MICRF219
300MHz to 450MHz ASK Receiver with
RSSI, Auto-Poll, Bit-Check and Squelch
NOT RECOMMENDED
REFER TO MICRF219A FOR NEW DESIGNS
General Description
The MICRF219 is a 300MHz to 450MHz super-
heterodyne, image-reject, RF receiver with Automatic
Gain Control, OOK/ASK demodulator and analog RSSI
output. The device integrates Auto-Poll, Valid Bit-Check,
Squelch, and Desense features. It only requires a
crystal and a minimum number of external components
to implement. It is ideal for low-cost, low-power, RKE,
TPMS, and remote actuation applications.
Features
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–110dBm sensitivity at 1kbps with 1% BER
Supports data rates up to 10kbps at 433.92MHz
25dB Image-Reject Mixer
No IF Filter Required
60dB Analog RSSI Output
3.0V to 3.6V Supply Voltage Range
4.0mA supply current at 315MHz (continuous receive)
6.0mA supply current at 434MHz (continuous receive)
0.5uA supply current in Shutdown Mode
Optional Auto-Polling (sleep mode, current < 0.1mA)
Optional Valid Bit-Check in Auto-Poll Mode
Optional Programmable 6dB to 42dB Desense
Optional Data Output Squelch until valid bits detected
16-pin QSOP Package (4.9mm x 6.0mm)
−40°C
to +105°C Temperature Range
2kV HBM ESD Rating
Evaluation board QR219BPF Available
The MICRF219 achieves
−110dBm
sensitivity at a data
rate of 1kbps (Manchester encoded). Four demodulator
filter bandwidths are selectable in binary steps from
1625Hz to 13kHz at 433MHz, allowing the device to
support data rates to 10kbps. The device operates from
a supply voltage of 3.0V to 3.6V, and consumes 4.0mA
of supply current at 315MHz and 6.0mA at 433.92MHz.
A shutdown mode reduces supply current to 0.5uA. The
Auto-Polling feature allows the MICRF219 to sleep and
poll for user defined periods, thus further reducing
supply current. The Valid Bit-Check feature, when
enabled in Auto-Poll mode, fully awakes the receiver
and sends bits to the microcontroller once a valid
number of bits are detected. During normal operation an
Ordering Information
optional Squelch feature disables the data output until
Part Number
Temperature Range
Package
valid bits are detected. An optional Desense feature
reduces gain by 6dB to 42dB, distancing the receiver
MICRF219AYQS
16-Pin QSOP
−40°C
to +105°C
from distantly placed, undesired transmitters.
_______________________________________________________________________________________________
Typical Application
QwikRadio is a registered 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
June 2011
M9999-060811
(408) 944-0800
Micrel
MICRF219
Pin Configuration
RO1
GNDRF
ANT
GNDRF
Vdd
SQ
SEL0
SHDN
1
2
3
4
5
6
7
8
16 RO2
15 SCLK
14 RSSI
13 CAGC
12 CTH
11 SEL1
10 DO
9 GND
MICRF219AYQS
Pin Description
16-Pin
QSOP
1
2
3
4
5
6
Pin Name
RO1
GNDRF
ANT
GNDRF
VDD
SQ
Pin Function
Reference Oscillator Input: Reference resonator input connection to pierce oscillator stage. May also
be driven by external reference signal of 200mVp-p to 1.5V p-p amplitude maximum. Internal
capacitance of 7pF to GND during normal operation.
Negative supply connection associated with ANT RF input.
Antenna Input: RF signal input from antenna. Internally AC coupled. It is recommended a matching
network with an inductor-to-RF ground be used to improve ESD protection.
Ground connection for ANT RF input.
Positive supply connection for all chip functions. Bypass with 0.1µF capacitor located as close to the
VDD pin as possible.
Squelch Control Logic-Level Input. An internal pull-up pulls the logic-input HIGH when the device is
enabled. Bit D17 sets whether squelch is enabled or disabled when a logic-level signal is applied the
SQ pin. See Squelch Enable Truth-Table on page
Demodulator Filter Bandwidth Select Logic-Level Input. Internal pull-up (3uA typical) when not in
shutdown or SLEEP mode. Used in conjunction with SEL1 to control D3 bandwidth LSB when serial
interface contains default setting. It does not need to be defined in SLEEP mode.
