MICRF620
434MHz ISM Band Transceiver Module
RadioWire is a trademark of Micrel, Inc.
Micrel Inc. 2180 Fortune Drive San Jose, CA 95131 USA tel +1 (
408
) 944-0800 fax + 1 (408) 474-1000 http://www.micrel.com
December 2005
M9999-120205
General Description
The MICRF620 is a self-contained frequency shift keying
(FSK) transceiver module, intended for use in half-duplex,
bidirectional RF links. The multi-channeled FSK
transceiver module is intended for UHF radio equipment in
compliance with the European Telecommunication
Standard Institute (ETSI) specification, EN300 220.
The transmitter consists of a fully programmable PLL
frequency synthesizer and power amplifier. The frequency
synthesizer consists of a voltage-controlled oscillator
(VCO), a crystal oscillator, dual modulus prescaler,
programmable frequency dividers, and a phase-detector.
The output power of the power amplifier can be
programmed to seven levels. A lock-detect circuit detects
when the PLL is in lock.
In receive mode, the PLL synthesizer generates the local
oscillator (LO) signal. The N, M, and A values that give the
LO frequency are stored in the N0, M0, and A0 registers.
The receiver is a zero intermediate frequency (IF) type that
makes channel filtering possible with low-power, integrated
low-pass filters. The receiver consists of a low noise
amplifier (LNA) that drives a quadrature mix pair. The
mixer outputs feed two identical signal channels in phase
quadrature. Each channel includes a pre-amplifier, a third
order Sallen-Key RC low-pass filter that protects the
following switched-capacitor filter from strong adjacent
channel signals, and a limiter. The main channel filter is a
switched-capacitor implementation of a six-pole elliptic low
pass filter. The cut-off frequency of the Sallen-Key RC filter
can be programmed to four different frequencies: 100kHz,
150kHz, 230kHz, and 350kHz. The I and Q channel
outputs are demodulated and produce a digital data
output. The demodulator detects the relative phase of the I
and the Q channel signal. If the I channel signal lags
behind the Q channel, the FSK tone frequency is above
the LO frequency (data "1"). If the I channel leads the Q
channel, then the FSK tone is below the LO frequency
(data "0"). The output of the receiver is available on the
DataIXO pin. A receive signal strength indicator (RSSI)
circuit indicates the received signal level. All support
documentation can be found on Micrel's web site at:
www.micrel.com.
RadioWire
Module
Features
"Drop in" RF solution
Small size: 11.5x14.1mm
RF tested
Low Power
Surface Mountable
Tape & Reel
Digital Bit Synchronizer
Received Signal Strength Indicator (RSSI)
RX and TX power management
Power down function
Register read back function
Applications
Telemetry
Remote metering
Wireless controller
Remote data repeater
Remote control systems
Wireless modem
Wireless security system
Micrel, Inc.
MICRF620
December 2005
2
M9999-120205
Contents
General Description ................................................................................................................................................................ 1
Features .................................................................................................................................................................................. 1
Applications ............................................................................................................................................................................. 1
Contents .................................................................................................................................................................................. 2
RadioWire
RF Module Selection Guide................................................................................................................................. 3
Ordering Information ............................................................................................................................................................... 3
Block Diagram......................................................................................................................................................................... 3
Pin Configuration..................................................................................................................................................................... 4
Pin Description ........................................................................................................................................................................ 4
Absolute Maximum Ratings
(1)
................................................................................................................................................. 5
Operating Ratings
(2)
................................................................................................................................................................ 5
Electrical Characteristics......................................................................................................................................................... 5
Programming........................................................................................................................................................................... 7
General ............................................................................................................................................................................... 7
Writing to the Control Registers in MICRF620 ................................................................................................................... 8
Writing to a Single Register ................................................................................................................................................ 8
Writing to All Registers ....................................................................................................................................................... 8
Writing to n Registers Having Incremental Addresses ....................................................................................................... 9
Reading from the Control Registers in MICRF620 ............................................................................................................. 9
Reading n Registers from MICRF620................................................................................................................................. 9
Programming Interface Timing.............................................................................................................................................. 10
Programming Summary.................................................................................................................................................... 11
Frequency Synthesizer ......................................................................................................................................................... 11
