MICRF007YM Micrel Inc, MICRF007YM Datasheet - Page 6

• Manufacturer Part Number: MICRF007YM
• Description: IC RECEIVER UHF LOW POWER 8SOIC
• Manufacturer: Micrel Inc

Specifications of MICRF007YM

• Frequency: 300MHz ~ 440MHz
• Sensitivity: -96dBm
• Data Rate - Maximum: 2.1 kbps
• Modulation Or Protocol: ASK, OOK
• Applications: RKE
• Current - Receiving: 3mA
• Data Interface: PCB, Surface Mount
• Antenna Connector: PCB, Surface Mount
• Features: Automatic Tuning
• Voltage - Supply: 4.75 V ~ 5.5 V
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 8-SOIC (0.154", 3.90mm Width)
• Receiving Current: 5.7mA
• Data Rate: 3.2Kbps
• Modulation Type: ASK, OOK
• Frequency Range: 300MHz To 440MHz
• Sensitivity Dbm: -99dBm
• Rf Ic Case Style: SOIC
• No. Of Pins: 8
• Operating Band Frequency: 300 to 440MHz
• Operating Temperature (min): -40C
• Operating Temperature (max): 85C
• Operating Temperature Classification: Industrial
• Product Depth (mm): 3.94mm
• Product Height (mm): 1.48mm
• Operating Supply Voltage (min): 4.75V
• Operating Supply Voltage (typ): 5V
• Operating Supply Voltage (max): 5.5V
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Memory Size: -
• Lead Free Status / Rohs Status: Compliant
• Other names: 576-1334

MICRF007
Functional Diagram
Applications Information and Functional
Description
Refer to the functional diagram. Three sections of the IC are
identified: UHF Down-converter, OOK Demodulator and Ref-
erence and Control. Also shown are two capacitors (CTH,
CAGC) and one timing component (Y1), usually a crystal.
With the exception of a supply decoupling capacitor, these
are the only external components needed by the MICRF007
to assemble a complete UHF receiver.
For optimal performance, MICRF007 input impedance must
be matched to the antenna impedance. The matching network
will add an additional two or three components.
There is one control input, SHUT pin. The SHUT function is
used to enable the receiver. This input is CMOS compatible,
and is pulled-up on the IC.
Roll-off response of the IF Band-Pass Filter is 5th order, while
the demodulator data filter exhibits a 2nd order response.
The MICRF007 is a standard super-heterodyne receiver with
a narrow IF filter bandwidth of 700kHz. It is less susceptible to
interfering RF signals. The MICRF007 RF center frequency is
controlled by an integrated PLL/VCO frequency synthesizer,
which is locked to the reference oscillator frequency, typically
set by a crystal. A tight tolerance transmitter such as SAW or
crystal-based transmitters must be used for the system.
The MICRF007 has a fully integrated base-band demodulator
filter. The filter has a fixed 2.5kHz bandwidth and exhibits a
2nd order response. This filter limits the receiver raw data
rate to 3.2Kbps NRZ.
M9999-021705
Resonator
Ceramic
Cystal
REFOSC
C
CAGC
AGC
or
SHUT
VDD
ANT
VSS
MICRF007
RF
Amp
f
T
f
RX
Synthesizer
Reference
Oscillator
Control
f
LO
Logic
f
IF
IF
Amp
Reference and Control
Band-Pass Filter
MICRF007 Block Diagram
430kHz
5th Order
UHF Downconverter
IF
Amp
6
Step 1: Selecting Reference Oscillator
All timing and tuning operations on the MICRF007 are de-
rived from the internal Colpitts reference oscillator. Timing
and tuning is controlled through the REFOSC pin in one of
two ways:
The specific reference frequency required is related to the
system transmit frequency.
Crystal Selection
Care should be taken to ensure low ESR crystals are se-
lected. “Application Hint 35” provides additional information
and recommended sources for crystals.
When a crystal is used, the minimum voltage is 300mV
using an externally applied signal, it should be AC-coupled
and limited to the operating range of 0.1V
Selecting Reference Oscillator Frequency f
As with any super-heterodyne receiver, the difference between
the internal local oscillator (LO) frequency f
the incoming transmit frequency f
center frequency. Equation 1 may be used to compute the
Design Steps
The following steps are the basic design steps for using
the MICRF007 receiver:
1. Select the reference oscillator
2. Select the C
3. Select the C
1. Connect a crystal.
2. Drive this pin with an external timing signal.
Detector
Control
Peak
AGC
TH
AGC
Low-Pass Filter
Programmable
2nd Order
capacitor
capacitor
Switched-
Capacitor
Resistor
R
OOK Demodulator
SC
TX
should equal the IF
Compa-
rator
February 17, 2005
PP
LO
to 1.5V
T
and
DO
CTH
PP
Micrel
.
C
PP
TH
. If