features
IO_VSB
power domains.
V
BAT
Index
Voltage
Sense
Data & Ctrls
Local Bus
Ctrl_Reg A, B, C, D
Low Power Osc.
Voltage Control
Bus Interface
242x8 Bit RAM
Voltage Switch
Gated Clocks
Read
Data
Index_Reg
Level Shifter
RAM I/F
Voltage
Select
Write
Data
Figure 5-47. RTC Block Diagram
PP
32 kHz Clock
CORE
(output of
V
and
PP
• Valid timekeeping during power-down, by utilizing
• 242 bytes of battery-backed RAM
• RAM lock schemes to protect its content
• Internal oscillator circuit (the crystal itself is off-chip), or
• A century counter
• Additional low-power features such as:
• Software compatible with the DS1287 and MC146818
external battery backup
external clock supply for the 32.768 kHz clock
— Automatic switching from battery to V
— Internal power monitoring on the VRT bit
— Oscillator disabling to save battery during storage
#0
q
rtc_monthday
rtc_weekday
rtc_seconds
rtc_minutes
Time Generator
rtc_months
Time Keeper
rtc_hours
rtc_years
#1
q
31506B
#14
Update
Clock
q
SB
157