MAXIM MAX7030HATJ+

19-3706; Rev 2; 6/09
Low-Cost, 315MHz, 345MHz, and 433.92MHz
ASK Transceiver with Fractional-N PLL
Features
The MAX7030 crystal-based, fractional-N transceiver is
designed to transmit and receive ASK/OOK data at factory-preset carrier frequencies of 315MHz, 345MHz†, or
433.92MHz with data rates up to 33kbps (Manchester
encoded) or 66kbps (NRZ encoded). This device generates a typical output power of +10dBm into a 50Ω
load, and exhibits typical sensitivity of -114dBm. The
MAX7030 features separate transmit and receive pins
(PAOUT and LNAIN) and provides an internal RF switch
that can be used to connect the transmit and receive
pins to a common antenna.
o +2.1V to +3.6V or +4.5V to +5.5V Single-Supply
Operation
The MAX7030 transmit frequency is generated by a 16bit, fractional-N, phase-locked loop (PLL), while the
receiver’s local oscillator (LO) is generated by an integer-N PLL. This hybrid architecture eliminates the need
for separate transmit and receive crystal reference
oscillators because the fractional-N PLL is preset to be
10.7MHz above the receive LO. Retaining the fixed-N
PLL for the receiver avoids the higher current-drain
requirements of a fractional-N PLL and keeps the
receiver current drain as low as possible. All frequencygeneration components are integrated on-chip, and
only a crystal, a 10.7MHz IF filter, and a few discrete
components are required to implement a complete
antenna/digital data solution.
o Integrated Transmit and Receive PLL, VCO, and
Loop Filter
The MAX7030 is available in a small, 5mm x 5mm, 32pin thin QFN package, and is specified to operate over
the automotive -40°C to +125°C temperature range.
*0.2% BER, 4kbps Manchester-encoded data, 280kHz IF BW
o Single-Crystal Transceiver
o Factory-Preset Frequency (No Serial Interface
Required)
o ASK/OOK Modulation
o +10dBm Output Power into 50Ω Load
o Integrated TX/RX Switch
o > 45dB Image Rejection
o Typical RF Sensitivity*: -114dBm
o Selectable IF Bandwidth with External Filter
o < 12.5mA Transmit-Mode Current
o < 6.7mA Receive-Mode Current
o < 800nA Shutdown Current
o Fast-On Startup Feature, < 250µs
o Small, 32-Pin, Thin QFN Package
†Consult factory for availability.
Ordering Information
Applications
2-Way Remote Keyless Entry
Security Systems
Home Automation
Remote Controls
Remote Sensing
PART
TEMP RANGE
MAX7030_ATJ+
-40°C to +125°C
PIN-PACKAGE
32 Thin QFN-EP**
+Denotes a lead(Pb)-free/RoHS-compliant package.
**EP = Exposed pad.
Note: The MAX7030 is available with factory-preset operating
frequencies. See the Product Selector Guide for complete part
numbers.
Smoke Alarms
Product Selector Guide
Garage Door Openers
Local Telemetry Systems
PART
CARRIER FREQUENCY (MHz)
MAX7030LATJ+
315
MAX7030MATJ+†
345
MAX7030HATJ+
433.92
†Contact factory for availability.
Pin Configuration, Typical Application Circuit, and
Functional Diagram appear at end of data sheet.
________________________________________________________________ Maxim Integrated Products
For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,
or visit Maxim’s website at www.maxim-ic.com.
1
MAX7030
General Description
MAX7030
Low-Cost, 315MHz, 345MHz, and 433.92MHz
ASK Transceiver with Fractional-N PLL
ABSOLUTE MAXIMUM RATINGS
HVIN to GND..........................................................-0.3V to +6.0V
PAVDD, AVDD, DVDD to GND ................................-0.3V to +4.0V
ENABLE, T/R, DATA, AGC0, AGC1,
AGC2 to GND .......................................-0.3V to (HVIN + 0.3V)
All Other Pins to GND ...............................-0.3V to (_VDD + 0.3V)
Continuous Power Dissipation (TA = +70°C)
32-Pin Thin QFN (derate 21.3mW/°C
above +70°C).............................................................1702mW
Operating Temperature Range .........................-40°C to +125°C
Storage Temperature Range .............................-65°C to +150°C
Lead Temperature (soldering, 10s) .................................+300°C
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.
DC ELECTRICAL CHARACTERISTICS
(Typical Application Circuit, 50Ω system impedance, AVDD = DVDD = HVIN = PAVDD = +2.1V to +3.6V, fRF = 315MHz, 345MHz, or
433.92MHz, TA = -40°C to +125°C, unless otherwise noted. Typical values are at AVDD = DVDD = HVIN = PAVDD = +2.7V, TA = +25°C,
unless otherwise noted.) (Note 1)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
Supply Voltage (3V Mode)
VDD
HVIN, PAVDD, AVDD, and DVDD connected
to power supply
2.1
2.7
3.6
V
Supply Voltage (5V Mode)
HVIN
PAVDD, AVDD, and DVDD unconnected
from HVIN, but connected together
4.5
5.0
5.5
V
Supply Current
IDD
Transmit mode, PA off,
VDATA at 0% duty
cycle (Note 2)
fRF = 315MHz
3.5
5.4
fRF = 434MHz
4.3
6.7
Transmit mode, VDATA
at 50% duty cycle
(Notes 3, 4)
fRF = 315MHz
7.6
12.3
fRF = 434MHz
8.4
13.6
Transmit mode, VDATA
at 100% duty cycle
(Note 2)
fRF = 315MHz
11.6
19.1
fRF = 434MHz
12.4
20.4
Receiver 315MHz
6.1
7.9
Receiver 434MHz
6.4
8.3
Deep-sleep
(3V mode)
0.8
8.8
Deep-sleep
(5V mode)
2.4
10.9
Receiver 315MHz
6.4
8.2
Receiver 434MHz
6.7
8.4
Deep-sleep
(3V mode)
8.0
34.2
Deep-sleep
(5V mode)
14.9
39.3
TA < +85°C,
typ at +25°C
(Note 4)
TA < +125°C,
typ at +125°C
(Note 2)
Voltage Regulator
VREG
mA
µA
mA
µA
HVIN = 5V, ILOAD = 15mA
3.0
V
DIGITAL I/O
Input-High Threshold
VIH
(Note 2)
Input-Low Threshold
VIL
(Note 2)
2
0.9 x
HVIN
_______________________________________________________________________________________
V
0.1 x
HVIN
V
Low-Cost, 315MHz, 345MHz, and 433.92MHz
ASK Transceiver with Fractional-N PLL
