LTC4011 Linear Technology, LTC4011 Datasheet
LTC4011
Available stocks
Related parts for LTC4011
LTC4011 Summary of contents
Page 1
... The LTC4011 automatically senses the presence adapter and battery insertion or removal. Heavily dis- charged batteries are precharged with a trickle current. The LTC4011 can simultaneously use both –∆V and ∆T/∆t fast charge termination techniques and can detect various battery faults. If necessary, a top-off charge is automati- cally applied to NiMH batteries after fast charging is completed ...
Page 2
... W U ORDER PART NUMBER LTC4011EFE MAX UNITS µ 4. –15 mV 600 mV 5.5 V – 3.475 V 3.55 V –1 mA 105 ...
Page 3
... Decreasing CELL ● CHEM = 3.3 (NiCd) ● CHEM = 0V (NiMH) ● V Increasing TEMP ● V Decreasing, Not Charging TEMP ● V Decreasing, Fast Charge TEMP ● ● ● ● 49.9k TIMER LTC4011 MIN TYP MAX UNITS 6.5 10 13.5 mV 6 ±0.3 – 150 µA – µA ...
Page 4
... Note 1: Absolute Maximum Ratings are those values beyond which the life of the device may be impaired. Note 2: The LTC4011E is guaranteed to meet performance specifications from 0°C to 70°C. Specifications over the – 40°C to 85°C operating temperature range are assured by design, characterization and correlation with statistical process controls ...
Page 5
... TEMPERATURE (°C) 4011 G04 Fast Charge Current Output Regulation 20V 50°C 0 –1 0°C –2 – BAT (V) 4011 G07 LTC4011 4011 G02 4011 G05 25° 4011 G08 ...
Page 6
... FAULT is an open-drain output to GND with an operating voltage range of GND to V CHRG (Pin 3): Active-Low Charge Indicator Output. The LTC4011 indicates it is providing charge to the battery by connecting this pin to GND. Refer to the Operation and Applications Information sections for further details. This output is capable of driving an LED and should be left floating if not used ...
Page 7
... Suggested applied voltage range is GND to 34V. READY (Pin 19): Active-Low Ready-to-Charge Output. The LTC4011 connects this pin to GND if proper operating voltages for charging are present. Refer to the Operation section for complete details on charge qualification. This output is capable of driving an LED and should be left floating if not used ...
Page 8
... LTC4011 W BLOCK DIAGRA DCIN 1 FAULT 2 CHRG 3 CHEM 4 5 GND TEMP 7 V CELL 8 V CDIV 9 TIMER DataSheet U .com SHUTDOWN THERMISTOR INTERFACE CHARGER STATE A/D CONTROL CONVERTER LOGIC BATTERY DETECTOR REGULATOR CHARGE TIMER VOLTAGE REFERENCE REGULATOR INFET 20 FET DIODE READY ...
Page 9
... FAST CHARGE** CHARGE** (1C) (C/10) NiCd OR NiMH – ∆ MAX AUTOMATIC RECHARGE *t IS PROGRAMMED MAXIMUM FAST CHARGE DURATION MAX **OPTIONAL TEMPERATURE LIMITS APPLY Figure 1. LTC4011 State Diagram LTC4011 , CC < 900mV PRECHARGE** (C/5 FOR t /12) MAX V < 900mV CELL V < 1.22V AT t */12 ...
Page 10
... LTC4011 verifies that the sensed tem- perature is between 5°C and 45°C. If these temperature limits are not met or if its own die temperature is too high, the LTC4011 will indicate a fault and not allow charging to begin greater than 2.85V, battery temperature ...
Page 11
... GND CDIV to allow detection of battery removal. Note that the LTC4011 also uses the FAULT output to indicate that charging is suspended due to invalid battery or internal die temperatures. However, the IC does not enter the fault state in these cases and normal operation 4 DataSheet U ...
