ltc1758-2 Linear Technology Corporation, ltc1758-2 Datasheet
ltc1758-2
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ltc1758-2 Summary of contents
Page 1
... PAs such as the Philips BGY280, Conexant RM009/ CX77302, Anadigics AWT6102/AWT6107 and the Hitachi PF08107/PF08123B. The LTC1758 single output RF power controller that is identical in performance to the LTC1758-2 except that one output (V be used to drive a single RF or dual channel module with integral multiplexer. This part is available in an 8-pin MSOP package ...
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... IN = 100pF (Note 5) LOAD = 400 (Note 8) LOAD = 100pF (Note 3) LOAD = 2V Step PCTL = 100pF (Note 9) LOAD TOP VIEW ORDER PART 10 V NUMBER PCA 8 V PCB 7 TXEN LTC1758-2EMS 6 PCTL MS10 PART MARKING = 160 C/W JA LTSM MIN TYP MAX 2 1.6 1.1 1.7 2.2 90 150 0 0.1 V – 0.28 IN 2.7 2 ...
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... Note 1: Absolute Maximum Ratings are those values beyond which the life of a device may be impaired. Note 2: The LTC1758-1 and LTC1758-2 are guaranteed to meet performance specifications from Specifications over the – operating temperature range are assured by design, characterization and correlation with statistical process controls. ...
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... When TXEN is low and SHDN is high the part is in the autozero mode. This input has an internal 150k resistor to ground. V (Pin 8): (LTC1758-2 Only) Power Control Voltage PCB Output. This pin drives an external RF power amplifier power control pin. The maximum load capacitance is 100pF ...
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... Li-Ion AUTOZERO – 50mV FILTER – + ICL 33k + RFDET – 22k 33k 22k COMPRESSION 22k XMT AUTOZERO 150k TXEN PCTL 7 6 LTC1758-1/LTC1758 1.8GHz/1.9GHz 50 TXENB PA ADJUSTABLE + PB CAMP – 400 A 140k VPC g 110k m 1.2V 1.2V BG1 1.2V BANDGAP ADJUSTABLE 12 PB TSDB ...
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... PCA PCB Band Selection The LTC1758-2 is designed for dual band operation. The BSEL pin will select output V PCA V when high. For example, V PCB PCA a 900MHz channel and ...
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... The RF amplifier will then start to turn PCA on. The feedback signal from the directional coupler and the output power will be detected by the LTC1758-2 at the RF pin. The loop closes and the amplifier output tracks the DAC voltage ramping at PCTL. The RF power output will then follow the programmed power profile from the DAC ...
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... U APPLICATIO S I FOR ATIO LTC1758-1 Description The LTC1758-1 is identical in performance to the LTC1758-2 except that only one control output (V available. The LTC1758-1 can drive a single band (850MHz to 2000MHz dual RF channel module with an internal mulitplexer. Several manufacturers offer dual RF channel modules with an internal mulitplexer. ...
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... The range of decoupling capacitor values is typically 1nF to 3 Poor layout techniques associated with the directional coupler area may result in high frequency signals bypass- ing the coupler. This could result in stability problems due to the reduction in the coupler loss. LTC1758-1/LTC1758-2 conditions. The oscillation fre- SWR 9 ...
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... LTC1758-1/LTC1758 APPLICATIO S I FOR ATIO Determining External Loop Gain and Bandwidth The external loop voltage gain contributed by the RF chan- nel and directional coupler network should be measured in a closed loop configuration. A voltage step is applied to PCTL and the change in V (or V PCA detected voltage is 0.6 • ...
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... It should be remembered that models are a simplification of the actual circuit. CONTROLLED RF OUTPUT POWER 1758 F05 Figure 6. SPICE Model Open Loop Gain and Phase Characteristics from LTC1758-1/LTC1758-2 80 120 110 LOAD C = 33pF ...
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... LTC1758-1/LTC1758 APPLICATIO S I FOR ATIO *LTC1758 Low Frequency AC Spice Model* GIN1 ND2 0 ND1A IFB 100E-6 GX3 ND6 0 0 ND4 1E-6 GX4 ND7 0 0 ND6 1E-6 GX1 ND3 0 0 ND2 1E-6 GX2 ND4 0 0 ND3 1E-6 GX5 ND10 0 0 ND9 1E-6 GX8 ND14 0 0 ND12 1E-6 ...
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... U U APPLICATIO S I FOR ATIO W U LTC1758-1/LTC1758-2 13 ...
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... LTC1758-1/LTC1758-2 PACKAGE DESCRIPTIO 0.007 (0.18) 0.021 0.006 (0.53 0.015) * DIMENSION DOES NOT INCLUDE MOLD FLASH, PROTRUSIONS OR GATE BURRS. MOLD FLASH, PROTRUSIONS OR GATE BURRS SHALL NOT EXCEED 0.006" (0.152mm) PER SIDE ** DIMENSION DOES NOT INCLUDE INTERLEAD FLASH OR PROTRUSIONS. INTERLEAD FLASH OR PROTRUSIONS SHALL NOT EXCEED 0.006" (0.152mm) PER SIDE ...
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... Plastic MSOP (Reference LTC DWG # 05-08-1661) 0.118 0.004* (3.00 0.102) 0.193 0.006 (4.90 0.15) 0.043 (1.10) MAX 0 – 6 TYP SEATING PLANE 0.007 – 0.011 0.021 0.006 (0.17 – 0.27) (0.53 0.015) LTC1758-1/LTC1758 0.118 0.004** (3.00 0.102 0.034 (0.86) REF 0.005 0.002 (0.13 0.05) 0.0197 MSOP (MS10) 1100 (0.50) ...
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... LTC1758-1/LTC1758-2 U TYPICAL APPLICATIO S 68 33pF Li-Ion 3 SHDN 4 Dual Band Cellular Telephone Transmitter Without Current Limiting 68 33pF LTC1758 Li-Ion RF 3 SHDN SHDN 4 GND DAC RELATED PARTS PART NUMBER DESCRIPTION LTC1261 Regulated Inductorless Voltage Inverter LTC1550/LTC1551 Low Noise Inductorless Voltage Inverter ...