(Typical Application Circuit, 50Ω system impedance, AVDD = DVDD = HVIN = PAVDD = +2.1V to +3.6V, fRF = 315MHz, 345MHz, or
433.92MHz, TA = -40°C to +125°C, unless otherwise noted. Typical values are at AVDD = DVDD = HVIN = PAVDD = +2.7V, TA = +25°C,
unless otherwise noted.) (Note 1)
PARAMETER
SYMBOL
Pulldown Sink Current
CONDITIONS
MIN
AGC0-2, ENABLE, T/R, DATA (HVIN = 5.5V)
Output-Low Voltage
VOL
ISINK = 500µA
Output-High Voltage
VOH
ISOURCE = 500µA
TYP
MAX
20
UNITS
µA
0.15
V
HVIN - 0.26
V
AC ELECTRICAL CHARACTERISTICS
(Typical Application Circuit, 50Ω system impedance, PAVDD = AVDD = DVDD = HVIN = +2.1V to +3.6V, fRF = 315MHz, 345MHz, or
433.92MHz, TA = -40°C to +125°C, unless otherwise noted. Typical values are at PAVDD = AVDD = DVDD = HVIN = +2.7V, TA = +25°C,
unless otherwise noted.) (Note 1)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
GENERAL CHARACTERISTICS
Frequency Range
Maximum Input Level
PRFIN
Transmit Efficiency 100% Duty
Cycle
Transmit Efficiency 50% Duty
Cycle
Power-On Time
tON
315/345/
433.92
MHz
0
dBm
fRF = 315MHz (Note 6)
32
fRF = 434MHz (Note 6)
30
fRF = 315MHz (Note 6)
24
fRF = 434MHz (Note 6)
22
ENABLE or T/R transition low to high,
transmitter frequency settled to within
50kHz of the desired carrier
200
ENABLE or T/R transition low to high,
transmitter frequency settled to within 5kHz
of the desired carrier
350
ENABLE transition low to high, or T/R
transition high to low, receiver startup time
(Note 5)
250
%
%
µs
RECEIVER
0.2% BER, 4kbps Manchester
data rate, 280kHz IF BW,
average RF power
Sensitivity
315MHz
-114
434MHz
-113
dBm
Image Rejection
46
dB
POWER AMPLIFIER
Output Power
POUT
TA = +25°C (Note 4)
TA = +125°C, PAVDD = AVDD = DVDD =
HVIN = +2.1V (Note 2)
TA = -40°C, PAVDD = AVDD = DVDD =
HVIN = +3.6V (Note 4)
Modulation Depth
Maximum Carrier Harmonics
Reference Spur
With output-matching network
4.6
10.0
3.9
6.7
13.1
15.5
dBm
15.8
82
dB
-40
dBc
-50
dBc
_______________________________________________________________________________________
3
MAX7030
DC ELECTRICAL CHARACTERISTICS (continued)
MAX7030
Low-Cost, 315MHz, 345MHz, and 433.92MHz
ASK Transceiver with Fractional-N PLL
AC ELECTRICAL CHARACTERISTICS (continued)
(Typical Application Circuit, 50Ω system impedance, PAVDD = AVDD = DVDD = HVIN = +2.1V to +3.6V, fRF = 315MHz, 345MHz, or
433.92MHz, TA = -40°C to +125°C, unless otherwise noted. Typical values are at PAVDD = AVDD = DVDD = HVIN = +2.7V, TA = +25°C,
unless otherwise noted.) (Note 1)
PARAMETER
PHASE-LOCKED LOOP
Transmit VCO Gain
SYMBOL
CONDITIONS
KVCO
Transmit PLL Phase Noise
MIN
TYP
340
10kHz offset, 200kHz loop BW
-68
1MHz offset, 200kHz loop BW
-98
Receive VCO Gain
340
Receive PLL Phase Noise
Loop Bandwidth
10kHz offset, 500kHz loop BW
-80
1MHz offset, 500kHz loop BW
-90
Transmit PLL
200
Receive PLL
500
Reference Frequency Input Level
0.5
MAX
UNITS
MHz/V
dBc/Hz
MHz/V
dBc/Hz
kHz
VP-P
LOW-NOISE AMPLIFIER/MIXER (Note 8)
LNA Input Impedance
ZINLNA
Normalized to 50Ω
High-gain state
Voltage-Conversion Gain
Low-gain state
Input-Referred, 3rd-Order
Intercept Point
IIP3
fRF = 315MHz
1 - j4.7
fRF = 434MHz
1- j3.3
fRF = 315MHz
50
fRF = 434MHz
45
fRF = 315MHz
13
fRF = 434MHz
dB
9
High-gain state
-42
Low-gain state
-6
dBm
Mixer-Output Impedance
330
Ω
LO Signal Feedthrough to
Antenna
-100
dBm
330
Ω
RSSI
Input Impedance
Operating Frequency
10.7
MHz
3dB Bandwidth
fIF
10
MHz
Gain
15
mV/dB
Maximum Data-Filter Bandwidth
50
kHz
Maximum Data-Slicer Bandwidth
100
kHz
Maximum Peak-Detector
Bandwidth
50
kHz
ANALOG BASEBAND
Maximum Data Rate
4
Manchester coded
33
Nonreturn to zero (NRZ)
66
_______________________________________________________________________________________
kbps
Low-Cost, 315MHz, 345MHz, and 433.92MHz
ASK Transceiver with Fractional-N PLL
(Typical Application Circuit, 50Ω system impedance, PAVDD = AVDD = DVDD = HVIN = +2.1V to +3.6V, fRF = 315MHz, 345MHz, or
433.92MHz, TA = -40°C to +125°C, unless otherwise noted. Typical values are at PAVDD = AVDD = DVDD = HVIN = +2.7V, TA = +25°C,
unless otherwise noted.) (Note 1)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
CRYSTAL OSCILLATOR
Crystal Frequency
fXTAL
(fRF -10.7)
/24
MHz
50
mH
2
ppm/V
4.5
pF
Maximum Crystal Inductance
Frequency Pulling by VDD
Crystal Load Capacitance
Note 1:
Note 2:
Note 3:
Note 4:
Note 5:
Note 6:
Note 7:
Note 8:
(Note 7)
Supply current, output power, and efficiency are greatly dependent on board layout and PAOUT match.
100% tested at TA = +125°C. Guaranteed by design and characterization overtemperature.
50% duty cycle at 10kHz ASK data (Manchester coded).
Guaranteed by design and characterization. Not production tested.
Time for final signal detection; does not include baseband filter settling.
Efficiency = POUT/(VDD x IDD).
Dependent on PCB trace capacitance.
Input impedance is measured at the LNAIN pin. Note that the impedance at 315MHz includes the 12nH
inductive degeneration from the LNA source to ground. The impedance at 434MHz includes a 10nH inductive degeneration connected from the LNA source to ground. The equivalent input circuit is 50Ω in series
with ~2.2pF. The voltage conversion is measured with the LNA input-matching inductor, the degeneration
inductor, and the LNA/mixer tank in place, and does not include the IF filter insertion loss.
Typical Operating Characteristics
(Typical Application Circuit, PAVDD = AVDD = DVDD = HVIN = +3.0V, fRF = 433.92MHz, IF BW = 280kHz, 4kbps Manchester encoded,
0.2% BER, TA = +25°C, unless otherwise noted.)
