MAX1870AETJ Maxim Integrated Products, MAX1870AETJ Datasheet

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... Analog Output Indicates Adapter Current ♦ Input Voltage from 8V to 28V ♦ Battery Voltage from 0 to 17.6V ♦ Charges Li+ or NiCd/NiMH Batteries ♦ Tiny 32-Pin Thin QFN (5mm x 5mm) Package PART MAX1870AETJ MAX1870AETJ+ +Denotes lead-free package. FROM WALL ADAPTER Applications Step-Up/Step-Down Features Ordering Information ...

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... ICTL = 0 ICTL = REFIN 2 _______________________________________________________________________________________ LDO Current........................................................................50mA Continuous Power Dissipation (T 32-Pin Thin QFN 5mm x 5mm (derate 21mW/°C above +70°C) ......................................1.7W Operating Temperature Range MAX1870AETJ .................................................-40°C to +85°C + 0.3V) Storage Temperature Range .............................-60°C to +150°C LDO + 0.3V) Lead Temperature (soldering, 10s) ................................ +300°C DLOV = ...

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ELECTRICAL CHARACTERISTICS (continued) (Circuit of Figure DCIN CSSP 0. VCTL = LDO, CELLS = FLOAT, GND = PGND = 0, V REFIN values are +25°C.) A PARAMETER DCIN ...

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Step-Up/Step-Down Li+ Battery Charger ELECTRICAL CHARACTERISTICS (continued) (Circuit of Figure DCIN CSSP CSSN 0. VCTL = LDO, CELLS = FLOAT, GND = PGND = 0, V REFIN values are at T ...

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ELECTRICAL CHARACTERISTICS (continued) (Circuit of Figure DCIN CSSP 0. VCTL = LDO, CELLS = FLOAT, GND = PGND = 0, V REFIN values are +25°C.) A PARAMETER V ...

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Step-Up/Step-Down Li+ Battery Charger ELECTRICAL CHARACTERISTICS (Circuit of Figure DCIN CSSP CSSN 0. VCTL = LDO, CELLS = FLOAT, GND = PGND = 0, V REFIN PARAMETER CHARGE-VOLTAGE REGULATION VCTL Range ...

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ELECTRICAL CHARACTERISTICS (continued) (Circuit of Figure DCIN CSSP 0. VCTL = LDO, CELLS = FLOAT, GND = PGND = 0, V REFIN PARAMETER SUPPLY AND LINEAR REGULATOR DCIN Input Voltage Range ...

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Step-Up/Step-Down Li+ Battery Charger ELECTRICAL CHARACTERISTICS (continued) (Circuit of Figure DCIN CSSP CSSN 0. VCTL = LDO, CELLS = FLOAT, GND = PGND = 0, V REFIN PARAMETER ERROR AMPLIFIERS GMV ...

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Figure 16V, CELLS = REFIN, V DCIN BATTERY INSERTION AND REMOVAL BATTERY REMOVAL BATTERY INSERTION CCV CCI CCI 2.00ms/div SYSTEM LOAD-TRANSIENT RESPONSE STEP-DOWN MODE 200μs CHARGE-CURRENT STEP RESPONSE STEP-DOWN 400μs _______________________________________________________________________________________ Li+ Battery Charger Typical ...

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Step-Up/Step-Down Li+ Battery Charger (Circuit of Figure 16V, CELLS = REFIN, V DCIN EFFICIENCY vs. BATTERY VOLTAGE 12V 16V ...

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Figure 16V, CELLS = REFIN, V DCIN REF LOAD REGULATION 4.11 4.10 4.09 4.08 4.07 4.06 4.05 4.04 4.03 0 500 1000 1500 2000 LOAD CURRENT (μA) LDO vs. TEMPERATURE 0.8 0.6 0.4 0.2 0 ...

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Step-Up/Step-Down Li+ Battery Charger (Circuit of Figure 16V, CELLS = REFIN, V DCIN STEP-UP SWITCHING WAVEFORM V = 12V 16V BATT 2.00μs PIN NAME Device Power Supply. Output of the 5.4V linear regulator supplied ...

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PIN NAME Charge-Current Control Input. Drive ICTL from V 12 ICTL Setting the Charge Current section. Drive ICTL to GND to disable charging. Cell-Count Selection Input. Connect CELLS to GND for two Li+ cells. Float CELLS for three Li+ cells, ...

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Step-Up/Step-Down Li+ Battery Charger OPTIONAL REVERSE- ADAPTER PROTECTION + AC D1 ADAPTER - 32 C5 1μ 1μ 10kΩ 0.01μF 0.01μF 0.01μF HOST 9 VDD 10 DIGITAL INPUT 11 ...

