micrf113 Micrel Semiconductor, micrf113 Datasheet - Page 12

• Manufacturer Part Number: micrf113
• Description: Qwikradio Ask Transmitter
• Manufacturer: Micrel Semiconductor

When the ESR of crystal is at 300Ω, the crystal
parameter limits are:
ESR
C
C
C
PLL ×32
The function of PLL×32 is to provide a stable carrier
frequency for transmission. It is a “divide by 32” phase
locked loop oscillator.
Power Amplifier
The power amplifier serves two purposes: 1) to buffer
the VCO from external elements and 2) to amplify the
phase locked signal. The power amplifier can produce
+10dBm at 3V (typical).
Micrel, Inc.
June 2008
PAR
MO
LOAD
C
MO
ESR
CRYSTAL MODEL
Figure 4. Reference Oscillator ASK Operation
300Ω
2 to 5pF
10 to 40fF
10 to 30pF
C
PAR
C
C
LOAD
LOAD
MICRF113 ASK
XTLOUT
VSS
XTLIN
12
Enable Control
Enable control gates the ASK data. It only allows
transmission when Lock, Amplitude and Under Voltage
Detect conditions are valid.
Under Voltage Detect
“Under voltage detect” block senses operating voltage.
If the operating voltage falls below 1.6V, “under voltage
detect” block will send a signal to “enable control” block
to disable the PA.
[phone]
M9999-060208
MICRF113