RECEIVER
6.6
+85°C
6.4
6.2
+25°C
6.0
6.6
6.5
+85°C
6.4
6.1
5.6
6.0
2.7
3.0
SUPPLY VOLTAGE (V)
+25°C
6.3
5.8
2.4
3.3
3.6
-40°C
18
MAX7030 toc03
+125°C
6.2
-40°C
2.1
MAX7030 toc02
6.7
SUPPLY CURRENT (mA)
SUPPLY CURRENT (mA)
MAX7030 toc01
+125°C
6.8
DEEP-SLEEP CURRENT vs. TEMPERATURE
SUPPLY CURRENT vs. RF FREQUENCY
6.8
16
DEEP-SLEEP CURRENT (µA)
SUPPLY CURRENT vs. SUPPLY VOLTAGE
7.0
14
VCC = +3.6V
12
VCC = +3.0V
10
VCC = +2.1V
8
6
4
2
0
300
325
350
375
400
RF FREQUENCY (MHz)
425
450
-40
-15
-10
35
60
85
110
TEMPERATURE (°C)
_______________________________________________________________________________________
5
MAX7030
AC ELECTRICAL CHARACTERISTICS (continued)
Low-Cost, 315MHz, 345MHz, and 433.92MHz
ASK Transceiver with Fractional-N PLL
MAX7030
Typical Operating Characteristics (continued)
(Typical Application Circuit, PAVDD = AVDD = DVDD = HVIN = +3.0V, fRF = 433.92MHz, IF BW = 280kHz, 4kbps Manchester encoded,
0.2% BER, TA = +25°C, unless otherwise noted.)
RECEIVER
BIT-ERROR RATE
vs. AVERAGE INPUT POWER
1.6
1.4
fRF = 434MHz
1
0.2% BER
-111
1.0
0.8
AGC SWITCH
POINT
0.6
-114
fRF = 315MHz
0.4
LOW-GAIN MODE
-117
0.2
AGC HYSTERESIS: 3dB
0
-120
-115
-113
-111
-40
-15
50
2.5
40
1.5
30
1.2
0.5
0.9
-0.5
-1.5
DELTA
0.3
0
-90
-70
-50
-30
-10
DELTA (%)
RSSI
3.5
SYSTEM GAIN (dBm)
1.8
0.6
-130 -110
110
10
-10
-3.5
-20
10
-50
-30
48
fRF = 433MHz
46
44
42
5
10
15
20
25
30
-40
-15
10
35
60
85
IF FREQUENCY (MHz)
TEMPERATURE (°C)
S11 vs. RF FREQUENCY
S11 SMITH PLOT OF RFIN
MAX7030 toc11
0
S11 (dB)
433MHz
-12
433.92MHz
-12
-18
-16
-20
400MHz
-24
1
10
IF FREQUENCY (MHz)
100
10
fRF = 315MHz
-6
-8
-10
LOWER SIDEBAND
0
MAX7030 toc10
-70
IMAGE REJECTION vs. TEMPERATURE
0
-2.5
-90
RF INPUT POWER (dBm)
FROM RFIN
TO MIXOUT
fRF = 434MHz
48dB IMAGE
REJECTION
20
NORMALIZED IF GAIN vs. IF FREQUENCY
-4
85
UPPER SIDEBAND
IF INPUT POWER (dBm)
0
60
SYSTEM GAIN vs. IF FREQUENCY
MAX7030 toc07
1.5
35
TEMPERATURE (°C)
RSSI AND DELTA vs. IF INPUT POWER
2.1
10
MAX7030 toc09
-117
AVERAGE INPUT POWER (dBm)
IMAGE REJECTION (dB)
-119
MAX7030 toc08
-121
200
250
300
350
400
450
110
MAX7030 toc12
0.01
6
HIGH-GAIN MODE
1.2
fRF = 434MHz
RSSI (V)
SENSITIVITY (dBm)
BIT-ERROR RATE (%)
10
-108
MAX7030 toc06
-105
fRF = 315MHz
RSSI (V)
1.8
MAX7030 toc05
MAX7030 toc04
-102
0.1
NORMALIZED IF GAIN (dB)
RSSI vs. RF INPUT POWER
SENSITIVITY vs. TEMPERATURE
100
500
RF FREQUENCY (MHz)
_______________________________________________________________________________________
500MHz
Low-Cost, 315MHz, 345MHz, and 433.92MHz
ASK Transceiver with Fractional-N PLL
RECEIVER
INPUT IMPEDANCE
vs. INDUCTIVE DEGENERATION
INPUT IMPEDANCE
vs. INDUCTIVE DEGENERATION
-220
90
-230
80
MAX7030 toc14
-240
60
-250
50
-260
40
-270
REAL IMPEDANCE
20
1
IMAGINARY
IMPEDANCE
70
-180
50
-190
40
-200
-280
30
-290
20
REAL IMPEDANCE
-220
MAX7030 toc15
fRF = 315MHz
PHASE NOISE vs. OFFSET FREQUENCY
-50
-70
-80
-90
-100
-110
fRF = 433MHz
-60
PHASE NOISE (dBc/Hz)
PHASE NOISE (dBc/Hz)
100
INDUCTIVE DEGENERATION (nH)
PHASE NOISE vs. OFFSET FREQUENCY
-60
-210
10
1
INDUCTIVE DEGENERATION (nH)
-50
-170
60
100
10
-160
MAX7030 toc16
30
REAL IMPEDANCE (Ω)
REAL IMPEDANCE (Ω)
IMAGINARY
IMPEDANCE
70
IMAGINARY IMPEDANCE (Ω)
fRF = 315MHz
80
-150
fRF = 434MHz
IMAGINARY IMPEDANCE (Ω)
MAX7030 toc13
90
-70
-80
-90
-100
-110
-120
-120
100
1k
10k
100k
OFFSET FREQUENCY (Hz)
1M
10M
100
1k
10k
100k
1M
10M
OFFSET FREQUENCY (Hz)
_______________________________________________________________________________________
7
MAX7030
Typical Operating Characteristics (continued)
(Typical Application Circuit, PAVDD = AVDD = DVDD = HVIN = +3.0V, fRF = 433.92MHz, IF BW = 280kHz, 4kbps Manchester encoded,
0.2% BER, TA = +25°C, unless otherwise noted.)
Typical Operating Characteristics (continued)
(Typical Application Circuit, PAVDD = AVDD = DVDD = HVIN = +3.0V, fRF = 433.92MHz, IF BW = 280kHz, 4kbps Manchester encoded,
0.2% BER, TA = +25°C, unless otherwise noted.)
