LTC1957-2EMS#TR Linear Technology, LTC1957-2EMS#TR Datasheet
LTC1957-2EMS#TR
Specifications of LTC1957-2EMS#TR
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LTC1957-2EMS#TR Summary of contents
Page 1
... RF power control and protection are inte- grated in one small 10-pin 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 ...
Page 2
... 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 ...
Page 3
... 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 ...
Page 5
... RF PA 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 100 ...
Page 6
... For example, V PCB PCA a 900MHz channel and V a 1.8GHz/1.9GHz channel. PCB BSEL must be established before the part is enabled. The LTC1957-1 can be used to drive a single RF channel or dual channel with integral multiplexer Control Amplifier The control amplifier supplies the power control voltage to the RF power amplifier. A portion (typically – ...
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
... RF pin directional coupler is used recom- mended that an external 68 termination resistor be connected between the RF coupling capacitor (33pF), and ground at the side connected to the directional coupler. If the termination is placed at the LTC1957 RF pin, then the 68 resistor must be connected referenced Termination components should be IN placed adjacent to the LTC1957 ...
Page 9
... Loop voltage losses supplied by the directional coupler will improve phase margin. The larger the directional coupler loss the more stable the loop will become. How- ever, larger losses reduce the RF signal to the LTC1957 LTC1957 and detector performance may be degraded at low power PTCL levels ...
Page 10
... RF input voltage and frequency. The LTC1957 unity gain bandwidth specified in the data sheet assumes that the net voltage gain contributed by the RF power amplifier and directional coupler is unity. The ...
Page 11
... Bode plot. A low frequency AC SPICE model of the LTC1957 power control- ler is included to better determine pole and zero interac- tions. The user can apply external gains and poles to determine bandwidth and phase margin ...
Page 12
... VPCTLO, VRF, Adjust EFB gain to reflect external gain, currently set at 3X** *EFB RF 0 VPCA VIN 3 VIN VIN *VPCTLO PCTL **Open loop connections, comment-out EFB, VIN and VPCTLO** VPCTLO PCTL VRF **Add AC statement and print statement as required** .AC DEC 50 100 1E7 .END Figure 7. LTC1957 Low Frequency AC SPICE Model ...
Page 13
... U U APPLICATIO S I FOR ATIO W U LTC1957-1/LTC1957-2 13 ...
Page 14
... 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 ...
Page 15
... 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 ...
Page 16
... P-P 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 ...