MICREL MICRF103BM

MICRF103
Micrel
MICRF103
QwikRadio™ UHF ASK Transmitter
Final
General Description
Features
The MICRF103 is a single chip Transmitter IC for remote
wireless applications. The device employs Micrel’s latest
QwikRadio™ technology. This device is a true ”data-in,
antenna-out” monolithic device. All antenna tuning is accomplished automatically within the IC which eliminates manual
tuning, and reduces production costs. The result is a highly
reliable yet extremely low cost solution for high volume
wireless applications. Because the MICRF103 is a true
single-chip radio transmitter, it is easy to apply, minimizing
design and production costs, and improving time to market.
The MICRF103 uses a novel architecture where the external
antenna is tuned by the internal UHF synthesizer. This
transmitter is designed to comply worldwide UHF unlicensed
band international radio regulations. The IC is compatible
with virtually all ASK/OOK (Amplitude Shift Keying/On-Off
Keyed) UHF receiver types from wide-band super-regenerative radios to narrow-band, high performance super-heterodyne receivers. The transmitter is designed to work with
transmitter data rates up to 115k bits per second.
The automatic tuning in conjunction with an external resistor,
insures that the transmitter output power stays constant at
maximum regulatory transmit power limits for the life of the
battery.
When coupled with Micrel’s family of QwikRadio™ receivers,
the MICRF103 provides the lowest cost and most reliable
remote actuator and RF link system available.
•
•
•
•
•
•
Complete UHF transmitter on a monolithic chip
Frequency range 800MHz to 1GHz
Data rates to 115kbps
Automatic antenna alignment, no manual adjustment
Low external part count
Low standby current <1µA
Applications
•
•
•
•
Remote keyless entry systems (RKE)
Remote fan/light control
Garage door opener transmitters
Remote sensor data links
Ordering Information
Part Number
Temperature Range
Package
MICRF103BM
–40°C to +85°C
8-Pin SOIC
Typical Application
+5V
ASK DATA INPUT
4.7µF
MICRF103
RP1
100k
0.1µF
PC
RP2
6.8k
1.0pF
8.2pF
27nH
ASK
VDD
ANTP
VSS
ANTM
REFOSC
STBY
10nH
100pF
SAW Filter
1.0pF
50Ω
Monopole
PCB Antenna
Y1
27nH
100k
+5V
Note: Example for 868MHz
Figure 1
QwikRadio is a trademark of Micrel, Inc. The QwikRadio ICs were developed under a partnership agreement with AIT of Orlando, Florida.
Micrel, Inc. • 1849 Fortune Drive • San Jose, CA 95131 • USA • tel + 1 (408) 944-0800 • fax + 1 (408) 944-0970 • http://www.micrel.com
June 2002
1
MICRF103
MICRF103
Micrel
Pin Configuration
PC 1
8 ASK
VDD 2
7 ANTP
VSS 3
6 ANTM
REFOSC 4
5 STBY
MICRF103BM
Pin Description
Pin Number
Pin Name
1
PC
2
VDD
Positive power supply input for the IC.
3
VSS
This pin is the ground return for the IC. A power supply bypass capacitor
connected from VDD to VSS should have the shortest possible path.
4
REFOSC
This is the timing reference frequency which is the transmit frequency
divided by 64. Connect a crystal (mode dependent) between this pin and
VSS, or drive the input with an AC coupled 0.5Vpp input clock. See Reference Oscillator section in this data sheet under Electrical Characteristics.
5
STBY
Input for transmitter stand-by control pin is pulled to VDD for transmit
operation and VSS for stand-by mode.
6
ANTM
Negative RF power output to drive one side of the transmit antenna.
7
ANTP
Positive RF power output to drive the other side of the transmit antenna.
8
ASK
MICRF103
Pin Function
Power Control Input. The voltage at this pin should be set between 0.1V to
0.4V for normal operation.
Amplitude Shift Key modulation data input pin. For CW operation, connect
this pin to VDD.
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June 2002
MICRF103
Micrel
Absolute Maximum Ratings (Note 1)
Operating Ratings (Note 2)
Supply Voltage(VDD) ..................................................... +6V
Voltage on I/O Pins ............................. VSS–0.3 to VDD+0.3
Storage Temperature Range ................... -65°C to + 150°C
Lead Temperature (soldering, 10 seconds) ........... + 300°C
ESD Rating, Note 3
Supply Voltage (VDD) .................................... 4.75V to 5.5V
Maximum Supply Ripple Voltage ............................... 10mV
PC Input Range ...................................... 0.1V < VPC < 0.4V
Ambient Operating Temperature (TA) ........ –40°C to +85°C
Programmable Transmitter Frequency Range:
........................................................ 800MHz to 1GHz
Electrical Characteristics
Specifications apply for 4.75V < VDD < 5.5V, VPC = 0.35V, TA = 25°C, freqREFOSC = 13.5625MHz, STBY = VDD. Bold values indicate
–40°C ≤ TA ≤ 85°C unless otherwise noted.
