RFW-D100 Vishay, RFW-D100 Datasheet - Page 11

• Manufacturer Part Number: RFW-D100
• Manufacturer: Vishay

Specifications of RFW-D100

• Operating Temperature (min): 0C
• Operating Temperature (max): 70C
• Operating Temperature Classification: Commercial
• Package Type: LQFP
• Operating Supply Voltage (min): 2.7V
• Operating Supply Voltage (typ): 3.3V
• Operating Supply Voltage (max): 3.6V
• Lead Free Status / Rohs Status: Supplier Unconfirmed

LOW FREQUENCY RC OSCILLATOR
The RFW-D100 includes a built-in low frequency RC
oscillator that enables the full transceiver chipset to
maintain a very low current consumption once the
system enters into sleep mode operation.
This RC oscillator is used as a clock source for the
Operation Frequency: 10 KHz at Cext = 30 pF
(Frequency is linear with Cext value).
Operation current consumption: < 7 µA
Frequency Deviation : +/- 20 % over temperature.
WDT
The WDT is used as a communication watchdog in the
system. Its purpose is to wake up the MCU from power
down or idle mode, whenever a packet is transmitted
or a packet is received.
The watchdog timer (WDT) is a separate module
inside the RFW-D100. A different oscillator from all the
other modules in the RFW-D100 drives it. The
watchdog clock source is an internal 10 kHz RC oscil-
lator that uses an external capacitor to set its fre-
Document Number 84675
Rev. 1.1, 22-Jan-07
Ext RC CAP
For more information please contact: [e-mail]
Figure 6. RC Oscillator Block Diagram
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Req
communication watchdog (WDT) in the RFW-D100.
The RC oscillator is enabled/disabled by the SCR1(5)
flag.
quency. The RC oscillator works only when SCR1(4) is
set high.
Controlling the WDT is done through three registers
(SCR1, FRC-H, FRC-L) and WDT_RST input pin.
When modifying one of these registers, WDT must be
disabled (SCR1(3) – WDT_EN = ‘0’).
The WDT_RST pin is used to reset the watchdog
counter, i.e. set its value to 0. If the watchdog is
enabled and WDT_RST is set low, then the watchdog
counter runs normally. When WDT_RST is set high,
the watchdog counter value is 0.
If WDT_RST is set high while the WDT output pin is
high, then the WDT pulse will be reset and the WDT
output pin will be zero (as default).
Buff
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10KHz Clock
Vishay RFWaves
RFW-D100
www.vishay.com
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