Datasheet LTC4120, LTC4120-4.2 (Analog Devices) - 7

LTC4120/LTC4120-4.2
TYPICAL PERFORMANCE CHARACTERISTICS TA = 25°C, unless otherwise noted. Switching Frequency BAT Pin Leakage Current/VBAT-VIN vs Temperature Buck Efficiency vs Battery Current vs Temperature
95 16 400 1.4 VIN = OPEN-CIRCUIT 90 14 VBAT = 4.2V 350 1.2 FREQ = INTVCC FREQ = INTVCC 85 12 300 1.0 80 VBAT 10 250 0.8 75 -V (MHz) (µA) IN 8 200 V (mV) f OSC 0.6 FREQ = GND 70 IN = 12.5V I BAT FREQ = GND V EFFICIENCY (%) IN = 14V 6 150 65 VIN = 20V 2 UNITS TESTED 0.4 VIN = 30V 4 I 100 60 BAT L IBAT 0.2 SW = 68µH, SLF12555T-680M1R3 55 FREQ = GND 2 V 50 BAT-VIN 2 UNITS TESTED VBAT = 4.2V VBAT-VIN 0 50 0 0 –50 –25 0 25 50 75 100 125 0 50 100 150 200 250 300 350 400 –50 –25 0 25 50 75 100 125 TEMPERATURE (°C) IBAT (mA) TEMPERATURE (°C) 4120 G07 4120 G08 4120 G09
Wireless Power Transfer Efficiency, Typical tMIN(ON) vs Temperature VIN_RX vs Battery Current
130 70 24 2 UNITS TESTED VFLOAT = 8.3V 125 L 60 SW = SLF6028-470MR59 22 R 120 PROG = 4.64k 115 50 20 V 9mm EFFICIENCY 110 IN_RX 10mm EFFICIENCY (ns) 40 18 11mm EFFICIENCY 105 (V) 9mm V_RX 30 16 10mm V_RX t MIN(0N) 100 EFFICIENCY (%) 11mm V_RX 95 20 14 90 10 12 85 80 0 10 –50 –22 0 25 50 75 100 125 0 50 100 150 200 250 TEMPERATURE (°C) IBAT (mA) 4120 G10 4120 G11
Typical Burst Mode Waveforms, Typical Wireless Charging Cycle Burst Mode Trigger Current IBAT = 38mA
450 4.5 V 90 BAT 400 4.0 80 RPROG = 3k 350 3.5 V 70 SW V 5V/DIV CHRG V 300 3.0 BAT 60 IBAT , V RPROG = 6.2k 0V 250 2.5 CHRG 50 (mA) VPROG 200 2.0 500mV/DIV (V) 40 0V I BAT ILSW 150 BAT = 940mAhr 1.5 30 200mA/DIV L 0mA BATTERY CURRENT (mA) SW = TDK SLF4075 15µH 100 RFB1 = 732k, RFB2 = 976k 1.0 20 RPROG = 3.01k 4µs/DIV 4120 G14 50 APPLICATION CCT OF FIGURE 10 0.5 10 SPACING = 14mm 0 0 0 0 1 2 3 10 15 20 25 30 35 40 TIME (HOURS) VIN (V) 4120 G12 4120 G13 Rev. G For more information www.analog.com 7 Document Outline Features Applications Typical Application Description Absolute Maximum Ratings Pin Configuration Order Information Electrical Characteristics Typical Performance Characteristics Pin Functions Block Diagram Test Circuit Operation Applications Information Package Description Revision History Typical Application Related Parts