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OPTIONAL REVERSE- ADAPTER PROTECTION OPTIONAL + AC D1 ADAPTER - 32 C5 1μ 1μF SHORT 3 R4 OPEN OPEN SHORT 11 12 LDO R10 R12 OPEN OPEN 0.01μF ...

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Step-Up/Step-Down Li+ Battery Charger Detailed Description The MAX1870A includes all of the functions necessary to charge Li+, NiMH, and NiCd batteries. A high-effi- ciency H-bridge topology DC-DC converter controls charge voltage and current. A proprietary control scheme offers improved efficiency ...

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CSSN CSS A = 18V/V CURRENT- SENSE AMPLIFIERS (6.7A FOR 30mΩ) CSSP A = 18V/V CSSS CLS CCS CCI 50mV x ICTL REFIN CSIP A = 18V/V CSI CSIN 22.5mV (42mA ON 30mΩ) CHARGE-CURRENT BLOCK (6.7A FOR 30mΩ) 3.6V CCV ...

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Step-Up/Step-Down Li+ Battery Charger The input source current is the sum of the MAX1870A quiescent current, the charger input current, and the system load current. The MAX1870A’s 6mA maximum quiescent current is minimal compared to the charge and load currents. ...

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Continuous output current for V reduces output ripple. The MAX1870A uses the state machine shown in Figure 5. The controller switches between the states A, B, and C, depending on V and V . State D provides PFM IN ...

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Step-Up/Step-Down Li+ Battery Charger up operation. During this mode, the MAX1870A regu- lates the step-up on-time. Initially DBST switches M2 on (state C) and the inductor current ramps up with a dI/ After the inductor current ...

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STATE B STATE Figure 6. MAX1870A Step-Down Inductor Current Waveform STATE B STATE C V > 0 BATT Figure 7. Step-Up Inductor-Current Waveform signal based on the integrated error of the input cur- rent, ...

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Step-Up/Step-Down Li+ Battery Charger • CCMP: CCMP compares the current-mode control point, LVC, to the inductor current. In step-down mode, the off-time (state A) is terminated when the inductor current falls below the current threshold set by LVC. In step-up ...

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Switching Frequency The MAX1870A includes input and output-voltage feed- forward to maintain pseudo-fixed-frequency (400kHz) operation. The time in state B is set according to the input voltage, output voltage, and a time constant. In step-up/step-down mode the switching frequency is ...

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Step-Up/Step-Down Li+ Battery Charger LTF GM x PWM sC OUT Setting the LTF = 1 to solve for the unity-gain frequency yields: ⎛ ⎜ PWM MV ⎝ 2π For ...

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Since the output capacitor’s impedance has little effect on the response of the current loop, only a single pole is required to compensate this loop. A and A are the internal gains of the current- ...

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Step-Up/Step-Down Li+ Battery Charger LDO provides a 5.4V supply derived from DCIN and delivers over 10mA. The n-channel MOSFET driver DBST is powered by DLOV and can source 2.5A and sink 5A. Since LDO provides power to the internal ana- ...

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MOSFET Power Dissipation Table 5 shows the resistive losses and switching losses in each of the MOSFETs during either step-up or step- down operation. Table 5 provides a first-order estimate, but does not consider second-order effects such as ripple current ...

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Step-Up/Step-Down Li+ Battery Charger Table 5. MOSFET Resistive and Switching Losses STEP-DOWN MODE DESIGNATION ⎛ V BATT ⎜ M1 ⎝ V DCIN ⎛ − ⎜ D4 ⎝ DCIN MAX ( ...

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Layout and Bypassing Bypass DCIN with a 1µF to ground (Figure 1). Optional diodes D1 and D2 protect the MAX1870A when the DC power-source input is reversed. A signal diode for D1 is adequate because DCIN only powers the LDO ...

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Step-Up/Step-Down Li+ Battery Charger Figure 14. Recommended Layout for the MAX1870A Pin Configuration TOP VIEW MAX1870A THIN QFN 30 ______________________________________________________________________________________ BATT PGND RS1b LOAD TRANSISTOR ...

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For the latest package outline information www.maxim-ic.com/packages.) D D/2 MARKING XXXXX PIN # 1 I.D. C -DRAWING NOT TO SCALE- ______________________________________________________________________________________ Li+ Battery Charger ...

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... Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time. 32 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 © 2005 Maxim Integrated Products Package Information (continued) ...