TRANSMITTER
SUPPLY CURRENT
vs. SUPPLY VOLTAGE
TA = +85°C
TA = +125°C
TA = -40°C
TA = +25°C
10
5.0
TA = +125°C
4.5
TA = +85°C
4.0
3.5
3.0
3.0
2.4
TA = +125°C
5.0
TA = +85°C
4.5
4.0
3.0
3.3
3.6
2.1
TA = +25°C
10
9
PA ON
8
7
TA = -40°C
3.0
2.4
2.7
3.0
3.3
3.6
-6
-2
2
MAX7030 toc23-1
POWER
14
12
4
10
0
SUPPLY CURRENT (mA)
CURRENT
-10
2
16
12
8
4
CURRENT
-8
-12
4
-16
2
10k
POWER
-4
6
1k
MAX7030 toc23-2
8
-8
100
-2
0
6
fRF = 315MHz
PA ON
-6
-12
fRF = 433MHz
PA ON
-16
0.1
6
AVERAGE OUTPUT POWER (dBm)
10
-4
10
MAX7030 toc19
50% DUTY CYCLE
-14
10
6
12
8
EXTERNAL RESISTOR (Ω)
8
SUPPLY CURRENT (mA)
8
OUTPUT POWER (dBm)
14
1
8
18
16
16
0.1
9
SUPPLY CURRENT AND OUTPUT POWER
vs. EXTERNAL RESISTOR
12
2
PA ON
10
AVERAGE OUTPUT POWER (dBm)
SUPPLY CURRENT AND OUTPUT POWER
vs. EXTERNAL RESISTOR
4
11
5
-10
SUPPLY VOLTAGE (V)
16
3.6
6
-14
18
3.3
12
7
4
2.1
3.0
fRF = 434MHz
PA ON
ENVELOPE SHAPING ENABLED
13
50% DUTY CYCLE
5
2.7
SUPPLY CURRENT vs. OUTPUT POWER
14
6
3.5
2.4
SUPPLY VOLTAGE (V)
fRF = 315MHz
PA ON
ENVELOPE SHAPING ENABLED
11
SUPPLY CURRENT (mA)
fRF = 434MHz
PA OFF
5.5
2.7
SUPPLY CURRENT vs. OUTPUT POWER
12
MAX7030 toc20
6.0
TA = +25°C
SUPPLY VOLTAGE (V)
SUPPLY VOLTAGE (V)
SUPPLY CURRENT
vs. SUPPLY VOLTAGE
TA = -40°C
TA = +125°C
13
9
2.1
3.6
3.3
SUPPLY CURRENT (mA)
2.7
MAX7030 toc21
2.4
TA = +85°C
TA = -40°C
TA = +25°C
2.0
2.1
15
11
2.5
8
fRF = 434MHz
PA ON
WITHOUT ENVELOPE SHAPING
MAX7030 toc22
14
12
fRF = 315MHz
PA OFF
5.5
1
10
100
1k
10k
EXTERNAL RESISTOR (Ω)
_______________________________________________________________________________________
OUTPUT POWER (dBm)
fRF = 315MHz
PA ON
WITHOUT ENVELOPE SHAPING
SUPPLY CURRENT vs. SUPPLY VOLTAGE
17
SUPPLY CURRENT (mA)
MAX7030 toc17
6.0
SUPPLY CURRENT (mA)
SUPPLY CURRENT (mA)
16
MAX7030 toc18
SUPPLY CURRENT vs. SUPPLY VOLTAGE
SUPPLY CURRENT (mA)
MAX7030
Low-Cost, 315MHz, 345MHz, and 433.92MHz
ASK Transceiver with Fractional-N PLL
10
Low-Cost, 315MHz, 345MHz, and 433.92MHz
ASK Transceiver with Fractional-N PLL
TRANSMITTER
TA = +125°C
TA = +85°C
6
8
TA = +125°C
TA = +85°C
6
2.7
3.0
3.3
2.4
OUTPUT POWER vs. SUPPLY VOLTAGE
3.0
MAX7030 25-2
fRF = 434MHz
PA ON
ENVELOPE SHAPING ENABLED
12
fRF = 315MHz
PA ON
2.1
3.6
2.4
TA = -40°C
TA = +25°C
10
MAX7030 25-1
3.3
3.6
fRF = 434MHz
PA ON
TA = -40°C
35
TA = +85°C
25
TA = +125°C
3.0
EFFICIENCY vs. SUPPLY VOLTAGE
40
TA = +25°C
30
2.7
SUPPLY VOLTAGE (V)
TA = -40°C
35
8
3.3
EFFICIENCY vs. SUPPLY VOLTAGE
40
EFFICIENCY (%)
OUTPUT POWER (dBm)
2.7
SUPPLY VOLTAGE (V)
SUPPLY VOLTAGE (V)
14
TA = +125°C
TA = +85°C
4
2.1
3.6
EFFICIENCY (%)
2.4
MAX7030 toc26
2.1
8
6
4
4
10
MAX7030 toc27
8
TA = +25°C
10
fRF = 434MHz
PA ON
ENVELOPE SHAPING DISABLED
TA = -40°C
TA = +25°C
12
OUTPUT POWER (dBm)
10
fRF = 315MHz
PA ON
ENVELOPE SHAPING ENABLED
TA = -40°C
12
OUTPUT POWER (dBm)
OUTPUT POWER (dBm)
TA = -40°C
TA = +25°C
14
MAX7030 24-2
fRF = 315MHz
PA ON
ENVELOPE SHAPING DISABLED
12
14
MAX7030 24-1
14
OUTPUT POWER vs. SUPPLY VOLTAGE
OUTPUT POWER vs. SUPPLY VOLTAGE
OUTPUT POWER vs. SUPPLY VOLTAGE
TA = +25°C
TA = +85°C
30
25
TA = +125°C
TA = +125°C
TA = +85°C
20
20
2.7
3.0
3.3
2.1
3.6
2.4
SUPPLY VOLTAGE (V)
TA = -40°C
EFFICIENCY (%)
EFFICIENCY (%)
3.3
TA = +25°C
20
TA = +85°C TA = +125°C
fRF = 434MHz
50% DUTY CYCLE
25
TA = +25°C
20
2.7
3.0
3.3
3.6
3.3
3.6
-40
fRF = 315MHz
-50
-60
-70
-80
-90
-100
-110
-130
15
SUPPLY VOLTAGE (V)
3.0
-120
TA = +125°C
10
2.7
PHASE NOISE vs. OFFSET FREQUENCY
TA = +85°C
2.4
2.4
SUPPLY VOLTAGE (V)
TA = -40°C
15
2.1
2.1
3.6
EFFICIENCY vs. SUPPLY VOLTAGE
30
MAX7030 toc28
fRF = 315MHz
50% DUTY CYCLE
25
3.0
SUPPLY VOLTAGE (V)
EFFICIENCY vs. SUPPLY VOLTAGE
30
2.7
PHASE NOISE (dBc/Hz)
2.4
MAX7030 toc29
2.1
MAX7030 toc30
6
-140
2.1
2.4
2.7
3.0
SUPPLY VOLTAGE (V)
3.3
3.6
100
1k
10k
100k
1M
10M
OFFSET FREQUENCY (Hz)
_______________________________________________________________________________________
9
MAX7030
Typical Operating Characteristics (continued)
(Typical Application Circuit, PAVDD = AVDD = DVDD = HVIN = +3.0V, fRF = 433.92MHz, IF BW = 280kHz, 4kbps Manchester encoded,
0.2% BER, TA = +25°C, unless otherwise noted.)
Typical Operating Characteristics (continued)
(Typical Application Circuit, PAVDD = AVDD = DVDD = HVIN = +3.0V, fRF = 433.92MHz, IF BW = 280kHz, 4kbps Manchester encoded,
0.2% BER, TA = +25°C, unless otherwise noted.)