Parameter
Condition
Min
Typ
Max
Units
Power Supply
µA
Standby Supply Current, IQ
VSTBY < 0.5V
MARK Supply Current, ION
@868MHz
19
26.5
mA
@915MHz
20
27.5
mA
@868MHz
14
18
mA
@915MHz
15
21
mA
33%@868MHz
16
mA
33%@915MHz
17
mA
@868MHz (EIRP)
-3
dBm
@915MHz (EIRP)
-3
dBm
over supply and temperature
±2
dBm
38
45
dBc
2.6
3.0
SPACE Supply Current, IOFF
MARK/SPACE Ratio
0.10
RF Output Section and Modulation Limits:
Maximum Power Level, POUT
Output Power Variation
Extinction ratio for ASK
Varactor tuning range
Note 5
3.3
pF
Reference Oscillator Section
Reference Oscillator Input
Impedance
300
kΩ
Reference Oscillator Source
Current
5.0
µA
Reference Oscillator Input
Voltage (peak-to-peak)
0.2
1.0
VPP
Digital / Control Section
Calibration Time
note 7, ASK=HIGH
20
ms
Power Amplifier Output Hold-off
Time from STBY
note 4, STDBY transition from LOW to HIGH
crystal, ESR < 20Ω
5
ms
Transmitter Stabilization Time
from external reference (500mVpp)
9
ms
From STBY
crystal, ESR < 20Ω
12
ms
Maximum Data rate
- ASK modulation
duty cycle of the modulating signal = 50%
STBY HIGH
VIH
enable voltage
STBY LOW
VIL
ASK Pin
115
kbits/s
0.8VDD
V
0.1VDD
VIH, input high voltage
0.8VDD
V
VIL, input low voltage
ASK Input Current
June 2002
ASK = 0V, 5.0V input current
–10
3
0.1
0.1VDD
V
10
µA
MICRF103
MICRF103
Micrel
Note 1.
Exceeding the absolute maximum rating may damage the device.
Note 2.
The device is not guaranteed to function outside its operating rating.
Note 3.
Devices are ESD sensitive. Handling precautions recommended. Human body model, 1.5k in series with 100pF.
Note 4.
After the release of the STDBY, the device requires an initialization time to settle the REFOSC and the internal PLL. The first MARK state
(ASK HIGH) after exit from STDBY needs to be longer than the initialization time. The subsequent low to high transitions will be treated as
data modulation whereby the envelope transition time will apply.
Note 5.
The varactor capacitance tuning range indicates the allowable external antenna component variation to maintain tune over normal production
tolerances of external components. Guaranteed by design not tested in production.
Note 6.
For the ASK modulation scheme, the part will accept ASK (digital ON/OFF) input and will transmit the data with a finite extinction ratio and the
pin will set the MARK power level.
Note 7.
When the device is first powered up or it loses power momentarily, it goes into the calibration mode to tune up the transmit antenna.
Test Circuit
680pF
MICRF103
PC
STBY
VDD
ANTP
VSS
ANTM
100Ω
200Ω
7.1nH
REFOSC
MICRF103
ASK
4:1
50Ω
680pF
100Ω
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June 2002
MICRF103
Micrel
Typical Characteristics
Mark Current
vs. PC Voltage
Output Power
vs. PC Pin Voltage
35
30
20
MARK POUT (dBm)
MARK ION (mA)
30
25
20
15
10
5
0
0
June 2002
10
0
-10
-20
-30
-40
0.1 0.2 0.3 0.4 0.5 0.6 0.7
VPC (V)
-50
0
0.1 0.2 0.3 0.4 0.5 0.6 0.7
VPC (V)
5
MICRF103
MICRF103
Micrel
Functional Diagram
Reference
Bias
STBY
VDD
ASK
(10)
TX
Bias
Control
VDD
ANTP
Power
Amp
ANTM
(8)
(9)
PC
Prescaler
÷64
Buffer
(6a)
(5)
Phase
Detector
Buffer
VCO (4)
(2)
(6b)
(3)
Antenna
Tuning
Control
(7)
Varactor
Device
REF.OSC
Reference
Oscillator (1)
(11)
VSS
Figure 2. MICRF103 Block Diagram
Functional Description
The block diagram illustrates the basic structure of the
MICRF103. Identified in the figure are the principal functional
blocks of the IC, namely the (1, 2, 3, 4, 5) UHF synthesizer,
(6a/b) Buffer, (7) Antenna tuner, (8) Power amplifier, (9) TX
bias control, (10) Reference bias and (11) Process tuner.
The UHF synthesizer generates the carrier frequency with
quadrature outputs. The in-phase signal (I) is used to drive
the PA and the quadrature signal (Q) is used to compare the
antenna signal phase for antenna tuning purpose.
The antenna tuner block senses the phase of the transmit
signal at the antenna port and controls the varactor capacitor
to tune the antenna.
The power control unit senses the antenna signal and controls the PA bias current to regulate the antenna signal to the
transmit power.
MICRF103
The process tune circuit generates process independent bias
currents for different blocks.
Included within the IC is a differential varactor that serves as
the tuning element to insure that the transmit frequency and
antenna are aligned with the receiver over all supply and
temperature variations.
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June 2002
MICRF103
Micrel
Package Information
0.026 (0.65)
MAX)
PIN 1
DIMENSIONS:
INCHES (MM)
0.154 (3.90)
0.193 (4.90)
0.050 (1.27) 0.016 (0.40)
TYP
TYP
45°
3°–6°
0.063 (1.60) MAX
0.057 (1.45)
0.049 (1.25)
0.197 (5.0)
0.189 (4.8)
0.244 (6.20)
0.228 (5.80)
SEATING
PLANE
8-Pin SOP (M)
MICREL, INC. 1849 FORTUNE DRIVE
TEL
+ 1 (408) 944-0800
FAX
SAN JOSE, CA 95131
+ 1 (408) 944-0970
WEB
USA
http://www.micrel.com
This information is believed to be accurate and reliable, however no responsibility is assumed by Micrel for its use nor for any infringement of patents or
other rights of third parties resulting from its use. No license is granted by implication or otherwise under any patent or patent right of Micrel, Inc.
© 2002 Micrel, Incorporated
June 2002
7
MICRF103