LTC1479 LINER [Linear Technology], LTC1479 Datasheet
LTC1479
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LTC1479 Summary of contents
Page 1
... The LTC1479 directs power from up to two battery packs and a DC power source to the input of the main system switching regulator. It works in concert with related LTC power management products (e ...
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... Regulator Output Current .............................. 1mA CCP + V Output Current .................................................. 1mA V Regulator Output Current ............................ 100 A GG Operating Temperature LTC1479CG ............................................. LTC1479IG ........................................ – Junction Temperature........................................... 125 C Storage Temperature Range ................. – 150 C Lead Temperature (Soldering, 10 sec).................. 300 C DC ELECTRICAL CHARACTERISTICS V = 25V 16V 12V, T DCIN ...
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... Each Switch Tested Independently (Modes 5, 6) Each Switch Tested Independently (Mode 1) All Digital Inputs (Mode 1) All Digital Inputs (Mode 1) All Digital Inputs DIGINX (Mode (Note 3) DIGINX (Mode (Note 4) DIGINX LTC1479 MIN TYP MAX UNITS 1.190 1.215 1.240 ...
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... LTC1479 AC ELECTRICAL CHARACTERISTICS V = 25V 16V 12V, T DCIN BAT1 BAT2 SYMBOL PARAMETER t Gate A/B Turn-On Time ONGA/GB t Gate C/D Turn-On Time ONGC/GD t Gate E/F Turn-On Time ONGE/GF t Gate A/B Turn-Off Time OFFGA/GB t Gate C/D Turn-Off Time OFFGC/GD t Gate E/F Turn-Off Time OFFGE/GF t Gate G/H Turn-On Time ONGG/GH t Gate G/H Turn-Off Time ...
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... G04 6.5 6.0 5.5 5.0 4.5 4.0 3.5 3.0 50 100 125 75 – 50 1479 G06 LTC1479 BAT2 Supply Current 350 MODE 6 NO OTHER POWER 300 250 200 150 100 BAT2 SUPPLY VOLTAGE (V) 1479 G02 V Supply Voltage GG MODE 1 ...
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... V (Pin 36): Supply Input. This input supplies power to BKUP the LTC1479 when in the backup mode of operation bypass capacitor should be connected to the V close as possible if there is no larger backup supply capacitor within 2". Internal Power Supply Pins V (Pin 20): Power Supply Output ...
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... A pull-up current source and allows the P to select which battery is connected to the system and the battery monitor comparator input. Battery 1 is selected with a logic high on this input and battery 2 is selected with a logic low. LTC1479 7 ...
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... LTC1479 W BLOCK DIAGRAM DCIN GA DCIN DCDIV MONITOR DRIVERS BAT1 BAT2 DCIN + CCP REGULATOR V CC & BIAS GENERATOR SWITCHING REGULATOR V CCP CCP BAT2 BAT1 BATSEL V CHGSEL BAT 8 SAB GB GC SCD GD GE SEF GF SW A/B SW C/D SW E/F GATE GATE GATE ...
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... MODE 4 DC OPERATION DC OPERATION BAT2 DISCONNECTED BAT2 CHARGING Backup and DC Restoration Timing MODE 9 MODE 10 NO POWER DC RESTORED (NO BACKUP) (THREE DIODE MODE) (24.3V) (0V) LTC1479 MODE 5 MODE 6 BAT1 OPERATION BAT2 OPERATION (16V) (12V) 1479 TD01 MODE 11 MODE 12 DC RECONNECTED THREE DIODE MODE (SW A/B ON) (25V) (24 ...
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... LTC1479 U OPERATION The LTC1479 is responsible for low-loss switching at the “front end” of the power management system, where up to two battery packs and a DC power source can be indiscriminately connected and disconnected. Smooth switching between input power sources is accomplished with the help of low-loss N-channel switches driven by ...
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... Interface to Companion Microprocessor A companion P must be used in conjunction with the LTC1479 to provide overall control of the power manage- ment system. The LTC1479 communicates with the P by means of five logic inputs and two logic outputs as described in Table 1. Table 1. LTC1479 P Interface Inputs and Outputs ...
