U2741B-NFBG3
| Model | U2741B-NFBG3 |
| Description | UHF ASK/FSK TRANSMITTER |
| PDF file | Total 9 pages (File size: 187K) |
| Chip Manufacturer | ATMEL |
U2741B
Electrical Characteristics (Continued)
All parameters are refered to GND (pin 5). The possible operating ranges refer to different circuit conditions:
V
S
= 2.0 V to 5.5 V at T
amb
= -20
°
C to +70
°
C, V
S
= 2.2 V to 5.5 V at T
amb
= -40
°
C to +85
°
C (typically 25
°
C, 3 V)
Parameters
Test Conditions
Symbol
Min.
Typ.
Max.
Unit
M-version: at T
amb
= 25
°
C
N-version: full temperature range
(monitoring)
Crystal frequency = 13.56 MHz
Oscillator frequency XTO
Crystal frequency = 6.78 MHz
Load capacity of the crystal must be
selected accordingly
Loop bandwidth
For best LO noise
Loop filter components:
C
2
= 3.9 nF, C
1
= 15 nF, R
4
= 220
W
Referring to the phase comparator
f
PC
= 6.78 MHz
at 1 MHz
at 36 MHz
f
XTO
13.56 -
30 ppm
6.78 -
30 ppm
13.56
13.56 +
30 ppm
6.78 +
30 ppm
MHz
f
XTO
6.78
MHz
B
Loop
PN
PLL
PN
VCO
PN
VCO
f
VCO
Clk
out
C
CLK
300
100
kHz
Phase noise PLL
Phase noise VCO
Frequency range of the VCO
Clock output
(CMOS microcontroller compatible)
Load capacitance at CLK
-111
-91
-123
-105
-87
-119
450
dBC/Hz
dBC/Hz
MHz
MHz
f
out
/128
10
80
100
150
225
0
0
20
20
pF
W
Series resonance R of the crystal
f
XTO
= 13.56 MHz
f
XTO
= 9.84 MHz
f
XTO
= 6.78 MHz
f
XTO
= 4.90 MHz
Duty cycle of the
modulation signal = 50%
Duty cycle of the
modulation signal = 50%
V
CLK
= 0.2
´
V
S
V
CLK
= 0.3
´
V
S
V
CLK
= 0.8
´
V
S
V
CLK
= 0.7
´
V
S
Rs
Rs
Rs
Rs
f
modFSK
f
modASK
I
ol
I
ol
I
oh
I
oh
V
ASKl
V
ASKh
I
ASKh
V
FSKl
V
FSKh
I
FSKh
FSK modulation frequency rate
ASK modulation frequency rate
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
kHz
kHz
150
200
-150
-200
100
0.3
µA
µA
µA
µA
V
V
µA
V
V
µA
1.7
140
0.3
1.7
140
7
4733A–RKE–11/03
