• 900 MHz receiver downconverter suitable for 900 MHz cellular and cordless applications
• Application selectable on-chip or external oscillator
• Operates from 3.5V supply to 5.0 V supply
• Cascaded SSB noise figure typically 4.2 dB
• LNA noise figure typically 2.2 dB
• IP3 typically > -4 dBm @ 15 mA
• Programmable low-current mode
• Thermally enhanced PSSOP20 package

Summary:   The Texas Instruments TRF1015 is a single-chip RF downconverter suitable for 900-MHz receiver applications. It combines a low-noise amplifier (LNA), a buffered voltage-controlled oscillator (VCO), and an RF mixer into a 20-pin SSOP package with very few external components required.

Power consumption is kept to a minimum and can be further reduced by placing only the required modules in operate mode and the remaining modules in standby mode.

Three independently selectable modes of operation are provided for both the LNA and the mixer. The modes of operations are: standby, low current and improved compression. The improved compression mode is suitable for applications requiring full duplex capability. The improved compression mode is suitable for maintaining receiver sensitivity in the presence of large interfering signals and provides a low bit-error rate (EBR) in digital modulation systems. The three modes of operation are selected in accordance with the high or low signal present on PD1 and PD2.

The LNA has a gain of 13dB and a noise figure of 2.2 dB. Input and output characteristic impedances of the LNA are 50 Ohms. The single balanced RF mixer has a gain of 9 dB with a single-sidebanded (SSB) noise figure of 10 dB. The VCO has a typical tuning range of 25 MHz using an external varactor and resonator. The VCO gain and tuning range can be adjusted to meet the phase-locked loop (PLL) design requirement with an external shunt and feedback capacitors in series with the resonator. A buffered output of the VCO signal is provided for phase locking capability and can be configured for single-ended of differential operation.