ltc4101 Linear Technology Corporation, ltc4101 Datasheet
ltc4101
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ltc4101 Summary of contents
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... DESCRIPTIO ® The LTC charging solution that dramatically simplifies construc- tion of an SBS compliant system. The LTC4101 imple- ments a Level 2 charger function whereby the charger can be programmed by the battery or by the host. A SafetySignal on the battery being charged is monitored for tempera- ture, connectivity and battery type information. The SMBus ...
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... THA 10 15 THB LIM LIM G PACKAGE 24-LEAD PLASTIC SSOP = 125°C, θ 90°C/W JMAX JA LTC4101EG http://www.linear.com/leadfree unless otherwise noted. (Note 4) MIN TYP MAX UNITS ● –1.1 1.1 ● –1.3 1.3 –2 6 ● –3 7 ● 3 5.5 ● ...
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... BGATE C = 3000pF, 10% to 90% LOAD C = 3000pF, 10% to 90% LOAD C = 3000pF, 10% to 90% LOAD C = 3000pF, 10% to 90% LOAD - –1µA TGATE TGATE I = 1µA TGATE LTC4101 = 4V unless otherwise noted. (Note 4) BAT MIN TYP MAX – 1.4V –40 = 1.4V 40 1.5 ● 93 100 107 1.4V 36 ● 102 107 110 ● ...
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... LTC4101 ELECTRICAL CHARACTERISTICS temperature range, otherwise specifications are at T SYMBOL PARAMETER AC Present Comparator V DCDIV Threshold ACP DCDIV Hysteresis DCDIV Input Bias Current ACP V OH ACP V OL DCDIV to ACP Delay SafetySignal Decoder SafetySignal Trip (RES_COLD/RES_OR) SafetySignal Trip (RES_IDEAL/RES_COLD) R SafetySignal Trip (RES_HOT/RES_IDEAL) SafetySignal Trip (RES_UR/RES_HOT) ...
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... Maximum Rating condition for extended periods may affect device reliabilty and lifetime. Note 2: See Test Circuit. Note 3: Does not include tolerance of current sense resistor. Note 4: The LTC4101E is guaranteed to meet performance specifications from 0°C to 85°C. Specifications over the –40°C to 85°C operating The ● ...
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... LOAD STATE RECONNECT DISCONNECT LOAD CURRENT = 1A, 2A, 3A DCIN = 12V V = 4.2V FLOAT 4101 G04 SMBus Accelerator Operation 200pF BUS 5V LTC4101 R = 15k PULLUP 0V 1µs/DIV 25°C unless otherwise noted. A Output Voltage vs Output Current 0 –0.5 –1.0 –1.5 –2.0 –2.5 –3.0 –3.5 – ...
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... SMBALERT (Pin 7): Active Low Interrupt Output to Host (referred to as the SMBALERT signal in the SMBus Revi- sion 1.1 specification). Signals host that there has been a change of status in the charger registers and that the host should read the LTC4101 status registers to determine 20V DCIN = 9V – ...
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... SafetySignal is 1nF (see Figure 4). A series resistor 1130Ω needs to be connected between this pin and the battery’s SafetySignal for this circuit to work correctly. V (Pin 17): Power Supply Input for the LTC4101 Digital DD Circuitry. Bypass this pin with 0.1µF. Typically between 3.3V and 5V ...
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... ON – 1.19V S I CMP Q R PWM I LOGIC 100mV Ω 1. CL1 – 5.8V CLP V DD 10µA SMBus INTERFACE AND CONTROL THERMISTER INTERFACE Figure 2. LTC4101 3k BAT – 11.67µA R SENSE – 20µF 3k CA1 CSP + 21 CSP 9k BUFFERED I TH ÷5 + – – REV 17mV + – ...
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... TC01 U OPERATIO Overview (Refer to Block Diagram) The LTC4101 is composed of a battery charger section, a charger controller, a 10-bit DAC to control charger cur- rent, an 11-bit DAC to control charger voltage, a SafetySignal decoder, limit decoder and an SMBus controller block battery is present, the SafetySignal decoder indicates a RES_OR condition and charging is disabled by the charger controller (CHGEN = Low) ...
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... TH SMBus Interface 4101 F01 All communications over the SMBus are interpreted by the SMBus interface block. The SMBus interface is a SMBus slave device. All internal LTC4101 registers may be up- resets the SR CMP dated and accessed through the SMBus interface, and . turn ...
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... ChargerMode() ('h12) Description: The SMBus Host uses this command to set the various charger modes. The default values are set to allow a Smart Battery and the LTC4101 to work in concert without requiring an SMBus Host. Purpose: Allows the SMBus Host to configure the charger and change the default modes. This is a write only func- tion, but the value of the “ ...
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... CHARGING_CURRENT[15:0] Permitted Unsigned integer representing current in mA Values 8'h15 Value CHARGING_VOLTAGE[15:0] Permitted Unsigned integer representing voltage in mV Values 8'h16 Control Permitted Values 1/0 1/0 1/0 1/0 8'h3C Register Reserved LTC4101's Version Identification Permitted Ignored 1/0 Values Return Values 1 N/A Status Not Supported Return Values ...