Shutdown control Logic-Level Input. A logic-level LOW enables the device. A logic-level HIGH places
the device in low-power shutdown mode. An internal pull-up pulls the logic input HIGH.
Negative supply connection for all chip functions except for RF input.
Data Input and Output. Demodulated data output. May be blanked until bit checking test is acceptable.
A current limited CMOS output during normal operation this pin is also used as a CMOS Schmitt input
for serial interface data. A 25kΩ pull-down is present when device is in shutdown and sleep modes.
Demodulator Filter Bandwidth Select Logic-Level Input: Internal (3uA typical) pull-up when not in
shutdown or SLEEP mode. Used in conjunction with SEL0, to control D4 bandwidth MSB, when serial
interface contains default setting. It does not need to be defined in SLEEP mode.
Demodulation threshold voltage integration capacitor. Capacitor-to-GND sets the settling time for the
demodulation data slicing level. Values above 1nF are recommended and should be optimized for data
rate and data profile.
AGC filter capacitor. A capacitor, normally greater than 0.47μF, is connected from this pin-to-GND
Received signal strength indication (output): Output is from a switched capacitor integrating op amp
with 220Ω typical output impedance.
Serial interface input clock. CMOS Schmitt input. A 25kΩ pull-down is present when device is in
shutdown mode.
Reference resonator connection. Internal capacitance of 7pF to GND during normal operation.
7
8
9
10
SEL0
SHDN
GND
DO
11
SEL1
12
13
14
15
16
CTH
CAGC
RSSI
SCLK
RO2
June 2011
2
M9999-060811
(408) 944-0800
Micrel
MICRF219
Absolute Maximum Ratings
(1)
Supply Voltage (VDD) ................................................ +5V
Input Voltage. ............................................................. +5V
Junction Temperature ...........................................+150ºC
Lead Temperature (soldering, 10sec.) ....................300°C
Storage Temperature (Ts)...................... -65ºC to +150°C
Maximum Receiver Input Power ......................... +10dBm
EDS Rating
(3)
................................................... 2KV HBM
Operating Ratings
(2)
Supply voltage (VDD).............................+3.0V to +3.6V
Ambient Temperature (T
A
) ................. –40°C to +105°C
Input Voltage (Vin) ................................................. 3.6V
Maximum Input RF Power................................
−20dBm
Receive Modulation Duty Cycle
(6)
.................... 20~80%
Frequency Range...........................300MHz to 450MHz
Electrical Characteristics
Specifications apply for V
DD
= 3.3V, GND = 0V, C
AGC
= 4.7µF, C
TH
= 0.1µF, f
RX
= 433.92 MHz unless otherwise noted.
Bold
values
indicate –40°C – T
A
– 105°C. 1kbps data rate (Manchester encoded), reference oscillator frequency = 13.52127MHz.
Parameter
Operating Supply Current
Shutdown Current
Receiver
Image Rejection
1
st
IF Center Frequency
Receiver Sensitivity @ 1kbps
(Note 4)
IF Bandwidth
Antenna Input Impedance
Receive Modulation Duty Cycle
AGC Attack / Decay Ratio
AGC Pin Leakage Current
AGC Dynamic Range
Reference Oscillator
Reference Oscillator Frequency
Reference Oscillator Input
Impedance
Reference Oscillator Bias Voltage
f
RX
= 315 MHz, Crystal Load Cap = 10pF
f
RX
= 433.92 MHz, Crystal Load Cap = 10pF
RO1
RO2
9.81563
13.52127
1.6
1.15
MHz
kΩ
V
f
RX
= 315MHz
f
RX
= 433.92MHz
f
RX
= 315 MHz, 50Ω BER=10
-2
f
RX
= 433.92MHz, 50Ω BER=10
-2
f
RX
= 315MHz
f
RX
= 433.92MHz
f
RX
= 315MHz
f
RX
= 433.92MHz
Note 5
t
ATTACK
/ t
DECAY
T
A
= 25ºC
T
A
=
+105ºC
RF
IN
@
−40dBm
RF
IN
@
−100dBm
20
0.1
±30
±800
1.15
1.70
nA
nA
V
V
25
0.86
1.2
−110
−110
235
330
32 – j235
19 – j174
80
dB
MHz
dBm
kHz
Ω
%
Condition
Continuous Operation, f
RX
= 315MHz
Continuous Operation, f
RX
= 433.92MHz
Min.
