LT5500

LT5500 1.8GHz to 2.7GHz Receiver Front End FEATURES ■ ■ ■ ■ ■ ■ ■ ■ DESCRIPTIO 1.8V to 5.25V Supply Dual LNA Gain Setting: +13.5dB/–14dB at 2.5GHz Double-Balanced Mixer Internal LO Buffer LNA Input Internally Matched Low Supply Current: 23mA Low Shutdown Current: 2µA 24-Lead Narrow SSOP Package The LT®5500 is a receiver front end IC designed for low voltage operation. The chip contains a low noise amplifier (LNA), a Mixer and an LO buffer. The IC is designed to operate over a power supply voltage range from 1.8V to 5.25V. The LNA can be set to either high gain or low gain mode. At 2.5GHz, the high gain mode provides 13.5dB gain and a noise figure (NF) of 4dB. The LNA in low gain mode provides –14dB gain and an IIP3 of + 8dBm at 2.5GHz. The mixer has 5dB of conversion gain and an IIP3 of – 2.5dBm at 2.5GHz, with –10dBm LO input power. , LTC and LT are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. APPLICATIO S ■ ■ ■ IEEE 802.11 and 802.11b DSSS and FHSS High Speed Wireless LAN Wireless Local Loop TYPICAL APPLICATIO ENABLE 100pF GAIN SELECT 100pF 2V 100pF ×2 L4 LNA_IN GND LNA_GND LO – LNA_OUT C4 L2 RF INPUT FILTER RF INPUT EN LT5500 GS 14.0 fRF = 2.5GHz 13.9 TA = 25°C 13.8 13.7 LNA GAIN (dB) 2V VCC 1µF 1nF 100pF ×4 MIX_GND L5 T2 8:1 IF + LO RF IF IF – LO + C17 L3 LO INPUT 13.6 13.5 13.4 13.3 INTERSTAGE FILTER MIX_IN L9 C23 13.2 13.1 13.0 1.5 2 2.5 3 3.5 VCC (V) 4 4.5 5 5.5 IF OUTPUT L7 • • 2V 100pF 5500 F01 Figure 1. 2.5GHz Receiver. Interstage Filter is Optional 5500f U LNA Gain (High Gain Mode) and Mixer Conversion Gain 6.0 5.8 MIXER CONVERSION GAIN (dB) U U 5.6 5.4 5.2 5.0 4.8 4.6 4.4 4.2 4.0 5500 TA02 1 LT5500 ABSOLUTE MAXIMUM RATINGS (Note 1) PACKAGE/ORDER I FOR ATIO TOP VIEW EN VCC LNA_IN GND LNA_GND LNA_GND LNA_GND LNA_GND VCC 1 2 3 4 5 6 7 8 9 24 GS 23 GND 22 LNA_OUT 21 VCC 20 GND 19 LO – 18 LO + 17 VCC 16 GND 15 MIX_IN 14 GND 13 IF – Power Supply Voltage ........................................... 5.5V LNA RF Input Power ............................................ 5dBm Mixer RF Input Power ........................................ 10dBm LO Input Power (Note 2) ................................... 10dBm All Other Pins ......................................................... 5.5V Operating Ambient Temperature Range ............................... – 40°C to 85°C Storage Temperature Range ................ – 65°C to 150°C Lead Temperature (Soldering, 10 sec)................. 300°C ORDER PART NUMBER LT5500EGN MIX_GND 10 GND 11 IF + 12 GN PACKAGE 24-LEAD PLASTIC SSOP TJMAX = 150°C, θJA = 85°C/W Consult LTC Marketing for parts specified with wider operating temperature ranges. ELECTRICAL CHARACTERISTICS SYMBOL PARAMETER Frequency Range (Note 3) Forward Gain Reverse Gain (Isolation) Noise Figure Input Return Loss Output Return Loss Input 1dB Compression Input 3rd Order Intercept LNA Low Gain: EN = 1.35V, GS = 0.3V Frequency Range (Note 4) Forward Gain Reverse Gain (Isolation) Noise Figure Input 1dB Compression Input 3rd Order Intercept Mixer: EN = 1.35V, GS = 1.35V RF Frequency