LTC1960CG Linear Technology, LTC1960CG Datasheet
LTC1960CG
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LTC1960CG Summary of contents
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... The LTC1960’s 5mm × 7mm 38-pin QFN and 36-pin nar- row SSOP packages allow implementation of a complete SBS-compliant dual battery system while consuming minimum PCB area. L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and No R and PowerPath are trademarks of Linear Technology Corporation. All other SENSE trademarks are the property of their respective owners ...
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... CLP CSP 23 22 CSN 21 MOSI MISO 20 19 SCK THE EXPOSED PAD (PIN 39) IS GND. MUST BE SOLDERED TO THE PCB PART MARKING* PACKAGE DESCRIPTION LTC1960CG 36-Lead Plastic SSOP 1960 38-Lead (5mm × 7mm) Plastic QFN http://www.linear.com/leadfree/ http://www.linear.com/tapeandreel/ TOP VIEW SCP SET I ...
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ELECTRICAL CHARACTERISTICS temperature range (Note 7), otherwise specifications are at T SYMBOL PARAMETER Supply and Reference DCIN Operating Range I DCIN Operating Current CH Battery Operating Voltage Range Battery Drain Current V Diodes Forward Voltage: PLUS V DCIN to V ...
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LTC1960 ELECTRICAL CHARACTERISTICS temperature range (Note 7), otherwise specifications are at T SYMBOL PARAMETER DACs I IDAC Resolution RES IDAC Pulse Period: t Normal Mode IP t Low Current Mode ILOW V VDAC Resolution RES V VDAC Granularity STEP V ...
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ELECTRICAL CHARACTERISTICS temperature range (Note 7), otherwise specifications are at T SYMBOL PARAMETER t Gate B1I/B2I/DCI Turn-On Time ONPI t Gate B1I/B2I/DCI Turn-Off Time OFFPI V Input Gate Clamp Voltage PONI GB1I GB2I GDCI V Input Gate Off Voltage POFFI ...
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LTC1960 TYPICAL PERFORMANCE CHARACTERISTICS Battery Drain Current (BAT1 Selected) 250 T = 25°C A 240 230 220 210 200 190 180 170 160 150 BAT1 VOLTAGE (V) 1960 G01 Charger Efficiency 100 ...
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TYPICAL PERFORMANCE CHARACTERISTICS Voltage Accuracy 100 DCIN = 24V T = 25° 100mA LOAD –25 –50 –75 –100 1250 250 450 650 850 1050 1450 VDAC VALUE 1960 G10 Dual vs Sequential Discharge ...
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LTC1960 PIN FUNCTIONS (G/UHF) Input Power Related SCN (Pin 4/Pin 30): PowerPath Current Sensing Negative Input. This pin should be connected directly to the “bottom” (output side) of the sense resistor, R three PowerPath switch pairs, for detecting short-circuit current ...
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PIN FUNCTIONS (G/UHF) TGATE (Pin 32/Pin 21): Drives the top external MOSFET of the battery charger buck converter. SCH1 (Pin 33/Pin 22), SCH2 (Pin 36/Pin 25): Charger MUX N-Channel Switch Source Returns. These two pins are connected to the sources ...
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... LTC1960 BLOCK DIAGRAM (LTC1960CG Pin Numbers Shown) CHARGE DCIN PUMP ON GCH1 34 – + SCH1 33 ON GCH2 35 – + SCH2 36 BAT1 3 CHGMON 2 BAT2 V 1 SCN PLUS REGULATOR 16 GND DCIN SET OSCILLATOR LOW DROP BGATE T DETECT ON BOOST 31 TGATE BGATE 27 PGND 0.4m DCIN m + 100mV CL1 – ...
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TEST CIRCUIT BAT1 TIMING DIAGRAM SSB t LD SCK t su MOSI t A MISO + V REF EA – CHGMON BAT2 V SET + – SPI Timing Diagram t CYC BIT 7 t ...
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LTC1960 OPERATION (Refer to Block Diagram and Typical Application) OVERVIEW The LTC1960 is composed of a battery charger controller, charge MUX controller, PowerPath controller, SPI inter- face, a 10-bit current DAC (IDAC) and 11-bit voltage DAC (VDAC). When coupled with ...