Typ.
4.0
6.0
0.15
Max.
Units
mA
µA
June 2011
3
M9999-060811
(408) 944-0800
Micrel
MICRF219
Electrical Characteristics (Continued)
Specifications apply for V
DD
= 3.3V, GND = 0V, C
AGC
= 4.7µF, C
TH
= 0.1µF, f
RX
= 433.92 MHz unless otherwise noted. Bold values
indicate –40°C – T
A
– 105°C. 1kbps data rate (Manchester encoded), reference oscillator frequency = 13.52127MHz.
Parameter
Reference Oscillator Input Range
Reference Oscillator Source
Current
Demodulator
CTH Source Impedance
CTH Leakage Current
Demodulator Filter Bandwidth
@ 315MHz
Demodulator Filter Bandwidth
@ 434MHz
Digital / Control Functions
DO Pin Output Current
Output Rise And Fall Times
Input High Voltage
Input Low Voltage
Output Voltage High
Output Voltage Low
RSSI
RSSI DC Output Voltage Range
RSSI Response Slope
RSSI Output Current
RSSI Output Impedance
RSSI Response Time
Notes:
1.
2.
3.
4.
5.
Exceeding the absolute maximum rating may damage the device.
The device is not guaranteed to function outside of its operating rating.
Device is ESD sensitive. Use appropriate ESD precautions. Exceeding the absolute maximum rating may damage the device.
Sensitivity is defined as the average signal level measured at the input necessary to achieve 10
-2
BER (bit error rate). The input signal is defined
as a return-to-zero (RZ) waveform with 50% average duty cycle (Manchester encoded) at a data rate of 1kbps.
When data burst does not contain preamble, duty cycle is defined as total duty cycle, including any “quiet” time between data bursts. When data
bursts contain preamble sufficient to charge the slice level on capacitor C
TH
, then duty cycle is the effective duty cycle of the burst alone. [For
example, 100msec burst with 50% duty cycle, and 100msec “quiet” time between bursts. If burst includes preamble, duty cycle is
T
ON
/(T
ON
+t
OFF
)= 50%; without preamble, duty cycle is T
ON
/(T
ON
+ T
OFF
+ T
QUIET
) = 50msec/(200msec)=25%. T
ON
is the (Average number of
1’s/burst) × bit time, and T
OFF
= (T
BURST
– T
ON
.)
Condition
Min.
0.2
Typ.
Max.
1.5
Units
V
P-P
µA
V(REFOSC) = 0V
300
F
REFOSC
= 9.81563 MHz
F
REFOSC
= 13.52127MHz
T
A
= 25ºC
T
A
= +105ºC
Programmable, see application section
Programmable, see application section
1170
1625
165
120
±2
±800
9400
13000
kΩ
nA
Hz
Hz
As output source @ 0.8 V
DD
sink @ 0.2 V
DD
CI = 15pF, pin DO, 10-90%
Pins SCLK, DO (As input), SHDN,SEL0,
SEL1,SQ
Pins SCLK, DO (As input), SHDN, SEL0,
SEL1,SQ
DO
DO
−100dBm
−40dBm
−110dBm
to -40dBm
0.8V
DD
0.8V
DD
260
600
2
µA
µsec
V
0.2V
DD
V
V
0.2V
DD
V
0.4
2.0
25
400
250
V
mV/dB
µA
Ω
sec
50% data duty cycle, input power to Antenna = -
20dBm
0.3
June 2011
4
M9999-060811
(408) 944-0800
Micrel
MICRF219
Typical Characteristics
-50
-60
SELECTIVITY (dBm)
-70
-80
-90
-100
-110
-120
433MHz Selectivity and
Bandwidth by Different Temps.
-40°C
+105°C
+20°C
433.92MHz V/I by Temperatures
7
105°C
6.5
CURRENT (mA)
6
5.5
5
4.5
4
3.0
3.1
3.2 3.3 3.4
VOLTAGE (V)
3.5
3.6
20°C
-40°C
June 2011
5
432.9
433.1
433.3
433.5
433.7
433.9
434.1
434.3
434.5
434.7
434.9
FREQUENCY (MHz)
M9999-060811
(408) 944-0800