NXP Semiconductors FXTH870 D Series, Manual

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FXTH870xD
Sensors
162 Freescale Semiconductor, Inc.
17.14 RF Output Stage
1.8

V
DD

3.6, T
L

T
A

T
H
, unless otherwise specified.
Power output based on using Dynamic RF Power Correction firmware routine.
Output load of 50

resistance as shown in Figure 125 unless otherwise specified.
MCU in STOP1 mode during all RF tests.
RF output will shutdown when the total RF I
DD
causes V
DD
to fall below 1.8 V (V
DD
= V
BATT
- I
BATT
x R
BATT
). See Figure 126 .
# Characteristic Symbol Min Typ Max Units
1400
1401
Nominal Output Power with 50

matching network
( note 7 )
315 MHz, T
A
= 25 °C, V
DD
= 3 V, PWR[4:0] = 01110
434 MHz, T
A
= 25 °C, V
DD
= 3 V, PWR[4:0] = 01111
P
RF
P
RF
4.0
3.5 5.2
4.9 6.0
6.0 dBm
dBm
(1)
(1)
(1)
1402*
Nominal Output Power with 50

matching network
at maximum power step, PWR[4:0] = 10100.
Temperature and voltage range defined
by
Figure 123 and Figure 124 . P
RF
3 — — dBm (3)
1403
1404
1405
Programmable Power Adjustment
PWR[4:0] = 00000 through 11111
Low Power Mode (PWR[4:0] = 00000)
Range (nominal, (PWR[4:0] > 00000)
Adjustment step (-1.5 to +8 dBm) P
LPM
P
RF
P
ADJ
—
-1.5
—
-10
—
0.5
—
8.0
—
dBm
dBm
dBm (3)
(3)
(3)
1406
Programmable Frequency Steps
Carrier & FSK Deviation
(AFREQ[12:0] and BFREQ[12:0])
f
STEP
— 3.174 — kHz (3)
1407 External Crystal Frequency ( note 14 ) f
XTAL
— 26.000 — MHz (3)
1408 Fixed portion of RF start process t
S-RCTS
— — 300

sec (3)
1409 Variable portion of RF start process Bits — 3 — bit times (4)
1410
Total RF transmit start time from write of SEND bit to start of
RF @ 2,000 bps,
t
RF
= t
S-RCTS
+ (Bits * bps
-1
)
t
RF2
— — 1.8 msec (3)
1411 Total RF transmit start time from write of SEND bit to start of
RF @ 9,600 bps,
t
RF
= t
S-RCTS
+ (Bits * bps
-1
)
t
RF9.6
— — 613

sec (3)
1412
Total RF transmit start time from write of SEND bit to start of
RF @ 20,000 bps,
t
RF
= t
S-RCTS
+ (Bits * bps
-1
)
t
RF20
— — 450

sec (3)
1413 OOK Modulation Depth M
OOK
50 — — dBc (3)
1414
Manchester Encoding Data Rate
Bit Rate Dependent on accuracy of MFO ( note 18 ) DR — — ±5 % (3)
1415 Modulation Duty-Cycle (OOK and FSK) DC 45 50 55 % (3)
1416 XTAL Oscillator Margin (over 26 MHz) ( note 17 ) ML 600 — —

(4)
1417
1418
Harmonic 2 Level (315 and 434 MHz bands, with matching
reference network)
V
DD
= 3 V, T
A
= 25 °C, PWR[4:0] = 01110
1.8

V
DD

3.6, T
L

T
A

T
H
, power step adjusted to
reach the targeted power in each domain
H2
H2 —
— -35
-25 -22
-20 dBc
dBc (3)
(3)
1419
1420
Harmonic 4 Level and above (315 and 434 MHz bands, with
matching reference network)
V
DD
= 3 V, T
A
= 25 °C, PWR[4:0] = 01110
1.8

V
DD

3.6, T
L

T
A

T
H
, power step adjusted to
reach the targeted power in each domain
H4
H4 —
— —
— -30
-30 dBc
dBc (3)
(3)