TRANSMITTER
REFERENCE SPUR MAGNITUDE
vs. SUPPLY VOLTAGE
PHASE NOISE vs. OFFSET FREQUENCY
-70
-80
-90
-100
-110
-120
-45
MAX7030 toc32
-60
REFERENCE SPUR MAGNITUDE (dBc)
fRF = 434MHz
-50
-40
MAX7030 toc31
-40
PHASE NOISE (dBc/Hz)
434MHz
-50
315MHz
-55
-60
-65
-130
-70
-140
100
1k
10k
100k
1M
2.1
10M
2.4
2.7
3.0
SUPPLY VOLTAGE (V)
OFFSET FREQUENCY (Hz)
FREQUENCY STABILITY
vs. SUPPLY VOLTAGE
MAX7030 toc33
10
8
FREQUENCY STABILITY (ppm)
MAX7030
Low-Cost, 315MHz, 345MHz, and 433.92MHz
ASK Transceiver with Fractional-N PLL
6
fRF = 434MHz
4
2
0
-2
fRF = 315MHz
-4
-6
-8
-10
2.1
2.4
2.7
3.0
3.3
3.6
SUPPLY VOLTAGE (V)
10
______________________________________________________________________________________
3.3
3.6
Low-Cost, 315MHz, 345MHz, and 433.92MHz
ASK Transceiver with Fractional-N PLL
PIN
NAME
FUNCTION
1
PAVDD
Power-Amplifier Supply Voltage. Bypass to GND with 0.01µF and 220pF capacitors placed as close
as possible to the pin.
2
ROUT
Envelope-Shaping Output. ROUT controls the power-amplifier envelope’s rise and fall times. Connect
ROUT to the PA pullup inductor or optional power-adjust resistor. Bypass the inductor to GND as
close as possible to the inductor with 680pF and 220pF capacitors, as shown in the Typical
Application Circuit.
3
TX/RX1
Transmit/Receive Switch Throw. Drive T/R high to short TX/RX1 to TX/RX2. Drive T/R low to disconnect
TX/RX1 from TX/RX2. Functionally identical to TX/RX2.
4
TX/RX2
Transmit/Receive Switch Pole. Typically connected to ground. See the Typical Application Circuit.
5
PAOUT
Power-Amplifier Output. Requires a pullup inductor to the supply voltage (or ROUT if envelope
shaping is desired), which can be part of the output-matching network to an antenna.
6
AVDD
7
LNAIN
Analog Power-Supply Voltage. AVDD is connected to an on-chip +3.0V regulator in 5V operation.
Bypass AVDD to GND with a 0.1µF and 220pF capacitor placed as close as possible to the pin.
Low-Noise Amplifier Input. Must be AC-coupled.
8
LNASRC
Low-Noise Amplifier Source for External Inductive Degeneration. Connect an inductor to GND to set
the LNA input impedance.
9
LNAOUT
Low-Noise Amplifier Output. Must be connected to AVDD through a parallel LC tank filter. AC-couple
to MIXIN+.
10
MIXIN+
Noninverting Mixer Input. Must be AC-coupled to the LNA output.
11
MIXIN-
Inverting Mixer Input. Bypass to AVDD with a capacitor as close as possible to the LNA LC tank filter.
12
MIXOUT
330Ω Mixer Output. Connect to the input of the 10.7MHz filter.
13
14
15
16
17
18
19
20
21, 25
IFINIFIN+
PDMIN
PDMAX
DSDS+
OP+
DF
N.C.
Inverting 330Ω IF Limiter-Amplifier Input. Bypass to GND with a capacitor.
Noninverting 330Ω IF Limiter-Amplifier Input. Connect to the output of the 10.7MHz IF filter.
Minimum-Level Peak Detector for Demodulator Output
Maximum-Level Peak Detector for Demodulator Output
Inverting Data Slicer Input
Noninverting Data Slicer Input
Noninverting Op-Amp Input for the Sallen-Key Data Filter
Data-Filter Feedback Node. Input for the feedback capacitor of the Sallen-Key data filter.
No Connection. Do not connect to this pin.
22
T/R
Transmit/Receive. Drive high to put the device in transmit mode. Drive low or leave unconnected to
put the device in receive mode. It is internally pulled down.
23
ENABLE
Enable. Drive high for normal operation. Drive low or leave unconnected to put the device into shutdown mode.
24
DATA
Receiver Data Output/Transmitter Data Input
26
DVDD
Digital Power-Supply Voltage. Bypass to GND with a 0.01µF and 220pF capacitor placed as close as
possible to the pin.
27
HVIN
High-Voltage Supply Input. For 3V operation, connect HVIN to AVDD, DVDD, and PAVDD. For 5V
operation, connect only HVIN to 5V. Bypass HVIN to GND with a 0.01µF and 220pF capacitor placed
as close as possible to the pin.
______________________________________________________________________________________
11
MAX7030
Pin Description
Low-Cost, 315MHz, 345MHz, and 433.92MHz
ASK Transceiver with Fractional-N PLL
MAX7030
Pin Description (continued)
PIN
NAME
28
AGC2
AGC Enable/Dwell Time Control 2 (MSB). See Table 1. Bypass to GND with a 10pF capacitor.
FUNCTION
29
AGC1
AGC Enable/Dwell Time Control 1. See Table 1. Bypass to GND with a 10pF capacitor.
30
AGC0
AGC Enable/Dwell Time Control 0 (LSB). See Table 1. Bypass to GND with a 10pF capacitor.
31
XTAL1
Crystal Input 1. Bypass to GND if XTAL2 is driven by an AC-coupled external reference.
32
XTAL2
Crystal Input 2. XTAL2 can be driven from an external AC-coupled reference.
—
EP
Exposed Pad. Solder evenly to the board’s ground plane for proper operation.
Detailed Description
The MAX7030 315MHz, 345MHz, and 433.92MHz
CMOS transceiver and a few external components provide a complete transmit and receive chain from the
antenna to the digital data interface. This device is
designed for transmitting and receiving ASK data. All
transmit frequencies are generated by a fractional-Nbased synthesizer, allowing for very fine frequency
steps in increments of fXTAL/4096. The receive LO is
generated by a traditional integer-N-based synthesizer.
Depending on component selection, data rates as high
as 33kbps (Manchester encoded) or 66kbps (NRZ
encoded) can be achieved.
Receiver
Low-Noise Amplifier (LNA)
The LNA is a cascode amplifier with off-chip inductive
degeneration that achieves approximately 30dB of voltage gain that is dependent on both the antenna-matching network at the LNA input and the LC tank network
between the LNA output and the mixer inputs.
The off-chip inductive degeneration is achieved by
connecting an inductor from LNASRC to GND. This
inductor sets the real part of the input impedance at
LNAIN, allowing for a more flexible match for low-input
impedances such as a PCB trace antenna. A nominal
value for this inductor with a 50Ω input impedance is
12nH at 315MHz and 10nH at 434MHz, but the inductance is affected by PCB trace length. LNASRC can be
shorted to ground to increase sensitivity by approximately 1dB, but the input match must then be reoptimized.