Range (Note 4) Conversion Gain SSB Noise Figure Input P1dB Input 3rd Order Intercept LNA High Gain: EN = 1.35V, GS = 1.35V (Test circuit shown in Figure 3 for 1.8GHz application) VCC = 3V DC, LNA: fLNA_IN = 1.8GHz, Mixer: fMIX_IN = 1.8GHz, fLO = 1.52GHz, PLO = – 10dBm, TA = 25°C, unless otherwise noted. (Notes 3, 4) CONDITIONS MIN TYP 1.8 to 2.7 15.5 Terminated 50Ω Source No External Matching With External Matching Two Tone Test, ∆f = 2MHz –18 18.5 –39 2.5 10.5 15 –24 –12 1.8 to 2.7 –13 –10 –34 16.5 0 Two Tone Test, ∆f = 2MHz 4.5 9 1.8 to 2.7 5.5 Terminated 50Ω Source Two Tone Test, ∆f = 2MHz –6 8.5 7.5 –13 – 2.5 MAX UNITS GHz dB dB dB dB dB dBm dBm GHz dB dB dB dBm dBm GHz dB dB dBm dBm 5500f 2 U W U U WW W LT5500 ELECTRICAL CHARACTERISTICS SYMBOL PARAMETER LO Frequency Range (Note 4) IF Frequency Range (Note 3) LO-IF Isolation LO-RF Isolation RF-LO Isolation (Test circuit shown in Figure 3 for 1.8GHz application) VCC = 3V DC, LNA: fLNA_IN = 1.8GHz, Mixer: fMIX_IN = 1.8GHz, fLO = 1.52GHz, PLO = – 10dBm, TA = 25°C, unless otherwise noted. (Notes 3, 4) CONDITIONS Matching Required Matching Required MIN TYP MAX 0.01 to 3.15 10 to 450 36 36 40 UNITS GHz MHz dB dB dB (Test circuit shown in Figure 3 for 2.5GHz application) VCC = 3V DC, LNA: fLNA_IN = 2.5GHz, Mixer: fMIX_IN = 2.5GHz, fLO = 2.22GHz, PLO = – 10dBm, TA = 25°C, unless otherwise noted. SYMBOL PARAMETER LNA High Gain: EN = 1.35V, GS = 1.35V Forward Gain Reverse Gain (Isolation) Noise Figure Input Return Loss Output Return Loss Input 1dB Compression Input 3rd Order Intercept LNA Low Gain: EN = 1.35V, GS = 0.3V Forward Gain Reverse Gain (Isolation) Noise Figure Input 1dB Compression Input 3rd Order Intercept Mixer: EN = 1.35V, GS = 1.35V Conversion Gain SSB Noise Figure Input P1dB Input 3rd Order Intercept LO-IF Isolation LO-RF Isolation RF-LO Isolation CONDITIONS MIN TYP 13.5 –35 4 12 15 –15 –3.5 –14 –39 19 –1 8 5 9.5 –11 – 2.5 33 37 32 MAX UNITS dB dB dB dB dB dBm dBm dB dB dB dBm dBm dB dB dBm dBm dB dB dB Terminated 50Ω Source No External Matching With External Matching Two Tone Test, ∆f = 2MHz Two Tone Test, ∆f = 2MHz Terminated 50Ω Source Two Tone Test, ∆f = 2MHz VCC = 3V DC, TA = 25°C (Note 4) SYMBOL PARAMETER Power Supply VCC Supply Voltage ICC HG Rx High Gain Mode ICC LG Rx Low Gain Mode ICC Off Shutdown Current IEN Enable Current IGS Gain Select Current CONDITIONS MIN TYP 1.8 to 5.25 23 18 2 21 21 MAX UNITS V mA mA µA µA µA EN = 1.35V, GS = 1.35V EN = 1.35V, GS = 0.3V EN = 0.3V, GS = 0.3V EN = 1.35V (Note 5) GS = 1.35V (Note 6) 33 31 25 Note 1: Absolute Maximum Ratings are those values beyond which the life of the device may be impaired. Note 2: LO Absolute Maximum Ratings apply for each LO pin separately. Note 3: Component values listed in Figure 3 for 1.8GHz evaluation board were used to guarantee 1.8GHz performance. Note 4: Specifications over the –40°C to 85°C operating temperature range are assured by design, characterization and correlation with statistical process controls. Note 5: When EN ≤ 0.3V, enable current is