ltc1957-2 Linear Technology Corporation, ltc1957-2 Datasheet
ltc1957-2
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ltc1957-2 Summary of contents
Page 1
... MSOP package, thereby minimizing PCB area. The LTC1957 single output RF power controller that is identical in performance to the LTC1957-2 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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... PCA 100pF (Note 5) LOAD = 400 (Note 8) LOAD = 100pF (Note 3) LOAD = 2V Step PCTL = 100pF (Note 9) LOAD ORDER PART NUMBER TOP VIEW LTC1957-2EMS PCA 8 V PCB 7 TXEN 6 PCTL MS10 PART MARKING = 160 C/W LTRJ JA MIN TYP MAX 2 1.6 1.1 1.7 2.2 90 150 0 0 ...
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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 LTC1957-1 and LTC1957-2 are guaranteed to meet performance specifications from Specifications over the – operating temperature range are assured by design, characterization and correlation with statistical process controls. ...
Page 4
... 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): (LTC1957-2 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 LTC1957-1/LTC1957 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 LTC1957-2 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 ...
Page 7
... The RF amplifier will then start to turn on. The feedback signal from the directional coupler and the output power will be detected by the LTC1957-2 at the RF pin. The loop closes and the amplifier output tracks the DAC voltage ramping at PCTL. The RF power output ...
Page 8
... U APPLICATIO S I FOR ATIO LTC1957-1 Description The LTC1957-1 is identical in performance to the LTC1957-2 except that only one control output (V available. The LTC1957-1 can drive a single band (880MHz 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. LTC1957-1/LTC1957-2 conditions. The oscillation fre- SWR 9 ...
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... LTC1957-1/LTC1957 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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... In no event will Linear Technology be liable for special, collat- eral, incidental or consequential damages in connection with or arising out of the use of this model. It should be remembered that models are a simplification of the actual circuit. LTC1957-1/LTC1957-2 80 180 LOAD ...
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... LTC1957-1/LTC1957 APPLICATIO S I FOR ATIO *LTC1957 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 LTC1957-1/LTC1957-2 13 ...
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... LTC1957-1/LTC1957-2 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) LTC1957-1/LTC1957 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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... Complete Pulse Charger for 1-Cell Li-Ion Battery Complete Linear Charger for 1- and 2-Cell Li-Ion Battery Only Two External Components, Allows Charge Current Monitoring for Termination Single/Dual Channel RF Power Controllers (Lower Bandwidth Version of LTC1957-1/LTC1957- 100mA, Low Noise OUT 2MHz Constant Frequency, I ...