MC33493 Motorola, MC33493 Datasheet - Page 13

• Manufacturer Part Number: MC33493
• Description: PLL tuned UHF Transmitter for Data Transfer Applications
• Manufacturer: Motorola

OUTPUT POWER MEASUREMENT
The RF output levels given in the electrical characteristics section are measured with a 50Ω load directly
connected to the pin RFOUT as shown below in figure 9. This wideband coupling method gives results
independent of the application.
The configuration shown in figure 10-a provides a better efficiency in terms of output power and harmonics
rejection. Schematic on figure 10-b gives the equivalent circuit of the pin RFOUT and the DC bias impeder as
well as the matching network components for 434MHz frequency band.
Figure 11 gives the output power versus the R
MOTOROLA
(a)
(b)
Figure 10: Output model and matching network for 434MHz band
1.5pF
RFOUT pin
C
Figure 9: Output power measurement configurations
0
VCC
RFOUT
Freescale Semiconductor, Inc.
250Ω
R
For More Information On This Product,
0
VCC
RFOUT
Go to: www.freescale.com
ext
Impeder: TDK MMZ1608Y102CTA00
Matching
MC33493 Technical Data
Network
39nH
resistor value with 50Ω load and with matching network.
Matching
Network
100pF
L
Impeder: TDK MMZ1608Y102CTA00
1
RF output
Impeder
R
RF output
i
3kΩ
R
L
=50
R
OUTPUT POWER MEASUREMENT
Ω
L
330pF
=50
C
3
Ω
Load
R
L
50Ω
13