Features: Small Size 5.0 mm x 5.0 mm x 0.75 mm 28-Pin LLP
RF Synthesizer System
Integrated RF VCO
Integrated Loop Filter
Low Spurious, Low Phase Noise Fractional-N RF
PLL Based on 11-Bit ∆ modulator
5 kHz Frequency Resolution
Cellular-CDMA LO: 2105.28 MHz to 2155.14 MHz
(Requires an External LO /2 Circuit)
GPS LO: 2087.73 MHz
(Requires an External LO /1.5 Circuit)
IF Synthesizer System Integer-N IF PLL Programmable Charge Pump Current Levels IF LO: 367.20 MHz
Supports Various Reference Oscillator Frequencies: 19.20 MHz/ 19.68 MHz
Low Current Consumption: 22 mA typical at 2.8V
2.7V to 3.3V Operation
RF Digital Filtered Lock Detect Output
Hardware and Software Powerdown ControlApplication Cellular-CDMA 1xRTT and IS-95 Mobile Handsets with GPS
Cellular-CDMA 1xRTT and IS-95 Mobile Data Systems with GPSPinout
Specifications
| VCO Freq Range |
2087-2155 |
| PLL Type |
PLL + VCO |
| Wireless Standard |
CDMA |
| LVCMOS Outputs |
1 |
| Integrated Loop Filter |
Yes |
| RF PLL |
Sigma-Delta |
| IF PLL |
Integer |
| Phase Noise |
-134 dBc/Hz |
| Frequency Offset |
at 900kHz |
| Supply Current |
22 mA |
| Supply Min |
2.7 Volt |
| Supply Max |
3.3 Volt |
| Temperature Min |
-30 deg C |
| Temperature Max |
85 deg C |
| View Using Catalog |
Power Supply Voltage
VCC to GND .............................................−0.3V to +3.6V
VDD to GND ..............................................−0.3V to +3.6V
Voltage on any pin to GND (VIN)
VIN must be < +3.6V .........................−0.3V to VCC+0.3V
...........................................................−0.3V to VDD+0.3V
Storage Temperature Range (TS) ......−65°C to +150°C
Lead Temperature (solder 4 s) (TL) ....................+260°C
DescriptionLMX2542 is a highly integrated, high performance, low power frequency synthesizer system optimized for Cellular-CDMA 1xRTT and IS-95 mobile handsets and data systems with GPS capabilities. Using a proprietary digital phase locked loop technique, LMX2542 provides very stable, low noise local oscillator (LO) signals for up and down conversion in wireless communications devices.
LMX2542 includes a Voltage Controlled Oscillator (VCO) for both the Cellular-CDMA and GPS frequency bands, a loop filter, and a Fractional-N RF PLL based on a Delta Sigma ([Delta][Sigma]) modulator. In concert, these blocks form a closed loop RF synthesizer system. The RF synthesizer system operates from 2087.73 MHz to 2155.14 MHz.
LMX2542 includes an Integer-N IF PLL also. For more flexible loop filter designs, the IF PLL includes a 4-level programmable charge pump. Together with an external VCO and loop filter, LMX2542 makes a complete closed loop IF synthesizer system. The default IF frequency is 367.20 MHz.
Serial data is transferred to the device via a three-wire MICROWIRETM interface (DATA, LE, CLK).
Operating supply voltage ranges from 2.7V to 3.3V. LMX2542 features low current consumption: 22 mA at 2.8V.
LMX2542 is available in a 28-Pin Leadless Leadframe Package (LLP).
Design Tools
| Title |
Size in Kbytes |
Date |
|
|
|
| LMX2542 Evaluation Board Instructions |
619 Kbytes |
30-Apr-2004 |
View Online |
Download |
|
If you have trouble printing or viewing PDF file(s), see Printing Problems.
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LMX2542 is a highly integrated, high performance, low power frequency synthesizer system optimized for Cellular- CDMA 1xRTT and IS-95 mobile handsets and data systems with GPS capabilities. Using a proprietary digital phase locked loop technique, LMX2542 provides very stable, low noise local oscillator (LO) signals for up and down conversion in wireless communications devices. LMX2542 includes a Voltage Controlled Oscillator (VCO) for both the Cellular-CDMA and GPS frequency bands, a loop filter, and a Fractional-N RF PLL based on a Delta Sigma (∆) modulator. In concert, these blocks form a closed loop RF synthesizer system.
The RF synthesizer system operates from 2087.73 MHz to 2155.14 MHz. LMX2542 includes an Integer-N IF PLL also. For more flexible loop filter designs, the IF PLL includes a 4-level programmable charge pump. Together with an external VCO and loop filter, LMX2542 makes a complete closed loop IF synthesizer system. The default IF frequency is 367.20 MHz. Serial data is transferred to the device via a three-wire MICROWIRETM interface (DATA, LE, CLK). Operating supply voltage ranges from 2.7V to 3.3V. LMX2542 features low current consumption: 22 mA at 2.8V. LMX2542 is available in a 28-Pin Leadless Leadframe Package (LLP).
LMX2542 Data Sheet
