DS3234S# Maxim Integrated Products, DS3234S# Datasheet - Page 9

• Manufacturer Part Number: DS3234S#
• Description: IC RTC W/TCXO 20-SOIC
• Manufacturer: Maxim Integrated Products
• Type: Clock/Calendar/TCXO/Crystalr

Specifications of DS3234S#

• Memory Size: 2K (256 x 8)
• Time Format: HH:MM:SS (12/24 hr)
• Date Format: YY-MM-DD-dd
• Interface: SPI, 3-Wire Serial
• Voltage - Supply: 2 V ~ 5.5 V
• Operating Temperature: 0°C ~ 70°C
• Mounting Type: Surface Mount
• Package / Case: 20-SOIC (7.5mm Width)
• Function: Clock/Calendar/Alarm/Battery Backup/Interrupt
• Rtc Memory Size: 256 Byte
• Supply Voltage (max): 5.5 V
• Supply Voltage (min): 2 V
• Maximum Operating Temperature: + 70 C
• Minimum Operating Temperature: 0 C
• Mounting Style: SMD/SMT
• Rtc Bus Interface: Serial (4-Wire, SPI)
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

The DS3234 is a TCXO and RTC with integrated crystal
and 256 bytes of SRAM. An integrated sensor periodi-
cally samples the temperature and adjusts the oscilla-
tor load to compensate for crystal drift caused by
temperature variations. The DS3234 provides user-
selectable sample rates. This allows the user to select
a temperature sensor sample rate that allows for vari-
ous temperature rates of change, while minimizing cur-
rent consumption by temperature sensor sampling. The
user should select a sample rate based upon the
SCLK
DOUT
SCLK
V
GND
V
DIN
BAT
CS
CC
X1
X2
Detailed Description
Extremely Accurate SPI Bus RTC with
SPI INTERFACE AND
ADDRESS REGISTER
CAPACITOR ARRAY
POWER CONTROL
OSCILLATOR AND
DECODE
_____________________________________________________________________
DS3234
Integrated Crystal and SRAM
CONTROL LOGIC/
TEMPERATURE
SENSOR
DIVIDER
expected temperature rate of change, with faster sam-
ple rates for applications where the ambient tempera-
ture changes significantly over a short time. The TCXO
provides a stable and accurate reference clock, and
maintains the RTC to within ±2 minutes per year accu-
racy from -40°C to +85°C. The TCXO frequency output
is available at the 32kHz pin. The RTC is a low-power
clock/calendar with two programmable time-of-day
alarms and a programmable square-wave output. The
INT/SQW provides either an interrupt signal due to
alarm conditions or a square-wave output. The
clock/calendar provides seconds, minutes, hours, day,
SQUARE-WAVE BUFFER;
CLOCK AND CALENDAR
CONTROL AND STATUS
VOLTAGE REFERENCE;
DEBOUNCE CIRCUIT;
PUSHBUTTON RESET
INT/SQW CONTROL
USER BUFFER
REGISTERS
REGISTERS
(7 BYTES)
SRAM
Block Diagram
V
CC
N
N
32kHz
INT/SQW
RST
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