DS1921G-F5N MAXIM [Maxim Integrated Products], DS1921G-F5N Datasheet - Page 7

• Manufacturer Part Number: DS1921G-F5N
• Description: Thermochron iButton
• Manufacturer: MAXIM [Maxim Integrated Products]

The DS1921G Thermochron iButton is an ideal device
to monitor the temperature of any object it is attached
to or shipped with, such as perishable goods or con-
tainers of temperature-sensitive chemicals. The gener-
al-purpose battery-backed SRAM can store an
electronic copy of shipping information, date of manu-
facture and other important data written as clear as well
as encrypted files. Note that the initial sealing level of
the DS1921G achieves IP56. Aging and use conditions
can degrade the integrity of the seal over time, there-
fore, for applications with significant exposure to liq-
uids, sprays, or other similar environments, it is
recommended to place the Thermochron in the DS9107
Figure 1. Block Diagram
_______________________________________________________________________________________
TEMPERATURE
OSCILLATOR
Detailed Description
32.768kHz
1-Wire PORT
CORE
DS1921G
IO
3V LITHIUM
CONTROL REGISTERS,
AND COUNTERS
CONTROL
TIMEKEEPING,
LOGIC
INTERNAL
FUNCTION
CONTROL
ROM
ALARM TIMESTAMP AND
DURATION LOGGING
DATA-LOG MEMORY
GENERAL-PURPOSE
REGISTER PAGE
iButton capsule. The DS9107 provides a watertight
enclosure that has been rated to IP68 (refer to
Application Note 4126: Understanding the IP (Ingress
Protection) Ratings of iButton Data Loggers and
Capsule ).
Figure 1 shows the relationships between the major
control and memory sections of the DS1921G. The
device has seven main data components: 64-bit
lasered ROM; 256-bit scratchpad; 4096-bit general-
purpose SRAM; 256-bit register page of timekeeping,
control, and counter registers; 96 bytes of alarm time-
stamp and duration logging memory; 126 bytes of
HISTOGRAM
MEMORY
MEMORY
SRAM
LASERED
Thermochron iButton
64-BIT
ROM
FUNCTION
CONTROL
MEMORY
PARASITE-POWERED
CIRCUITRY
SCRATCHPAD
256-BIT
Overview
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