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... ACP setting of the ALARM_INHIBITED will activate the LTC4101 SMBALERT pull-down. POWER_FAIL bit is set if the LTC4101 does not have sufficient DCIN voltage to charge the battery external device is pulling the CHGEN input signal low. Charging is disabled whenever this bit is set. The setting ...
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... Purpose: This function allows the SMBus Host to determine if the battery charger is an LTC4101. Identi- fying the manufacturer and version of the Smart Battery Charger permits software to perform tasks specific to a given charger. The LTC4101 also provides a means of disabling the LOWI current mode of the I • SMBus Protocol: Write Word. : ...
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... The host may control charging by disabling the Smart Battery’s ability to transmit ChargingCurrent() and ChargingVoltage() request functions and broadcasting the charging commands to the LTC4101 over the SMBus. 4. The LTC4101 will still respond to Smart Battery critical warning messages without host intervention. 16 Wake-up Charging Mode ...
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... LTC4101 will resume charging using the previous ChargingVoltage() AND ChargingCurrent() function val- ues, if the CHGEN pin is released by the external device. 9. Insufficient DCIN voltage to charge the battery. The LTC4101 will resume charging using the previous ChargingVoltage() AND ChargingCurrent() function val- ues, when there is sufficient DCIN voltage to charge the . ...
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... EXTERNAL RESISTOR R THA R THB C represents the capacitance between the SafetySignal SS and GND. C may be added to provide additional noise SS immunity from transients in the application. C exceed 1nF if the LTC4101 is to properly sense the value SafetySignal CHARGE STATUS BITS DESCRIPTION RES_UR, Underrange RES_HOT BATTERY_PRESENT RES_HOT ...
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... DD AC_PRESENT 12.5k + 33k – 25k + 25k – 14 ENCODER + 25k – + – 12.5k Circuit Concept (I LIM LIM LTC4101 Trip Points and Ranges (See Figure 5) CONTROLLED CHARGING VOLTAGE V VOLTAGE (V ) RANGE GRANULARITY LIM OUT V < 0.09V 2900mV < V VLIM VCCP OUT < 4240mV 0.17V < V 2900mV < V VDD ...
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... PROGRAMMED VALUE (V) NOTE: THE LTC4101 CAN BE PROGRAMMED WITH ChargingVoltage() FUNCTION VALUES BETWEEN 1.104V AND 2.9V, HOWEVER, THE BATTERY CHARGER CONTROLLER OUTPUT VOLTAGE MAY BE ZERO WITH PROGRAMMED VALUES BELOW 2.9V. Figure 6. Transfer Function of Charger The Current DAC Block The current DAC is a delta-sigma modulator which con- trols the effective value of an external resistor set the current limit of the charger ...
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... AC_PRESENT bit in the ChargerStatus() function is cleared. The ACP output pin is designed to drive 2mA continuously. Adapter Limiting An important feature of the LTC4101 is the ability to automatically adjust charging current to a level which avoids overloading the wall adapter. This allows the prod- uct to operate at the same time that batteries are being charged without complex load management algorithms ...
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... Consult the battery manufacturer for information on how your battery terminates charging. Setting Output Current Limit (Refer to Figure 1) The LTC4101 current DAC and the PWM analog circuitry must coordinate the setting of the charger current. Failure will result in incorrect charge currents. ...
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... N-Channel efficiency generally improves with a larger MOSFET. Using asymmetrical MOSFETs may achieve cost savings or efficiency gains. Both of the LTC4101 MOSFET drivers are optimized to take DSS advantage of MOSFETs Q TD-off delay specification of around 60ns or less. Larger ...
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... 231mW Soft-Start and Undervoltage Lockout MAX The LTC4101 is soft-started by the 0.12µF capacitor on the I pin. On start-up then ramp rate set by the internal 30µA pull-up rating D current and the external capacitor. Battery charging current starts ramping up when I and full current is achieved with I ...
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... SMBus inputs. Therefore it is good design practice to protect the SMBus inputs as shown in Figure 10 CONNECTOR TO BATTERY Figure 10. Recommended SMBus Transient Protection LTC4101 ⎛ ⎞ V BAT ⎜ ⎟ – ...
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... Interfacing with a Selector The LTC4101 is designed to be used with a true analog multiplexer for the SafetySignal sensing path. Some se- lector ICs from various manufacturers may not implement this ...
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... BSC 0° – 8° 0.65 (.0256) BSC 0.22 – 0.38 (.009 – .015) TYP LTC4101 7.90 – 8.50* (.311 – .335 7.40 – 8.20 (.291 – .323) 2.0 (.079) MAX 0.05 (.002) MIN G24 SSOP 0204 ...
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... LTC4101 U TYPICAL APPLICATIO LTC4101 Li-Ion Battery Charger 12V DCIN FROM WALL ADAPTER R11 1.21k 5.5V 10k 10k SDA D4 SCL D5 RELATED PARTS PART NUMBER DESCRIPTION LTC1760 Smart Battery System Manager LTC4006 Small, High Efficiency, Fixed Voltage, Lithium-Ion Battery Charger LTC4007 High Efficiency, Programmable Voltage ...