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OPERATION 1-Byte SPI Write Format: MOSI MISO Charger Write Address: Charger Write Data: PowerPath Write Address: PowerPath Write Data: 2-Byte SPI Write Format: MOSI MISO IDAC Write Address: IDAC Data Bits D9-D0: IDAC Data Bit D10 : VDAC Write Address: ...
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LTC1960 OPERATION 2-Byte SPI Read Format: bit 7........byte 1.......bit 0 MOSI MISO Status Address: A[2:0] = b010 Status Read Data LOW_POWER (Low ...
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OPERATION Battery Charger Controller The LTC1960 charger controller uses a constant off-time, current mode step-down architecture. During normal operation, the top MOSFET is turned on each cycle when the oscillator sets the SR latch and turned off when the main ...
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LTC1960 OPERATION Dual Charging Note that the charge MUX switch drivers will operate together to allow both batteries to be charged simultane- ously. If both charge MUX switch drivers are enabled, only the battery with the lowest voltage will be ...
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OPERATION bit is set in the status register. This is a three-strikes-and- you’re-out process which is intended to debounce the PowerPath PF indicator. The power-fail counter is reset by a PowerPath SPI write. Short-Circuit Protection Short-circuit protection operates in both ...
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LTC1960 OPERATION The Current DAC Block The current DAC is a delta-sigma modulator which controls the effective value of an internal resistor, R used to program the maximum charger current. Figure simplified diagram of the DAC operation. ...
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APPLICATIONS INFORMATION Automatic Current Sharing In a dual parallel charge configuration, the LTC1960 does not actually control the current flowing into each individual battery. The capacity, or amp-hour rating, of each battery determines how the charger current is shared. This ...
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... Extending System to More Than Two Batteries The LTC1960 can be extended to manage systems with more than three sources of power. Contact Linear Technology Applications Engineering for more information. Charging Depleted Batteries Some batteries contain internal protection switches that disconnect a load if the battery voltage falls below what is considered a reasonable minimum ...
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APPLICATIONS INFORMATION ∆I exceed 0.6(I ) due to limits imposed by IREV and L MAX CA1. Remember the maximum ∆I mum input voltage. In practice, 10µH is the lowest value recommended for use. Charger Switching Power MOSFET and Diode Selection ...
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LTC1960 APPLICATIONS INFORMATION V /I Capacitors SET SET Capacitor C7 is used to filter the delta-sigma modulation frequency components to a level which is essentially DC. Acceptable voltage ripple about 10mV SET the period of the delta-sigma ...
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APPLICATIONS INFORMATION EMI considerations usually make it desirable to minimize ripple current in the battery leads, and beads or inductors may be added to increase battery impedance at the 300kHz switching frequency. Switching ripple current splits be- tween the battery ...
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LTC1960 APPLICATIONS INFORMATION I is the fixed drive current into the gate from the DRIVE LTC1960 and “t” is the time it takes to move that charge to a new state and change the MOSFET conduction mode. Hence, time is ...
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PACKAGE DESCRIPTION 7.8 – 8.2 0.42 ±0.03 RECOMMENDED SOLDER PAD LAYOUT 5.00 – 5.60** (.197 – .221) 0.55 – 0.95 0.09 – 0.25 (.0035 – .010) (.022 – .037) NOTE: 1. CONTROLLING DIMENSION: MILLIMETERS MILLIMETERS 2. DIMENSIONS ARE IN (INCHES) ...
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LTC1960 PACKAGE DESCRIPTION 5.50 ± 0.05 4.10 ± 0.05 3.00 REF APPLY SOLDER MASK TO AREAS THAT ARE NOT SOLDERED 5.00 ± 0.10 PIN 1 TOP MARK (SEE NOTE 6) 7.00 ± 0.10 NOTE: 1. DRAWING CONFORMS TO JEDEC PACKAGE ...
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... Updated equation in “Calculating IC Power Dissipation” section Updated Typical Application Information furnished by Linear Technology Corporation is believed to be accurate and reliable. However, no responsibility is assumed for its use. Linear Technology Corporation makes no representa- tion that the interconnection of its circuits as described herein will not infringe on existing patent rights. LTC1960 ...
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... VID LTC1759 SMBus Controlled Smart Battery Charger LT1769 2A Battery Charger 28 Linear Technology Corporation 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 ● (LTC1960CG Pin Numbers Shown) Dual Battery Selector and 4A Charger C2 1µF 100 Q1 C8 0.1µF LTC1960 Q2 1 ...