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U2741B_05 Datasheet, PDF (8/11 Pages) ATMEL Corporation – UHF ASK/FSK TRANSMITTER
8. Electrical Characteristics (Continued)
All parameters are referred to GND (pin 5). The possible operating ranges refer to different circuit conditions:
VS = 2.0V to 5.5V at Tamb = –20°C to +70°C, VS = 2.2V to 5.5V at Tamb = –40°C to +85°C (typically 25°C, 3V)
Parameters
Test Conditions
Symbol Min.
Typ.
Oscillator frequency XTO
M-version: at Tamb = 25°C
N-version: full temperature range
(monitoring)
Crystal frequency = 13.56 MHz
fXTO
13.56 – 13.56
30 ppm
Crystal frequency = 6.78 MHz
Load capacity of the crystal must be
selected accordingly
fXTO
6.78 – 6.78
30 ppm
Loop bandwidth
Phase noise PLL
Phase noise VCO
Frequency range of the VCO
Clock output
(CMOS microcontroller compatible)
For best LO noise
Loop filter components:
C2 = 3.9 nF, C1 = 15 nF, R4 = 220Ω
Referring to the phase comparator
fPC = 6.78 MHz
at 1 MHz
at 36 MHz
BLoop
PNPLL
PNVCO
PNVCO
fVCO
Clkout
100
–111
–91
–123
300
fout/128
Load capacitance at CLK
Series resonance R of the crystal
FSK modulation frequency rate
fXTO = 13.56 MHz
fXTO = 9.84 MHz
fXTO = 6.78 MHz
fXTO = 4.90 MHz
Duty cycle of the
modulation signal = 50%
CCLK
Rs
Rs
Rs
Rs
fmodFSK
0
ASK modulation frequency rate
Duty cycle of the
modulation signal = 50%
fmodASK
0
CLK output
- Output current Low
- Output current Low
- Output current High
- Output current High
ASK input
- Low level input voltage
- High level input voltage
- Input current High
FSK input
- Low level input voltage
- High level input voltage
- Input current High
VCLK = 0.2 × VS
VCLK = 0.3 × VS
VCLK = 0.8 × VS
VCLK = 0.7 × VS
Iol
Iol
Ioh
Ioh
VASKl
VASKh
IASKh
VFSKl
VFSKh
IFSKh
150
200
–150
–200
1.7
1.7
Max. Unit
13.56 + MHz
30 ppm
6.78 + MHz
30 ppm
kHz
–105 dBC/Hz
–87
–119
450
dBC/Hz
MHz
MHz
10
pF
80
100
150
Ω
225
20
kHz
20
kHz
µA
µA
µA
+100 µA
0.3
V
V
140
µA
0.3
V
V
140
µA
8 U2741B
4733B–RKE–09/05