DS2251T-32-16 Maxim Integrated Products, DS2251T-32-16 Datasheet - Page 8

• Manufacturer Part Number: DS2251T-32-16
• Description: IC MICROCNTRLR 32K 16MHZ 72-SIMM
• Manufacturer: Maxim Integrated Products
• Series: DS225xr

Specifications of DS2251T-32-16

• Core Processor: 8051
• Core Size: 8-Bit
• Speed: 16MHz
• Connectivity: SIO, UART/USART
• Peripherals: Power-Fail Reset, WDT
• Number Of I /o: 32
• Program Memory Type: SRAM
• Ram Size: 32K x 8
• Voltage - Supply (vcc/vdd): 4.5 V ~ 5.5 V
• Oscillator Type: External
• Operating Temperature: 0°C ~ 70°C
• Package / Case: 72-SIMM
• Processor Series: DS2251T
• Core: 8051
• Data Bus Width: 8 bit
• Program Memory Size: 32 KB
• Data Ram Size: 32 KB
• Interface Type: UART
• Maximum Clock Frequency: 16 MHz
• Number Of Programmable I/os: 32
• Number Of Timers: 2
• Operating Supply Voltage: 4.75 V to 5.25 V
• Maximum Operating Temperature: + 70 C
• Mounting Style: SMD/SMT
• Minimum Operating Temperature: 0 C
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Eeprom Size: -
• Program Memory Size: -
• Data Converters: -
• Lead Free Status / Rohs Status: No

DS2251T
DS2251T MEMORY MAP WITH (PES = 1) Figure 4
POWER MANAGEMENT
The DS2251T monitors V
to provide power-fail reset, early warning power-fail interrupt, and
CC
switchover to lithium backup. It uses an internal band-gap reference in determining the switch points.
These are called V
, V
, and V
, respectively. When V
drops below V
, the DS2251T will
PFW
CCMIN
LI
CC
PFW
perform an interrupt vector to location 2Bh if the power-fail warning is enabled. Full processor operation
continues regardless. When power falls further to V
, the DS2251T invokes a reset state. No further
CCMIN
code execution will be performed unless power rises back above V
. All decoded chip enables and
CCMIN
the R/
signal go to an inactive (logic 1) state. The
signal will be driven to a logic 0. V
is still
W
VRST
CC
the power source at this time. When V
drops further to below V
, internal circuitry will switch to the
CC
LI
built-in lithium cell for power. The majority of internal circuits will be disabled and the remaining
nonvolatile states will be retained.
will be driven to a logic 0. The Secure Microcontroller User’s
PF
Guide has more information on this topic. The trip points V
and V
are listed in the electrical
CCMIN
PFW
specifications.
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