LTC4088 LINER [Linear Technology], LTC4088 Datasheet
LTC4088
Available stocks
Related parts for LTC4088
LTC4088 Summary of contents
Page 1
... An ideal diode ensures that system power is available from the battery when the input current limit is reached or if the USB or wall supply is removed. The LTC4088 is available in the low profi le 14-Lead 4mm × 3mm × 0.75mm DFN surface mount package. , LTC and LT are registered trademarks of Linear Technology Corporation. ...
Page 2
... CHRG 14-LEAD (4mm × 3mm) PLASTIC DFN EXPOSED PAD (PIN 15) IS GND, MUST BE SOLDERED TO PCB ORDER PART NUMBER LTC4088EDE Order Options Tape and Reel: Add #TR Lead Free: Add #PBF Lead Free Tape and Reel: Add #TRPBF Lead Free Part Marking: Consult LTC Marketing for parts specifi ed with wider operating temperature ranges. ...
Page 3
... TRKL BAT Rising Threshold Voltage Relative to V FLOAT Timer Starts when BAT FLOAT BAT < V TRKL C C 5mA CHRG BAT = 4.5V CHRG I = 200mA BAT and BAT) LTC4088 = 2.94k, unless otherwise noted. CLPROG MIN TYP MAX 4.30 4.35 3.95 4.00 200 50 3.5 BAT + 0.3 4.7 4.5 4.6 4.7 1.8 2.25 2.7 0.18 0. 4.179 4 ...
Page 4
... Maximum Rating condition for extended periods may affect device reliability and lifetime. Note 2: The LTC4088E is guaranteed to meet performance specifi cations from 0°C to 85°C. Specifi cations over the – 40°C to 85°C operating temperature range are assured by design, characterization and correlation with statistical process controls ...
Page 5
... R = 2.94k CLPROG PROG I = 0mA OUT 88 5x CHARGING EFFICIENCY 86 1x CHARGING 84 EFFICIENCY 2.7 3.0 3.6 3.9 3.3 BATTERY VOLTAGE (V) LTC4088 T = 25°C unless otherwise noted. A Output Voltage vs Output Current (Battery Charger Disabled) 4. BAT 4.25 4. 3.4V BAT 3.75 3.50 3.25 4.2 0 200 400 600 OUTPUT CURRENT (mA) 4088 G02 Battery Drain Current ...
Page 6
... LTC4088 W U TYPICAL PERFOR A CE CHARACTERISTICS Output Voltage vs Output Current in Suspend 5.0 5x MODE 4.5 4.0 3.5 1x MODE 3 BUS V = 3.3V BAT R = 2.94k CLPROG 2.5 0 0.5 1 1.5 2 2.5 OUTPUT CURRENT (mA) 4088 G10 Battery Charge Current vs Temperature 600 500 400 THERMAL REGULATION 300 200 100 0 –40 – 100 120 TEMPERATURE (° ...
Page 7
... V D2 (Pin 4): Mode Select Input Pin. D2, in combination with the D0 pin and D1 pin, controls the current limit and battery charger functions of the LTC4088 (see Table 1). This pin is pulled low by a weak current sink. C/X (Pin 5): End of Charge Indication Program Pin. This pin pin ...
Page 8
... This pin is pulled low by a weak current sink. D1 (Pin 14): Mode Select Input Pin. D1, in combination with the D0 pin and the D2 pin, controls the current limit and battery charger functions of the LTC4088 (see Table 1). This pin is pulled low by a weak current sink. Exposed Pad (Pin 15): GND. Must be soldered to the PCB to provide a low electrical and thermal impedance connection to ground ...
Page 9
... W BLOCK DIAGRA LTC4088 4088f 9 ...
Page 10
... USB power. Because power is con- served, the LTC4088 allows the load current on V exceed the current drawn by the USB port without exceed- ing the USB load specifi cations. ...
Page 11
... CLPROG I I • h VBUS BUSQ CLPROG R CLPROG where I is the quiescent current of the LTC4088, BUSQ V is the CLPROG servo voltage in current limit, CLPROG R is the value of the programming resistor and CLPROG h is the ratio of the measured current at V CLPROG the sample current delivered to CLPROG. Refer to the ...
Page 12
... However, if more conductance is needed, an external P-channel MOSFET transistor can be added from BAT The GATE pin of the LTC4088 drives the gate of the OUT P-channel MOSFET transistor for automatic ideal diode control. The source of the external P-channel MOSFET ...