12
The LC tank filter connected to LNAOUT consists of L5
and C9 (see the Typical Application Circuit). Select L5
and C9 to resonate at the desired RF input frequency.
The resonant frequency is given by:
f=
1
2π L TOTAL × C TOTAL
where LTOTAL = L5 + LPARASITICS and CTOTAL = C9 +
CPARASITICS.
LPARASITICS and CPARASITICS include inductance and
capacitance of the PCB traces, package pins, mixerinput impedance, LNA-output impedance, etc. These
parasitics at high frequencies cannot be ignored, and
can have a dramatic effect on the tank filter center frequency. Lab experimentation should be done to optimize the center frequency of the tank. The total
parasitic capacitance is generally between 5pF and
7pF.
Automatic Gain Control (AGC)
When the AGC is enabled, it monitors the RSSI output.
When the RSSI output reaches 1.28V, which corresponds to an RF input level of approximately -55dBm,
the AGC switches on the LNA gain-reduction attenuator. The attenuator reduces the LNA gain by 36dB,
thereby reducing the RSSI output by about 540mV to
740mV. The LNA resumes high-gain mode when the
RSSI output level drops back below 680mV (approximately -59dBm at the RF input) for a programmable
interval called the AGC dwell time (see Table 1). The
AGC has a hysteresis of approximately 4dB. With the
AGC function, the RSSI dynamic range is increased,
allowing the MAX7030 to reliably produce an ASK output for RF input levels up to 0dBm with a modulation
depth of 18dB. AGC is not required and can be disabled (see Table 1).
______________________________________________________________________________________
Low-Cost, 315MHz, 345MHz, and 433.92MHz
ASK Transceiver with Fractional-N PLL
AGC2
AGC1
AGC0
0
0
0
AGC disabled, high gain selected
DESCRIPTION
0
0
1
K = 11
0
1
0
K = 13
0
1
1
K = 15
1
0
0
K = 17
1
0
1
K = 19
1
1
0
K = 21
1
1
1
K = 23
AGC Dwell-Time Settings
The AGC dwell timer holds the AGC in low-gain state
for a set amount of time after the power level drops
below the AGC switching threshold. After that set
amount of time, if the power level is still below the AGC
threshold, the LNA goes into high-gain state. This is
important for ASK since the modulated data may have
a high level above the threshold and low level below
the threshold, which without the dwell timer would
cause the AGC to switch on every bit.
The MAX7030 uses the three AGC control pins (AGC0,
AGC1, AGC2) to set seven user-controlled, dwell-timer
settings. The AGC dwell time is dependent on the crystal frequency and the bit settings of the AGC control
pins. To calculate the dwell time, use the following
equation:
Dwell Time =
2K
fXTAL
where K is an odd integer in decimal from 11 to 23, determined by the control pin settings shown in Table 1.
To calculate the value of K, use the following equation
and use the next integer higher than the calculated
result:
K ≥ 3.3 x log10 (Dwell Time x fXTAL)
For Manchester Code (50% duty cycle), set the dwell
time to at least twice the bit period. For nonreturn-tozero (NRZ) data, set the dwell to greater than the period of the longest string of zeros or ones. For example,
using Manchester Code at 315MHz (f XTAL =
12.679MHz) with a data rate of 2kbps (bit period =
250µs), the dwell time needs to be greater than 500µs:
K ≥ 3.3 x log10 (500µs x 12.679) ≈ 12.546
Choose the AGC pin settings for K to be the next oddinteger value higher than 12.546, which is 13. This says
that AGC1 is set high and AGC0 and AGC2 are set low.
Mixer
A unique feature of the MAX7030 is the integrated
image rejection of the mixer. This eliminates the need
for a costly front-end SAW filter for many applications.
The advantage of not using a SAW filter is increased
sensitivity, simplified antenna matching, less board
space, and lower cost.
The mixer cell is a pair of double-balanced mixers that
perform an IQ downconversion of the RF input to the
10.7MHz intermediate frequency (IF) with low-side
injection (i.e., fLO = fRF - fIF). The image-rejection circuit
then combines these signals to achieve a typical 46dB
of image rejection over the full temperature range. Lowside injection is required as high-side injection is not
possible due to the on-chip image rejection. The IF output is driven by a source follower, biased to create a
driving impedance of 330Ω to interface with an off-chip
330Ω ceramic IF filter. The voltage-conversion gain driving a 330Ω load is approximately 20dB. Note that the
MIXIN+ and MIXIN- inputs are functionally identical.
Integer-N Phase-Locked Loop (PLL)
The MAX7030 utilizes a fixed-integer-N PLL to generate
the receive LO. All PLL components, including the loop
filter, voltage-controlled oscillator, charge pump, asynchronous 24x divider, and phase-frequency detector
are integrated internally. The loop bandwidth is approximately 500kHz. The relationship between RF, IF, and
reference frequencies is given by:
fREF = (fRF - fIF)/24
______________________________________________________________________________________
13
MAX7030
Table 1. AGC Dwell Time Settings for
MAX7030
MAX7030
Low-Cost, 315MHz, 345MHz, and 433.92MHz
ASK Transceiver with Fractional-N PLL
Intermediate Frequency (IF)
The IF section presents a differential 330Ω load to provide matching for the off-chip ceramic filter. The internal
six AC-coupled limiting amplifiers produce an overall
gain of approximately 65dB, with a bandpass filter type
response centered near the 10.7MHz IF frequency with
a 3dB bandwidth of approximately 10MHz. For ASK
data, the RSSI circuit demodulates the IF to baseband
by producing a DC output proportional to the log of the
IF signal level with a slope of approximately 15mV/dB.
Data Filter
The data filter for the demodulated data is implemented
as a 2nd-order, lowpass, Sallen-Key filter. The pole
locations are set by the combination of two on-chip
resistors and two external capacitors. Adjusting the
value of the external capacitors changes the corner frequency to optimize for different data rates. Set the corner frequency in kHz to approximately 3 times the
fastest expected Manchester data rate in kbps from the
transmitter (1.5 times the fastest expected NRZ data
rate). Keeping the corner frequency near the data rate
rejects any noise at higher frequencies, resulting in an
increase in receiver sensitivity.
The configuration shown in Figure 1 can create a
Butterworth or Bessel response. The Butterworth filter
offers a very-flat-amplitude response in the passband
and a rolloff rate of 40dB/decade for the two-pole filter.
The Bessel filter has a linear phase response, which
works well for filtering digital data. To calculate the
value of the capacitors, use the following equations,
along with the coefficients in Table 2:
Data Slicer
The data slicer takes the analog output of the data filter
and converts it to a digital signal. This is achieved by
using a comparator and comparing the analog input to
a threshold voltage. The threshold voltage is set by the
voltage on the DS- pin, which is connected to the negative input of the data slicer comparator.