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... Figure conceptual block diagram which illustrates the main features of an LTC1479 dual battery power management system, starting with the three main power sources and ending at the system DC/DC regulator. Switches SW A/B, SW C/D and SW E/F direct power from ...
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... Start” Initial Condition The LTC1479 is designed to start in the “3- diode” mode when all five logic inputs are low— when no power is available (including the backup system). A 100k resistor from the 3DM input to ground ensures that this input is low during a “ ...
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... F05 Figure 5. DC Monitor Resistor Divider BATSEL SWITCH CONTROL LOGIC V BAT LOBAT + 1.215V BDIV – LTC1479 1479 F06 Figure 6. Battery Monitor Resistor Divider is then selected according to DC2 V GOOD – 1 1.215V pin and therefore to the top BAT = 121k so that approxi selected according to the ...
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... Because the three input supply diodes and regulator output diode are built into the LTC1479, only three external components are required by the shown in Figure 7. ...
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... LT1304 monitors the input supply voltage and activates D1 CONVERTER MBR0530 when it drops below 6V. Power for the DCIN and battery monitors and the logic supply in the LTC1479 is then obtained from the output of R4 390k the LT1304 step-up regulator Charger System Interface ...
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... N-channel switch pairs The charging battery voltage is simultaneously connected through the CHGMON switch in the LTC1479 to the top of the charger voltage resistor divider, R4 and R5, for constant voltage charging. (See the LT1510 data sheet for further detail.) ...
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... Ps. Further, because of the direct interface via the five logic inputs and the two logic outputs, there is virtually no latency (i.e. time delay) between the P and the LTC1479. In this way, time critical decisions can be made by the P without the inherent delays associated with bus protocols, etc ...
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... SFB IN CMDSH INTV SGND OSENSE C9, 100pF 7 10 – SENSE PGND C10 SENSE V 100pF 10k 1% LTC1479 DC INPUT 330 (FROM AC ADAPTER 100pF 0.1% R2 76.8k 0.1% C15 + 22 F 35V Q1 2 Si4412DY C12 0 0.025 C13 D1* 0.33 F CMDSH-3 ...
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... U U APPLICATIONS INFORMATION Interfacing to the Battery Pack The LTC1479 is designed to work with virtually any battery pack chemistry or cell count, as long as the battery pack operating voltage range is somewhere between 6V and 28V. This permits great flexibility in system design. The low-battery threshold is adjustable and can be set anywhere between 6V and 28V. ...
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... 50V R CM1 100k CERAMIC R R4 PROG R5 11k 100k 300 2N7002 1 F (CHARGER OUTPUT) LTC1479 (BOLD LINES INDICATE HIGH CURRENT PATHS) D1 ROHM L2** R8 MBR0530 DTA144E 10 H 10k + C5 NiCD 0.1 F CELL Q2 2N7002 LBO FB LT1304 7 D5 ...
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... Dual Li-Ion Battery Power Management System R SENSE 0.033 Si4936DY FROM Si4936DY DC/ – GC SCD GD GE SEF GF SENSE SENSE V BKUP LTC1479 BATSEL CHGSEL DCINGOOD 3DM BATDIS DCIN/BAT CHGMON LOBAT 50V CERAMIC R PROG R6 R5 3.83k 300 ...
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... BATDIS DCIN/BAT CHGMON LOBAT 50V CERAMIC R PROG R6 4.93k 500 0. 2N7002 (CHARGER OUTPUT) LTC1479 (BOLD LINES INDICATE HIGH CURRENT PATHS) D1 ROHM L2** R12 MBR0530 DTA144E 10 H 10k + C5 NiCD 0.1 F CELL Q2 2N7002 LBO FB LT1304 7 D5 ...
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... LTC1479 PACKAGE DESCRIPTION 0.205 – 0.212** (5.20 – 5.38) 0.005 – 0.009 0.022 – 0.037 (0.13 – 0.22) (0.55 – 0.95) * DIMENSIONS DO NOT INCLUDE MOLD FLASH. MOLD FLASH SHALL NOT EXCEED 0.006" (0.152mm) PER SIDE ** DIMENSIONS DO NOT INCLUDE INTERLEAD FLASH. INTERLEAD FLASH SHALL NOT EXCEED 0.010" (0.254mm) PER SIDE ...