RX5000 RFM, RX5000 Datasheet - Page 8

• Manufacturer Part Number: RX5000
• Description: ASH RX 115.2 KBPS 433.92 MHZ
• Manufacturer: RFM
• Type: Receiverr

Specifications of RX5000

• Frequency: 433.92MHz
• Sensitivity: -109dBm
• Data Rate - Maximum: 115.2kbps
• Modulation Or Protocol: ASK, OOK
• Applications: General Data Transfer
• Current - Receiving: 3.8mA
• Data Interface: PCB, Surface Mount
• Antenna Connector: PCB, Surface Mount
• Voltage - Supply: 2.2 V ~ 3.7 V
• Operating Temperature: -40°C ~ 85°C
• Package / Case: SM-20L
• Operating Frequency: 434.12 MHz
• Operating Supply Voltage: 2.5 V or 3.3 V
• Maximum Operating Temperature: + 85 C
• Minimum Operating Temperature: - 40 C
• Mounting Style: SMD/SMT
• Supply Current: 3 mA
• Lead Free Status / RoHS Status: Lead free by exemption / RoHS compliant by exemption
• Features: -
• Memory Size: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant
• Other names: 583-1074-2

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©2008 by RF Monolithics, Inc.
Pin Descriptions
Pin
1
2
3
4
5
6
7
8
9
AGCCAP
RXDATA
LPFADJ
BBOUT
PKDET
CMPIN
Name
E-mail: [e-mail]
GND1
VCC1
NC
GND1 is the RF ground pin. GND2 and GND3 should be connected to GND1 by short, low-inductance traces.
VCC1 is the positive supply voltage pin for the receiver base-band circuitry. VCC1 must be bypassed by an RF capacitor,
which may be shared with VCC2. See the description of VCC2 (Pin 16) for additional information.
This pin controls the AGC reset operation. A capacitor between this pin and ground sets the minimum time the AGC will hold-
in once it is engaged. The hold-in time is set to avoid AGC chattering. For a given hold-in time t
is:
A ±10% ceramic capacitor should be used at this pin. The value of C
and 2.65* t
through the longest run of zero bits that can occur in a received data stream. The AGC hold-in time can be greater than the
peak detector decay time, as discussed below. However, the AGC hold-in time should not be set too long, or the receiver will
be slow in returning to full sensitivity once the AGC is engaged by noise or interference. The use of AGC is optional when
using OOK modulation with data pulses of at least 30 µs. AGC operation can be defeated by connecting this pin to Vcc.
Active or latched AGC operation is required for ASK modulation and/or for data pulses of less than 30 µs. The AGC can be
latched on once engaged by connecting a 150 K resistor between this pin and ground, instead of a capacitor. AGC operation
depends on a functioning peak detector, as discussed below. The AGC capacitor is discharged in the receiver power-down
(sleep) mode.
This pin controls the peak detector operation. A capacitor between this pin and ground sets the peak detector attack and
decay times, which have a fixed 1:1000 ratio. For most applications, these time constants should be coordinated with the
base-band time constant. For a given base-band capacitor C
A ±10% ceramic capacitor should be used at this pin. This time constant will vary between t
in supply voltage, temperature, etc. The capacitor is driven from a 200 ohm “attack” source, and decays through a 200 K
load. The peak detector is used to drive the “dB-below-peak” data slicer and the AGC release function. The AGC hold-in time
can be extended beyond the peak detector decay time with the AGC capacitor, as discussed above. Where low data rates
and OOK modulation are used, the “dB-below-peak” data slicer and the AGC are optional. In this case, the PKDET pin and
the THLD2 pin can be left unconnected, and the AGC pin can be connected to Vcc to reduce the number of external compo-
nents needed. The peak detector capacitor is discharged in the receiver power-down (sleep) mode.
BBOUT is the receiver base-band output pin. This pin drives the CMPIN pin through a coupling capacitor C
data slicer operation. The time constant t
A ±10% ceramic capacitor should be used between BBOUT and CMPIN. The time constant can vary between t
1.8*t
on the data rate, data run length, and other factors as discussed in the ASH Transceiver Designer’s Guide. A common criteria
is to set the time constant for no more than a 20% voltage droop during SP
The output from this pin can also be used to drive an external data recovery process (DSP, etc.). The nominal output imped-
ance of this pin is 1 K. When the receiver RF amplifiers are operating at a 50%-50% duty cycle, the BBOUT signal changes
about 10 mV/dB, with a peak-to-peak signal level of up to 685 mV. For lower duty cycles, the mV/dB slope and peak-to-peak
signal level are proportionately less. The signal at BBOUT is riding on a 1.1 Vdc value that varies somewhat with supply volt-
age and temperature, so it should be coupled through a capacitor to an external load. A load impedance of 50 K to 500 K in
parallel with no more than 10 pF is recommended. When an external data recovery process is used with AGC, BBOUT must
be coupled to the external data recovery process and CMPIN by separate series coupling capacitors. The AGC reset function
is driven by the signal applied to CMPIN. When the receiver is in power-down (sleep) mode, the output impedance of this pin
becomes very high, preserving the charge on the coupling capacitor.
This pin is the input to the internal data slicers. It is driven from BBOUT through a coupling capacitor. The input impedance of
this pin is 70 K to 100 K.
RXDATA is the receiver data output pin. This pin will drive a 10 pF, 500 K parallel load. The peak current available from this
pin increases with the receiver low-pass filter cutoff frequency. In the power-down (sleep) mode, this pin becomes high
impedance. If required, a 1000 K pull-up or pull-down resistor can be used to establish a definite logic state when this pin is
high impedance. If a pull-up resistor is used, the positive supply end should be connected to a voltage no greater than Vcc +
200 mV.
This pin may be left unconnected or may be grounded.
This pin is the receiver low-pass filter bandwidth adjust. The filter bandwidth is set by a resistor R
ground. The resistor value can range from 330 K to 820 ohms, providing a filter 3 dB bandwidth f
The resistor value is determined by:
A ±5% resistor should be used to set the filter bandwidth. This will provide a 3 dB filter bandwidth between f
with variations in supply voltage, temperature, etc. The filter provides a three-pole, 0.05 degree equiripple phase response.
The peak drive current available from RXDATA increases in proportion to the filter bandwidth setting.
BBC
C
C
t
C
R
BBC
AGC
PKD
with variations in supply voltage, temperature, etc. The optimum time constant in a given circumstance will depend
BBO
LPF
AGH
= 0.064*C
= 1445/ f
= 0.33* C
= 70*SP
= 19.1* t
, depending on operating voltage, temperature, etc. The hold-in time is chosen to allow the AGC to ride
MAX
LPF
AGH
BBO
BBO
, where R
, where SP
, where t
, where t
, where C
AGH
LPF
BBC
MAX
BBO
is in µs and C
is in kilohms, and f
is in µs and C
BBC
and C
is the maximum signal pulse width in µs and C
for this connection is:
PKD
are in pF
AGC
BBO
Description
is in pF
LPF
is in pF
BBO
is in kHz
, the capacitor value C
AGC
given above provides a hold-in time between t
MAX
. For this case:
PKD
BBO
PKA
is:
is in pF
AGH
LPF
and 1.5* t
LPF
, the capacitor value C
from 4.5 kHz to 1.8 MHz.
between this pin and
PKA
LPF
BBO
with variations
and 1.3* f
BBC
RX5000 - 4/7/08
for internal
Page 8 of 10
and
AGH
AGC
LPF