Page 12
... LTC4011 U OPERATIO PWM Current Source Controller An integral part of the LTC4011 is the PWM current source controller. The charger uses a synchronous step-down architecture to produce high efficiency and limited thermal dissipation. The nominal operating frequency of 550kHz allows use of a smaller external filter components. The TGATE and BGATE outputs have internally clamped volt- age swings ...
Page 13
... The LTC4011 will properly charge over a wide range of DCIN and BAT voltage combinations. Operating the LTC4011 in low dropout or with DCIN much greater than BAT will force the PWM frequency to be much less than 550kHz. The LTC4011 disables charging and sets a fault if a large DCIN to BAT differential would cause generation of audible noise ...
Page 14
... PC: Precharge FC: Fast Charge (Initial –∆V Termination Hold Off of t TOC: Top-Off Charge (Only for NiMH ∆T/∆t FC Termination After Initial t AR: Automatic Recharge (Temperature Limits Apply to State Termination Only) Table 3. LTC4011 Time Limit Programming Examples TYPICAL FAST R CHARGE RATE TIMER 24 ...
Page 15
... For thermistors with a room temperature value of 10k or less, replace R3 with a short. The LTC4011 is designed to work best with a 1% 10k NTC thermistor with a β of 3750. In this case, the values for the external network are given by ...
Page 16
... LTC4011 to accurately terminate fast charge under a variety of applied charge rates. Use of a synchronous PWM topology improves efficiency and lowers power dissipation. A full-featured 2A LTC4011 application is shown in Fig- ure 8. FET-based PowerPath allows for maximum input voltage range from the DC adapter. The inherent voltage ratings of the V ...
Page 17
... BGATE READY PGND LTC4011 SENSE TIMER BAT 49.9k R2 GND 10k CHEM V CDIV CELL INTV V DD TEMP 0.1µF 4011 F06 Figure 6. Minimum LTC4011 Application R5 10k 3k 3k INFET FAULT TGATE CHRG TOC READY BGATE LTC4011 PGND SENSE DCIN TIMER BAT 49.9k R2 GND 10k ...
Page 18
... The application includes all average cell voltage and battery temperature sensing circuitry required for the LTC4011 to utilize its full range of charge qualification, safety monitoring and fast charge termina- tion features. A green LED indicates valid DC input voltage and installed battery, while a pair of red LEDs indicates charging ...
Page 19
... Because NiMH charging terminated due to ∆T/∆t and the fast charge cycle had lasted more than t rises above 4.25V CC the LTC4011 begins a top-off charge with a current of I PROG minutes with the CHRG and TOC outputs continuously asserted. ...
Page 20
... NiCd cells. A second possibility is to configure an LTC4011-based charger to accept battery packs with varying numbers of cells. By including R2 of the average cell voltage divider ...
Page 21
... LTC4011 are short. These feedback traces need to be run together as a single pair with the smallest spacing possible on any given layer on which they are routed. Locate any filter component on these traces next to the LTC4011, and not at the L1 V BAT sense resistor location ...
Page 22
... Route analog ground as a trace tied back to the LTC4011 GND pin before connecting to any other ground. Avoid using the system ground plane. A useful CAD technique is to make analog ground a separate ground net and use a 0Ω ...
Page 23
... SHALL NOT EXCEED 0.150mm (.006") PER SIDE 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 represen- tation that the interconnection of its circuits as described herein will not infringe on existing patent rights. LTC4011 6.40 – 6.60* (.252 – .260) 3.86 ( ...
Page 24
... LTC4011 RELATED PARTS PART NUMBER DESCRIPTION LTC1325 Microprocessor-Controlled Battery Management System ® LT 1510 Constant-Voltage/Constant-Current Battery Charger LT1511 3A Constant-Voltage/Constant-Current Battery Charger LT1513 SEPIC Constant- or Programmable-Current/Constant- Voltage Battery Charger LTC1760 Smart Battery System Manager LTC1960 Dual Battery Charger/Selector with SPI LTC4008 High Efficiency, Programmable Voltage/Current Battery ...