Numerous configurations can be used to generate the
data-slicer threshold. For example, the circuit in Figure
2 shows a simple method using only one resistor and
one capacitor. This configuration averages the analog
output of the filter and sets the threshold to approximately 50% of that amplitude. With this configuration,
the threshold automatically adjusts as the analog signal
varies, minimizing the possibility for errors in the digital
data. The values of R and C affect how fast the threshold tracks the analog amplitude. Be sure to keep the
corner frequency of the RC circuit much lower (about
10 times) than the lowest expected data rate.
With this configuration, a long string of NRZ zeros or
ones can cause the threshold to drift. This configuration
works best if a coding scheme, such as Manchester
coding, which has an equal number of zeros and ones,
is used.
Figure 3 shows a configuration that uses the positive and
negative peak detectors to generate the threshold. This
configuration sets the threshold to the midpoint between
a high output and a low output of the data filter.
MAX7030
RSSI
b
a(100kΩ)(π)(fc )
a
CF2 =
4(100kΩ)(π)(fc )
CF1 =
100kΩ
100kΩ
DS+
where fC is the desired 3dB corner frequency.
For example, choose a Butterworth filter response with
a corner frequency of 5kHz:
OP+
DF
CF2
CF1
Figure 1. Sallen-Key Lowpass Data Filter
1.000
CF1 =
≈ 450pF
(1.414)(100kΩ)(3.14)(5kHz)
1.414
CF2 =
≈ 225pF
(4)(100kΩ)(3.14)(5kHz)
Choosing standard capacitor values changes CF1 to
470pF and CF2 to 220pF. In the Typical Application Circuit,
CF1 and CF2 are named C16 and C17, respectively.
14
Table 2. Coefficients to Calculate CF1
and CF2
FILTER TYPE
a
b
Butterworth
(Q = 0.707)
1.414
1.000
Bessel
(Q = 0.577)
1.3617
0.618
______________________________________________________________________________________
Low-Cost, 315MHz, 345MHz, and 433.92MHz
ASK Transceiver with Fractional-N PLL
MAX7030
MAX7030
MAX7030
DATA
SLICER
DATA
DS-
DS+
PEAK
DET
PEAK
DET
DATA
SLICER
R
C
DATA
Figure 2. Generating Data-Slicer Threshold Using a Lowpass
Filter
Peak Detectors
The maximum peak detector (PDMAX) and minimum
peak detector (PDMIN), with resistors and capacitors
shown in Figure 3, create DC output voltages equal to
the high- and low-peak values of the filtered demodulated signal. The resistors provide a path for the capacitors to discharge, allowing the peak detectors to
dynamically follow peak changes of the data filter output voltages.
The maximum and minimum peak detectors can be
used together to form a data slicer threshold voltage at
a value midway between the maximum and minimum
voltage levels of the data stream (see the Data Slicer
section and Figure 3). Set the RC time constant of the
peak detector combining network to at least 5 times the
data period.
If there is an event that causes a significant change in
the magnitude of the baseband signal, such as an AGC
gain-switch or a power-up transient, the peak detectors
may “catch” a false level. If a false peak is detected,
the slicing level is incorrect. The MAX7030 peak detectors correct these problems by temporarily tracking the
incoming baseband filter voltage when an AGC state
switch occurs, or forcing the peak detectors to track the
baseband filter output voltage until all internal circuits
are stable following an enable pin low-to-high transition
and also T/R pin high-to-low transition. The peak detectors exhibit a fast attack/slow decay response. This feature allows for an extremely fast startup or AGC
recovery.
Transmitter
Power Amplifier (PA)
The PA of the MAX7030 is a high-efficiency, opendrain, switch-mode amplifier. The PA with proper output- matching network can drive a wide range of
antenna impedances, which includes a small-loop PCB
PDMAX
R
C
PDMIN
R
C
Figure 3. Generating Data-Slicer Threshold Using the Peak
Detectors
trace and a 50Ω antenna. The output-matching network
for a 50Ω antenna is shown in the Typical Application
Circuit. The output-matching network suppresses the
carrier harmonics and transforms the antenna impedance to an optimal impedance at PAOUT (pin 5). The
optimal impedance at PAOUT is 250Ω.
When the output-matching network is properly tuned,
the PA transmits power with a high overall efficiency of
up to 32%. The efficiency of the PA itself is more than
46%. The output power is set by an external resistor at
PAOUT, and is also dependent on the external antenna
and antenna-matching network at the PA output.
Envelope Shaping
The MAX7030 features an internal envelope-shaping
resistor, which connects between the open-drain output
of the PA and the power supply (see the Typical
Application Circuit ). The envelope-shaping resistor
slows the turn-on/turn-off of the PA in ASK mode, and
results in a smaller spectral width of the modulated PA
output signal.
Fractional-N Phase-Locked Loop (PLL)
The MAX7030 utilizes a fully integrated, fractional-N,
PLL for its transmit frequency synthesizer. All PLL components, including the loop filter, are integrated internally. The loop bandwidth is approximately 200kHz.
Power-Supply Connections
The MAX7030 can be powered from a 2.1V to 3.6V supply or a 4.5V to 5.5V supply. If a 4.5V to 5.5V supply is
used, then the on-chip linear regulator reduces the 5V
supply to the 3V needed to operate the chip.
To operate the MAX7030 from a 3V supply, connect
PAVDD, AVDD, DVDD, and HVIN to the 3V supply. When
using a 5V supply, connect the supply to HVIN only and
______________________________________________________________________________________
15
connect AVDD, PAVDD, and DVDD together. In both
cases, bypass DVDD, HVIN, and PAVDD to GND with
0.01µF and 220pF capacitors and bypass AV DD to
GND with 0.1µF and 220pF capacitors. Bypass T/R,
ENABLE, DATA, and AGC0-2 with 10pF capacitors to
GND. Place all bypass capacitors as close as possible
to the respective pins.
Transmit/Receive Antenna Switch
The MAX7030 features an internal SPST RF switch that,
when combined with a few external components, allows
the transmit and receive pins to share a common
antenna (see the Typical Application Circuit). In receive
mode, the switch is open and the power amplifier is
shut down, presenting a high impedance to minimize
the loading of the LNA. In transmit mode, the switch
closes to complete a resonant tank circuit at the PA
output and forms an RF short at the input to the LNA. In
this mode, the external passive components couple the
output of the PA to the antenna and protect the LNA
input from strong transmitted signals.
The switch state is controlled by the T/R pin (pin 22).
Drive T/R high to put the device in transmit mode; drive
T/R low to put the device in receive mode.
In actuality, the oscillator pulls every crystal. The crystal’s natural frequency is really below its specified frequency, but when loaded with the specified load
capacitance, the crystal is pulled and oscillates at its
specified frequency. This pulling is already accounted
for in the specification of the load capacitance.
Additional pulling can be calculated if the electrical
parameters of the crystal are known. The frequency
pulling is given by:
fP =
⎞
Cm ⎛
1
1
−
x 106
⎜
2 ⎝ CCASE + CLOAD
CCASE + CSPEC ⎟⎠
where:
fp is the amount the crystal frequency is pulled in ppm.
Cm is the motional capacitance of the crystal.
CCASE is the case capacitance.
CSPEC is the specified load capacitance.
CLOAD is the actual load capacitance.
