The LMX3161 Single Chip Radio Transceiverisamonolithic,
integrated radio transceiver optimized for use in a Digital Enhanced Cordless Telecommunications (DECT) system. It is
fabricated using National’s ABiC V BiCMOS process
=
(f
18 GHz).
T
The LMX3161 contains phase locked loop (PLL), transmit
and receive functions. The 1.1 GHz PLL block is shared between transmit and receive section. The transmitter includes
a frequency doubler, and a high frequency buffer. The receiver consists of a 2.0 GHz lownoisemixer,anintermediate
frequency (IF) amplifier, a high gain limiting amplifier, a frequency discriminator, a received signal strength indicator
(RSSI), and an analog DC compensation loop. The PLL,
doubler, and buffers can be used to implement open loop
modulation along with an external VCO and loop filter. The
circuit features on-chip voltage regulation to allow supply
voltages ranging from 3.0V to 5.5V. Two additional voltage
regulators provide a stable supply source to external discrete stages in the Tx and Rx chains.
The IF amplifier, high gain limiting amplifier, and discriminator are optimized for 110 MHz operation, with a total IF gain
of 85 dB. The single conversion receiver architecture pro-
LMX3161 Single Chip Radio Transceiver
PRELIMINARY
November 1999
vides a low cost, high performance solution for communications systems. The RSSI output may be used for channel
quality monitoring.
The Single Chip Radio Transceiver is available in a 48-pin
7mm X 7mm X 1.4mm PQFP surface mount plastic package.
Features
n Single chip solution for DECT RF transceiver
n RF sensitivity to −93 dBm; RSSI sensitivity to −100 dBm
n Two regulated voltage outputs for discrete amplifiers
n High gain (85 dB) intermediate frequency strip
n Allows unregulated 3.0V–5.5V supply voltage
n Power down mode for increased current savings
n System noise figure 6.5 dB (typ)
Applications
n Digital Enhanced Cordless Telecommunications (DECT)
n Personal wireless communications (PCS/PCN)
n Wireless local area networks (WLANs)
n Other wireless communications systems
Block Diagram
DS012815-1
MICROWIRE™is a trademark of National Semiconductor Corporation.
®
TRI-STATE
is a registered trademark of National Semiconductor Corporation.
16CEIChip Enable. Pulling LOW powers down entire chip. Taking CE HIGH powers up the
17V
18D
19V
P
o
CC
20GND—Ground.
21OUT 0OProgrammable CMOS output. Refer to Function Register Programming Description section
22Rx PD/OUT 1I/OReceiver power down control input or programmable CMOS output. Refer to Function
23Tx PD/OUT 2I/OTransmitter power down control input or programmable CMOS output. Refer to Function
24PLL PDIPLL power down control input. LOW for PLL normal operations, and HIGH for PLL power
25CLOCKIMICROWIRE
26DATAIMICROWIRE data input. High impedance CMOS input with Schmitt Trigger.
27LEIMICROWIRE load enable input. High impedance CMOS input with Schmitt Trigger.
28OSC
IN
29S FIELD
30RSSI
OUT
31THRESHOThreshold level to external comparator.
32DC COMP
33DISC
OUT
34GND—Ground.
35V
CC
36QUAD
37V
CC
38GND—Ground.
39V
CC
40GND—Ground.
41V
CC
—Power supply for CMOS section of PLL and ESD bussing.
OIF output from the mixer.
—Power supply for mixer section.
IRF input to the mixer.
—Regulated power supply for external PA gain stage.
—Power supply for analog sections of PLL and doubler.
OFrequency doubler output.
—Power supply for analog sections of PLL and doubler.
IRF Input to PLL and frequency doubler.
appropriate functional blocks depending on the state of bits F6, F7, F11, and F12
programmed in F-latch. It is necessary to initialize the internal registers once, after the
power up reset. The registers’ contents are kept even in power-down condition.
—Power supply for charge pump.
OCharge pump output. For connection to a loop filter for driving the input of an external VCO.
—Power supply for CMOS section of PLL and ESD bussing.
for details.
Register Programming Description section for details.
Register Programming Description section for details.
saving.
™
clock input. High impedance CMOS input with Schmitt Trigger.
IOscillator input. High impedance CMOS input with feedback.
IDC compensation circuit enable. While LOW, the DC compensation circuit is enabled and
the threshold is updated through the DC compensation loop. While HIGH, the switch is
opened, and the comparator threshold is held by the external capacitor.
OReceived signal strength indicator (RSSI) output.
IInput to DC compensation circuit.
IN
ODemodulated output of discriminator.
—Power supply for the discriminator circuit.
IN
IQuadrature input for tank circuit.
—Power supply for limiter output stage.
—Power supply for limiter gain stages.
—Power supply for IF amplifier gain stages.
LMX3161
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LMX3161 Pin Diagram (Continued)
Pin No.Pin NameI/ODescription
LMX3161
42LIM
IN
43GND—Ground.
44IF
45V
OUT
CC
46GND—Ground.
47IF
48Rx V
IN
REG
IIF input to the limiter.
OIF output from IF amplifier.
—Power supply for IF amplifier output.
IIF input to IF amplifier.
—Regulated power supply for external LNA stages.
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Absolute Maximum Ratings (Notes 1, 2)
Power Supply Voltage (V
V
P
Voltage on Any Pin with
GND=0V (V
)−0.3V to VCC+0.3V
I
Storage Temperature Range (T
Lead Temp. (solder, 4 sec)(T
)−0.3V to +6.5V
CC
−0.3V to +6.5V
)−65˚C to +150˚C
S
)+260˚C
L
Recommended Operating
Conditions
Supply Voltage (VCC)3.0V to 5.5V
Operating Temperature (T
Note 1: Absolute Maximum Ratings indicate limits beyond which damage to
the device may occur. Recommended Operating Conditions indicate conditions for which the device is intended to be functional, but do not guarantee
specific performance limits. For guaranteed specifications and test conditions, see the Electrical Characteristics section. The guaranteed specifications apply only for the test conditions listed.
Note 2: This device is a high performance RFintegrated circuit with an ESD
<
KeV and is ESD sensitive. Handling and assembly of this device