LTC4006 Linear Technology, LTC4006 Datasheet
LTC4006
Available stocks
Related parts for LTC4006
LTC4006 Summary of contents
Page 1
... The PWM controller is a synchronous, quasi-constant fre- quency, constant off-time architecture that will not gener- ate audible noise even when using ceramic capacitors. The LTC4006 is available in 8.4V, 12.6V and 16.8V versions with 0.8% accuracy. Charging current is programmable with a single sense resistor to 4% typical accuracy. Charg- ...
Page 2
... 20V DCIN CONDITIONS Sum of Current from CLP, CLN, DCIN (Note 2) LTC4006-6 LTC4006-6 LTC4006-2 LTC4006-2 LTC4006-4 LTC4006-4 V – V Target = 100mV CSP BAT V = 11.5V (LTC4006-2) BAT V = 7.6V (LTC4006-6) BAT V = 12V (LTC4006-4) BAT V < 6V, V – V Target = 10mV BAT CSP BAT BAT ...
Page 3
... INFET – – INFET INFET V Rising NTC V Falling NTC V 10V NTC Voltage Falling at PROG LTC4006-6 LTC4006-2 LTC4006-4 LTC4006-6 LTC4006-2 LTC4006 100 – LTC4006 = 12V unless otherwise noted. BAT MIN TYP MAX 140 165 200 – ...
Page 4
... TGATE DCIN = 0V, CLN = 12V BGATE Note 4: The LTC4006E is guaranteed to meet performance specifications from Specifications over the – operating temperature range are assured by design, characterization and correlation with statistical process controls. ACP/SHDN (Pin 3): Open-Drain Output Used to Indicate if the AC Adapter Voltage is Adequate for Charging ...
Page 5
... PGND (Pin 14): High Current Ground Return for the BGATE < BAT Driver. BGATE (Pin 15): Drives the bottom external N-channel MOSFET of the battery charger buck converter. INFET (Pin 16): Drives the Gate of the External Input PFET. 11. REF EA – 3k – BAT 10 LT1055 LTC4006 LTC4006 – 0.6V 4006 TC sn4006 4006is 5 ...
Page 6
... Q2 15 PGND OPERATIO Overview The LTC4006 is a synchronous current mode PWM step- down (buck) switcher battery charger controller. The charge current is programmed by the sense resistor (R between the CSP and BAT pins. The final float voltage is internally programmed to 8.4V (LTC4006-6), 12.6V 6 CLN TIMER/CONTROLLER ...
Page 7
... ACP/SHDN pin is driven low and the charger is disabled. Battery Charger Controller The LTC4006 charger controller uses a constant off-time, current mode step-down architecture. During normal op- eration, the top MOSFET is turned on each cycle when the oscillator sets the SR latch and turned off when the main ...
Page 8
... LTC4006 U OPERATIO Table 1. Truth Table for LTC4006 Operation MODE Shut Down by Low Adapter Voltage Conditioning a Depleted Battery Normal Charging Input Current Limited Charging Charger Paused Due to Thermistor Out of Range Shut Down by ACP/SHDN Pin Terminated by Low-Battery Fault (Note 1) Top-Off Charging. C/10 is Latched Timer is Reset by C/10 Comparator (Latched), ...
Page 9
... If the voltage at NTC is outside of the resistor divider limits, then the DFF will set T will be shut down, and the timer will be suspended until T returns to zero (see Figure 4). , keeps switch S1 BAD T CLK (NOT TO SCALE) VOLTAGE ACROSS THERMISTOR V NTC LTC4006 LTC4006 R9 – 32.4k NTC 6 ~4. 0.47 F 60k + – 45k – ...
Page 10
... 4006 F05 Figure TIMER RT 3. 200k LTC4006 P 33k CHG OUT IN 4006 F06 Figure 6. Microprocessor Interface LTC4006 ADAPTER DCIN POWER 470k ACP/SHDN Figure 7 LTC4006 ADAPTER DCIN POWER ACP/SHDN SWITCH OPEN WHEN Figure 8 4006 F07 4006 F08 sn4006 4006is ...
Page 11
... U U APPLICATIO S I FOR ATIO Soft-Start The LTC4006 is soft started by the 0.12 F capacitor on the I pin. On start-up, I pin voltage will rise quickly to 0.5V then ramp rate set by the internal 40 A pull-up current and the external capacitor. Battery charging current starts ramping up when I ...
Page 12
... The diode may be omitted if the efficiency loss can be tolerated. IN – OUT IN Calculating IC Power Dissipation The power dissipation of the LTC4006 is dependent upon the gate charge of the top and bottom MOSFETs (Q T)R Q respectively) The gate charge is determined from the DS(ON manufacturer’s data sheet and is dependent upon both the OSC ...
Page 13
... OSC 292mW Adapter Limiting An important feature of the LTC4006 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. ...
Page 14
... Avoid running the connection using multiple layers in parallel. Minimize capacitance from this node to any other trace or plane. 4. Place the output current sense resistor right next to the inductor output but oriented such that the IC’s LTC4006 R9 NTC C7 R9A R 4006 F11 Figure 11 ...
Page 15
... LTC DWG # 05-08-1641 .004 – .0098 (0.102 – 0.249) .229 – .244 .0250 (5.817 – 6.198) (0.635) BSC LTC4006 to CSP and BAT. See SENSE DIRECTION OF CHARGING CURRENT R SNS 4006 F13 BAT CSP .189 – .196* (4.801 – 4.978) ...
Page 16
... Battery Charger trademark of Linear Technology Corporation. SENSE Linear Technology Corporation 16 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 2A Li-Ion Battery Charger Q3 INPUT SWITCH C1 0.1 F DCIN INFET LTC4006 CHG CLP ACP/SHDN CLN I TGATE MON NTC BGATE R PGND T I CSP ...