When the crystal is loaded as specified, i.e.,
CLOAD = CSPEC, the frequency pulling equals zero.
Crystal Oscillator (XTAL)
Pin Configuration
ENABLE
T/R
N.C.
DF
OP+
DS+
DS-
TOP VIEW
DATA
24
23
22
21
20
19
18
17
N.C.
25
16
PDMAX
DVDD
26
15
PDMIN
HVIN
27
14
IFIN+
13
IFIN-
12
MIXOUT
AGC2
28
AGC1
29
AGC0
30
11
MIXIN-
XTAL1
31
10
MIXIN+
XTAL2
32
9
LNAOUT
4
5
6
7
8
AVDD
LNAIN
LNASRC
3
PAOUT
2
TX/RX2
1
ROUT
+
MAX7030
TX/RX1
The XTAL oscillator in the MAX7030 is designed to present a capacitance of approximately 3pF between the
XTAL1 and XTAL2 pins. In most cases, this corresponds to a 4.5pF load capacitance applied to the
external crystal when typical PCB parasitics are added.
It is very important to use a crystal with a load
capacitance that is equal to the capacitance of the
MAX7030 crystal oscillator plus PCB parasitics. If a
crystal designed to oscillate with a different load
capacitance is used, the crystal is pulled away from its
stated operating frequency, introducing an error in the
reference frequency. Crystals designed to operate with
higher differential load capacitance always pull the reference frequency higher.
PAVDD
MAX7030
Low-Cost, 315MHz, 345MHz, and 433.92MHz
ASK Transceiver with Fractional-N PLL
THIN QFN
16
______________________________________________________________________________________
Low-Cost, 315MHz, 345MHz, and 433.92MHz
ASK Transceiver with Fractional-N PLL
MAX7030
Table 3. Component Values for Typical Application Circuit
COMPONENT
VALUE FOR
433.92MHz RF
VALUE FOR
315MHz RF
DESCRIPTION
C1
220pF
220pF
10%
C2
680pF
680pF
10%
C3
6.8pF
12pF
5%
C4
6.8pF
10pF
5%
C5
10pF
22pF
5%
C6
220pF
220pF
10%
10%
C7
0.1µF
0.1µF
C8
100pF
100pF
5%
C9
1.8pF
2.7pF
±0.1pF
C10
100pF
100pF
5%
C11
220pF
220pF
10%
C12
100pF
100pF
5%
C13
1500pF
1500pF
10%
C14
0.047µF
0.047µF
10%
C15
0.047µF
0.047µF
10%
C16
470pF
470pF
10%
C17
220pF
220pF
10%
C18
220pF
220pF
10%
C19
0.01µF
0.01µF
10%
C20
100pF
100pF
5%
C21
100pF
100pF
5%
C22
220pF
220pF
10%
C23
0.01µF
0.01µF
10%
C24
0.01µF
0.01µF
10%
L1
22nH
27nH
Coilcraft 0603CS
L2
22nH
30nH
Coilcraft 0603CS
L3
22nH
30nH
Coilcraft 0603CS
L4
10nH
12nH
Coilcraft 0603CS
L5
16nH
30nH
Murata LQW18A
L6
68nH
100nH
Coilcraft 0603CS
R1
100kΩ
100kΩ
5%
R2
100kΩ
100kΩ
5%
R3
0Ω
0Ω
—
Y1
17.63416MHz
12.67917MHz
Crystal, 4.5pF load capacitance
Y2
10.7MHz ceramic filter
10.7MHz ceramic filter
Murata SFECV10.7 series
Note: Component values vary depending on PCB layout.
______________________________________________________________________________________
17
Low-Cost, 315MHz, 345MHz, and 433.92MHz
ASK Transceiver with Fractional-N PLL
MAX7030
Typical Application Circuit
AGC0
AGC1
AGC2
VDD
Y1
VDD
27
26
25
N.C.
28
DVDD
29
HVIN
PAVDD
30
AGC2
1
31
AGC1
32
AGC0
VDD
XTAL1
C23
C24
C19
C18
C20
C21
XTAL2
3.0V
2
24
DATA
C22
ROUT
23
ENABLE
R3*
C1
4
L1
5
VDD
6
C5
OP+
19
C17
C6
L4
LNAIN
LNASRC
9
11
10
C10
12
C12
C9
13
C13
15
14
PDMAX
8
PDMIN
DS+
7
IFIN+
L6
IFIN-
L3
EXPOSED
PAD
AVDD
MIXOUT
C7
C8
20
DF
PAOUT
MIXIN-
C4
C3
21
N.C.
MAX7030
TX/RX2
MIXIN+
L2
TRANSMIT/
RECEIVE
TX/RX1
LNAOUT
C2
ENABLE
22
T/R
3
DATA
DS-
16
18
17
R1
C15
VDD
L5
IN
C11
C16
GND
Y2
R2
OUT
C14
*OPTIONAL POWER-ADJUST RESISTOR
Chip Information
PROCESS: CMOS
18
Package Information
For the latest package outline information and land patterns, go
to www.maxim-ic.com/packages.
PACKAGE TYPE
PACKAGE CODE
DOCUMENT NO.
32 Thin QFN-EP
T3255-3
21-0140
______________________________________________________________________________________
Low-Cost, 315MHz, 345MHz, and 433.92MHz
ASK Transceiver with Fractional-N PLL
LNAOUT MIXIN+ MIXIN9
10
MIXOUT
IFIN+
IFIN-
12
14
13
11
IF LIMITING
AMPS
0°
LNAIN
7
LNASRC
8
LNA
Σ
90°
I
Q
20 DF
RSSI
100kΩ
19 OP+
RX
FREQUENCY
DIVIDER
XTAL1
DATA FILTER
18 DS+
31
CRYSTAL
OSCILLATOR
XTAL2
100kΩ
RX VCO
PHASE
DETECTOR
32
TX
FREQUENCY
DIVIDER
15 PDMIN
CHARGE
PUMP
16 PDMAX
TX VCO
HVIN 27
3.0V
REGULATOR
∆Σ
MODULATOR
LOOP FILTER
17 DSRX
DATA
AVDD
6
EXPOSED
PAD
MAX7030
30 AGC0
PA
29 AGC1
DIGITAL LOGIC
28 AGC2
24 DATA
2
1
5
3
4
22
26
23
ROUT
PAVDD
PAOUT
TX/RX1
TX/RX2
T/R
DVDD
ENABLE
______________________________________________________________________________________
19
MAX7030
Functional Diagram
MAX7030
Low-Cost, 315MHz, 345MHz, and 433.92MHz
ASK Transceiver with Fractional-N PLL
Revision History
PAGES
CHANGED
REVISION
NUMBER
REVISION
DATE
0
5/05
Initial release
—
1
9/08
Added + to each part to denote lead-free/RoHS-compliant package and explicitly
calling out the odd frequency as contact factory for availability
1
2
6/09
Made correction in Power Amplifier (PA) section
15
DESCRIPTION
Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are
implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.
20 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600
© 2009 Maxim Integrated Products
Maxim is a registered trademark of Maxim Integrated Products, Inc.