Page 13
... U OPERATIO Battery Charger The LTC4088 includes a constant-current/constant-volt- age battery charger with automatic recharge, automatic termination by safety timer, low voltage trickle charging, bad cell detection and thermistor sensor input for out of temperature charge pausing. When a battery charge cycle begins, the battery charger fi ...
Page 14
... C/X pin, the ⎯ C ⎯ H ⎯ R ⎯ G pin is released (Hi-Z). The ⎯ C ⎯ H ⎯ R ⎯ G pin does not respond to the C/X threshold if the LTC4088 current limit. This prevents false end of charge indications due to insuffi cient power available to the battery charger fault occurs while charging, the pin is switched at 35kHz ...
Page 15
... The input switching regulator is enabled whenever V is above the UVLO voltage and the LTC4088 is not in one of the two USB suspend modes (500µA or 2.5mA). The ideal diode is enabled at all times and cannot be disabled ...
Page 16
... If the input current is less than 100mA, the measurement accuracy may be reduced, but it does not affect the average current loop since it will not be in regulation. The LTC4088 includes a current-reversal comparator which monitors inductor current and disables the synchronous rectifi ...
Page 17
... CDRH6D38 V and V Bypass Capacitors BUS OUT The style and value of capacitors used with the LTC4088 determine several important parameters such as regula- tor control-loop stability and input voltage ripple. Because the LTC4088 uses a step-down switching power supply from its input current waveform contains ...
Page 18
... Primary thermistor bias resistor (see Figure 2) NOM R1 = Optional temperature range adjustment resistor (see Figure The trip points for the LTC4088’s temperature qualifi ca- tion are internally programmed at 0.349 • V threshold and 0.765 • V Therefore, the hot trip point is set when: R NTCHOT R ...
Page 19
... USB Inrush Limiting The USB specifi cation allows at most 10µF of downstream capacitance to be hot-plugged into a USB hub. In most LTC4088 applications, 10µF should be enough to provide adequate fi ltering on V the following circuit can be used to soft-connect additional capacitance. ...
Page 20
... High frequency currents, such as the input current on the LTC4088, tend to fi nd their way on the ground plane along a mirror path directly beneath the incident path on the top of the board. If there are slits or cuts in the ground plane due to other traces on that layer, the current will be forced to go around the slits ...
Page 21
... U U APPLICATIO S I FOR ATIO Battery Charger Stability Considerations The LTC4088’s battery charger contains both a con- stant-voltage and a constant-current control loop. The constant-voltage loop is stable without any compensation when a battery is connected with low impedance leads. Excessive lead length, however, may add enough series inductance to require a bypass capacitor of at least 1µ ...
Page 22
... C1, C3: MURATA GRM21BR61A106KE19 C2: MURATA GRM188R71C104KA01 L1: COILCRAFT LPS4018-332MLC M1, M2: SILICONIX Si2333 R2: VISHAY-DALE NTHS0603N011-N1003F USB Compliant Switching Charger V SW BUS D0 LDO3V3 R1 D1 µC LTC4088 100k D2 CHRG NTC CLPROG PROG C/X GND R2 T 100k 8.2Ω 2.94k 499Ω 0.1µF ...
Page 23
... Plastic DFN (4mm × 3mm) (Reference LTC DWG # 05-08-1708 Rev B) 0.70 ±0.05 3.30 ±0.05 PACKAGE OUTLINE 0.25 ± 0.05 0.50 BSC 3.00 REF 4.00 ±0.10 (2 SIDES 0.05 TYP 3.00 ±0.10 (2 SIDES) 0.75 ±0.05 0.00 – 0.05 LTC4088 R = 0.115 0.40 ± 0.10 TYP 8 14 3.30 ±0.10 1.70 ± 0.10 PIN 1 NOTCH R = 0.20 OR 0.35 × 45° CHAMFER (DE14) DFN 0806 REV 0.25 ± 0.05 0.50 BSC 3.00 REF BOTTOM VIEW— ...
Page 24
... LTC4066 USB Power Controller and Battery Charger LTC4085 USB Power Manager with Ideal Diode Controller and Li-Ion Charger LTC4088-1 High Effi ciency USB Power Manager and Battery Charger with Regulated Output Voltage LTC4089/LTC4089-5 USB Power Manager with Ideal Diode Controller and High Effi ciency Li-Ion Battery Charger ThinSOT is a trademark of Linear Technology Corporation ...