PDF《19-4245; Rev 0; 1/12》

90 95

100 mA USB 500mA mode

450 475

500 Input limit programmed to 1.5A, IFCHG = 1500mA

1350 1500

1650 Adaptive Input-Current Limit (AICL) (Note 4) DC voltage where charge current is regulated 4.5 V DC voltage where charge current is set to 75mA 4.4 Input Limit Switch VDC = 5.5V, IBYP = 100mA

35 80 mI BUCK OPERATION Switching Frequency VBAT = 3.6V

4 MHz Maximum Duty Cycle 99.5 % Minimum On-Time

55 ns Maximum On-Time

10 ?s Minimum Off-Time

65 ns Soft-Start Time 1.5 ms High-Side Resistance ILX = 100mA, VDC = 5.5V

120 250 mI Low-Side Resistance ILX = 100mA, VDC = 5.5V

150 220 mI Thermal Regulation Temperature (TREG) I2C programmable 2-bits (90, 105, 120, and disable selections,

105 default)

105 °C Thermal Regulation Gain Percentage decrease in IFCHG above the thermal regulation temperature

5 %/°C BATTERY CHARGER PRECHARGE Battery-Prequalification Lower Threshold (VPQLTH) VBAT rising, 130mV hysteresis 2.1 V Dead-Battery Charge Current (IDBAT) 0V ≤ VBAT ≤ 2.1V

45 mA Battery-Prequalification Upper Threshold (VPQUTH)** VBAT rising, 150mV hysteresis 2.5 V Prequalification Charge Current (IPQ) Percentage of fast-charge current programmed

10 % CONSTANT-CURRENT MODE BAT Fast-Charge Current Range (IFC)

5 bitsC50mA steps, RCS = 47mI

250 1550 mA Fast-Charge Current Accuracy TA = +15NC to +45NC -5 +5 % JEITA safety region (Figure 6) -65 -50 -35 % Maxim Integrated Products??6 MAX8971 尺寸最小的1.55A 单节Li+电池DC-DC充电器 ELECTRICAL CHARACTERISTICS (continued) (VDC = 5V, CBYP = 1FF, IFCHG = 500mA, CAVL = 4.7FF, VTHM = AVL/2, TA = -40NC to +85NC, unless otherwise noted. Typical values are at TA = +25NC.) (Note 2) PARAMETER CONDITIONS MIN TYP MAX UNITS CONSTANT VOLTAGE MODE Battery Regulation Voltage (VBATREG) IBAT = 100mA, operating in voltage-regulation mode, I2 C- programmable 4.1V, 4.15V, 4.2V, and 4.35V selection TA = +25NC -0.5 +0.5 % TA = -40NC to +85NC -1 +1 JEITA safety region, percentage of battery regulation voltage (Note 6)

96 97

98 Battery Refresh Threshold (Below regulation point), 100mV and 150mV selection, default 150mV (N........