Crystal Oscillator (XCO) ................................................................................................................................................... 11
VCO .................................................................................................................................................................................. 12
Lock Detect ....................................................................................................................................................................... 12
Modes of Operation............................................................................................................................................................... 12
Transceiver Sync/Non-Synchronous Mode ...................................................................................................................... 13
Data Interface ................................................................................................................................................................... 13
Receiver ................................................................................................................................................................................ 13
Front End .......................................................................................................................................................................... 14
Sallen-Key Filters.............................................................................................................................................................. 14
Switched Capacitor Filter.................................................................................................................................................. 14
RSSI.................................................................................................................................................................................. 14
FEE ................................................................................................................................................................................... 15
Bit Synchronizer................................................................................................................................................................ 15
Transmitter ............................................................................................................................................................................ 16
Power Amplifier................................................................................................................................................................. 16
Frequency Modulation ...................................................................................................................................................... 16
Using the XCO-tune Bits ....................................................................................................................................................... 16
Application Circuit Illustration ................................................................................................................................................ 17
Assembling the MICRF620 ................................................................................................................................................... 17
Recommended Reflow Temperature Profile .................................................................................................................... 17
Shock/Vibration during Reflow.......................................................................................................................................... 17
Handassembling the MICRF620....................................................................................................................................... 17
Layout.................................................................................................................................................................................... 18
Recommended Land Pattern............................................................................................................................................ 18
Layout Considerations ...................................................................................................................................................... 18
Package Dimensions ............................................................................................................................................................ 19
Tape Dimensions .................................................................................................................................................................. 19
Micrel, Inc.
MICRF620
December 2005
5
M9999-120205
Absolute Maximum Ratings
(1)
Supply Voltage (V
DD
)...................................................+2.8V
Voltage on any pin (GND = 0V). ..................... -0.3V to 2.8V
Lead Temperature (soldering, 5 sec.)......................+225C
Storage Temperature (T
s
) ............................-30C to +85C
ESD Rating
(3)
..................................................................2kV
Operating Ratings
(2)
Supply voltage (V
IN
) ..................................+2.0V to +2.5V
RF Frequencies.................................410MHz to 450MHz
Data Rate (NRZ) ................................................ <20 kbps
Ambient Temperature (T
A
) .......................20C to +75C
Electrical Characteristics
f
RF
= 434MHz, Data rate = 20kbps, V
DD
= 2.5V; T
A
= 25C,
bold
values indicate 20C< T
A
< +75C, unless noted.
Parameter Condition
Min
Typ
Max
Units
Power Supply
2.0
2.5
V
Power Down Current
0.3
A
Standby Current
280
A
VCO and PLL Section
Tunable with on-chip cap bank
16
MHz
Crystal Oscillator Frequency
Tuning range
-30
+40
ppm
Crystal Initial Tolerance
-10 +10
ppm
Crystal Temperature Tolerance
-10 +10
ppm
Rx 433.4MHz Rx 434MHz
300
s
Rx Tx, same frequency, measured @
frequency offset < 10kHz
200
s
Tx Rx, same frequency, time to good
data
350
s
Standby Rx,
1.1
ms
Switch Time
Standby Tx
1.1
ms
Crystal Oscillator Start-Up Time
XCO_tune=13
750
s
Transmit Section
R
LOAD
= 50
, Pa2_0: 111
10 dBm
Output Power
R
LOAD
= 50
, Pa2_0: 001
-8
dBm
Over temperature range
3
dB
Output Power Tolerance
Over power supply range
3
dB
R
LOAD
= 50
, PA2_0: 111
23 mA
Tx Current Consumption
R
LOAD
= 50
, PA2_0: 001
10 mA
Tx Current Consumption Variation
R
LOAD
= 50
, PA2_0: 111
2.5 mA
Binary FSK Frequency Separation
(5)
Limited by receiver BW
20 400
kHz
Data Rate
NRZ
0 20
kbps
Occupied bandwidth
19.2kbps,
= 9 (85kHz), -36dBm
(RBW=10kHz)
kHz
Harmonics 434
-36
dBm
Spurious Emission in Restricted
bands < 1GHz
-54
dBm
Spurious Emission < 1GHz
-36
dBm
Spurious Emission > 1GHz
ETSI EN300 220
-30
dBm
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