T48C862M-R3-TNS Atmel, T48C862M-R3-TNS Datasheet - Page 24

• Manufacturer Part Number: T48C862M-R3-TNS
• Description: IC MON TIRE PRESS 315MHZ 24SOIC
• Manufacturer: Atmel

Specifications of T48C862M-R3-TNS

• Frequency: 315MHz
• Modulation Or Protocol: FM, FSK
• Data Rate - Maximum: 32 kBaud
• Power - Output: 10dBm
• Current - Transmitting: 9.5mA
• Data Interface: PCB, Surface Mount
• Antenna Connector: PCB, Surface Mount
• Memory Size: 1KB EEPROM, 1KB RAM
• Voltage - Supply: 2 V ~ 4 V
• Operating Temperature: -40°C ~ 125°C
• Package / Case: 24-SOIC (0.200", 5.30mm Width)
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Features: -
• Applications: -

Clock Generation
Clock Module
24
T48C862-R3
Figure 18. Internal Supply Voltage Supervisor
Figure 19. External Input Voltage Supervisor
The T48C862-R3 contains a clock module with 4 different internal oscillator types: two
RC-oscillators, one 4-MHz crystal oscillator and one 32-kHz crystal oscillator. The pins
OSC1 and OSC2 are the interface to connect a crystal either to the 4-MHz, or to the
32-kHz crystal oscillator. OSC1 can be used as input for external clocks or to connect an
external trimming resistor for the RC-oscillator 2. All necessary circuitry, except the crys-
tal and the trimming resistor, is integrated on-chip. One of these oscillator types or an
external input clock can be selected to generate the system clock (SYSCL).
In applications that do not require exact timing, it is possible to use the fully integrated
RC-oscillator 1 without any external components. The RC-oscillator 1 center frequency
tolerance is better than ± 50%. The RC-oscillator 2 is a trimmable oscillator whereby the
oscillator frequency can be trimmed with an external resistor attached between OSC1
and V
with a tolerance of ± 15% over the full operating temperature and voltage range.
The clock module is programmable via software with the clock management register
(CM) and the system configuration register (SC). The required oscillator configuration
can be selected with the OS1-bit and the OS0-bit in the SC-register. A programmable
4-bit divider stage allows the adjustment of the system clock speed. A special feature of
the clock management is that an external oscillator may be used and switched on and
off via a port pin for the power-down mode. Before the external clock is switched off, the
internal RC-oscillator 1 must be selected with the CCS-bit and then the SLEEP mode
may be activated. In this state an interrupt can wake up the controller with the RC-oscil-
lator, and the external oscillator can be activated and selected by software. A
synchronization stage avoids too short clock periods if the clock source or the clock
speed is changed. If an external input clock is selected, a supervisor circuit monitors the
external input and generates a hardware reset if the external clock source fails or drops
below 500 kHz for more than 1 ms.
DD
3.0 V
2.6 V
2.2 V
. In this configuration, the RC-oscillator 2 frequency can be maintained stable
V
1.3 V
VMI
VMS = 1
DD
Low threshold
Middle threshold
High threshold
Negative slope
Positive slope
VMS = 1
VMS = 0
Internal reference level
Interrupt positive slope
Interrupt negative slope
VMS = 1
VMS = 0
Low threshold
Middle threshold
High threshold
VMS = 0
4554A–4BMCU–02/03
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