LTC1957-2EMS#TR Linear Technology, LTC1957-2EMS#TR Datasheet

IC RF PWR CONTROLLR DUAL 10-MSOP

LTC1957-2EMS#TR

Manufacturer Part Number
LTC1957-2EMS#TR
Description
IC RF PWR CONTROLLR DUAL 10-MSOP
Manufacturer
Linear Technology
Datasheet

Specifications of LTC1957-2EMS#TR

Rf Type
Cellular, GSM, GPRS, PCS, Wireless Modem, TDMA
Frequency
850MHz ~ 2GHz
Features
Dual Output
Package / Case
10-MSOP, Micro10™, 10-uMAX, 10-uSOP
Operating Supply Voltage (typ)
3.3/5V
Operating Supply Voltage (min)
2.7V
Operating Supply Voltage (max)
6V
Operating Temp Range
0C to 70C
Operating Temperature Classification
Commercial
Mounting
Surface Mount
Pin Count
10
Lead Free Status / RoHS Status
Contains lead / RoHS non-compliant
Other names
LTC1957-2EMSTR

Available stocks

Company
Part Number
Manufacturer
Quantity
Price
Company:
Part Number:
LTC1957-2EMS#TRLTC1957-2EMS
Manufacturer:
LT
Quantity:
10 000
Company:
Part Number:
LTC1957-2EMS#TRLTC1957-2EMS#PBF
Manufacturer:
LINEAR/凌特
Quantity:
20 000
Company:
Part Number:
LTC1957-2EMS#TRPBF
Manufacturer:
MOTOROLA
Quantity:
6 242
Company:
Part Number:
LTC1957-2EMS#TRPBF
Manufacturer:
LINEAR/凌特
Quantity:
20 000
FEATURES
APPLICATIO S
TYPICAL APPLICATIO
Dual Band RF Power Amplifier Control (LTC1957-2)
Internal Schottky Diode Detector with Improved
Dynamic Range vs the LTC1757A
Wide Input Frequency Range: 850MHz to 2GHz
Autozero Loop Cancels Offset Errors and
Temperature Dependent Offsets
Wide V
Allows Direct Connection to Battery
RF Output Power Set by External DAC
Fast Acquire After Transmit Enable
Internal Frequency Compensation
Rail-to-Rail Power Control Outputs
Power Control Signal Overvoltage Protection
Low Operating Current: 1mA
Very Low Shutdown Current: < 1 A
Available in a 8-Pin MSOP Package (LTC1957-1)
and 10-Pin MSOP (LTC1957-2)
Pin Compatible with the LTC1757A-X
Improved Start Voltage Accuracy and Range
Improved PCTL Input Filtering
Single and Dual Band GSM/GPRS Cellular Telephones
PCS Devices
Wireless Data Modems
U.S. TDMA Cellular Phones
IN
Range: 2.7V to 6V
U
Li-Ion
V
IN
68
33pF
SHDN
BSEL
U
1
2
3
4
5
LTC1957-2 Dual Band Cellular Telephone Transmitter
V
RF
SHDN
BSEL
GND
IN
LTC1957-2
DAC
TXEN
PCTL
V
V
V
PCA
PCB
Controllers with 40dB Dynamic Range
CC
10
9
8
7
6
TXEN
1.8GHz /1.9GHz
900MHz
DESCRIPTIO
The LTC
power amplifiers operating in the 850MHz to 2GHz range.
The input voltage range is optimized for operation from
a single lithium-ion cell or 3 NiMH. Several functions
required for RF power control and protection are inte-
grated in one small 10-pin MSOP package, thereby
minimizing PCB area.
The LTC1957-1 is a 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.
RF power is controlled by driving the RF amplifier power
control pins and sensing the resultant RF output power
via a directional coupler. The RF sense voltage is peak
detected using an on-chip Schottky diode. This detected
voltage is compared to the DAC voltage at the PCTL pin
to control the output power. The RF power amplifier is
protected against high supply current and high power
control pin voltages.
Internal and external offsets are cancelled over tempera-
ture by an autozero control loop, allowing accurate low
power programming. The shutdown feature disables the
part and reduces the supply current to < 1 A.
, LTC and LT are registered trademarks of Linear Technology Corporation.
Single/Dual Band RF Power
RF PA
RF PA
®
1957-2 is a dual band RF power controller for
DIRECTIONAL
LTC1957-1/LTC1957-2
COUPLER
PCA
U
) is provided. The LTC1957-1 can
50
DIPLEXER
1957 TA01
1

Related parts for LTC1957-2EMS#TR

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 ...

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