MAX17085BETL+T Maxim Integrated Products, MAX17085BETL+T Datasheet
MAX17085BETL+T
Specifications of MAX17085BETL+T
Related parts for MAX17085BETL+T
MAX17085BETL+T Summary of contents
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... PDAs and Mobile Communicators 5V and 3.3V Supplies 2-to-4, Li+-Cell, Battery-Powered Devices Ordering Information PART TEMP RANGE MAX17085BETL+ -40°C to +85°C +Denotes a lead(Pb)-free/RoHS-compliant package. *EP = Exposed pad. Pin Configuration appears at end of data sheet. Quick-PWM is a trademark of Maxim Integrated Products, Inc. Features PIN-PACKAGE 40 TQFN-EP* ...
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Integrated Charger, Dual Main Step-Down Controllers, and Dual LDO Regulators ABSOLUTE MAXIMUM RATINGS (Note 1) TON, DCIN, CSSP, BATT, CSIP to GND, LX_ to GND ........................................................-0.3V to +28V CSIP to CSIN, CSSP to CSSN ..............................-0.3V to +0.3V LDO3, LDO5, VCC ...
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Integrated Charger, Dual Main Step-Down Controllers, and Dual LDO Regulators ELECTRICAL CHARACTERISTICS (continued) (Circuit of Figure 1, no load on LDO5, LDO3, OUT5, OUT3, and REF 19V 5V BSTC LXC BATT ...
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Integrated Charger, Dual Main Step-Down Controllers, and Dual LDO Regulators ELECTRICAL CHARACTERISTICS (continued) (Circuit of Figure 1, no load on LDO5, LDO3, OUT5, OUT3, and REF 19V 5V BSTC LXC BATT ...
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Integrated Charger, Dual Main Step-Down Controllers, and Dual LDO Regulators ELECTRICAL CHARACTERISTICS (continued) (Circuit of Figure 1, no load on LDO5, LDO3, OUT5, OUT3, and REF 19V 5V BSTC LXC BATT ...
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Integrated Charger, Dual Main Step-Down Controllers, and Dual LDO Regulators ELECTRICAL CHARACTERISTICS (continued) (Circuit of Figure 1, no load on LDO5, LDO3, OUT5, OUT3, and REF 19V 5V BSTC LXC BATT ...
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Integrated Charger, Dual Main Step-Down Controllers, and Dual LDO Regulators ELECTRICAL CHARACTERISTICS (continued) (Circuit of Figure 1, no load on LDO5, LDO3, OUT5, OUT3, and REF 19V 5V BSTC LXC BATT ...
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Integrated Charger, Dual Main Step-Down Controllers, and Dual LDO Regulators ELECTRICAL CHARACTERISTICS (Circuit of Figure 1, no load on LDO5, LDO3, OUT5, OUT3, and REF 19V 5V BSTC LXC BATT otherwise ...
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Integrated Charger, Dual Main Step-Down Controllers, and Dual LDO Regulators ELECTRICAL CHARACTERISTICS (continued) (Circuit of Figure 1, no load on LDO5, LDO3, OUT5, OUT3, and REF 19V 5V BSTC LXC BATT ...
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Integrated Charger, Dual Main Step-Down Controllers, and Dual LDO Regulators ELECTRICAL CHARACTERISTICS (continued) (Circuit of Figure 1, no load on LDO5, LDO3, OUT5, OUT3, and REF 19V 5V BSTC LXC BATT ...
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Integrated Charger, Dual Main Step-Down Controllers, and Dual LDO Regulators ELECTRICAL CHARACTERISTICS (continued) (Circuit of Figure 1, no load on LDO5, LDO3, OUT5, OUT3, and REF 19V 5V BSTC LXC BATT ...
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Integrated Charger, Dual Main Step-Down Controllers, and Dual LDO Regulators (Circuit of Figure 20V, V ADP SYS IINP ERROR vs. SYSTEM CURRENT (DC SWEEP 19V ADAPTER - ADAPTER ABSENT, V ...
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Integrated Charger, Dual Main Step-Down Controllers, and Dual LDO Regulators (Circuit of Figure 20V, V ADP SYS BATTERY REMOVAL (V = 11V) BATT MAX17085B toc10 1.5V 11V 19V 0A 3-CELL BATTERY 100µs/div POWER-SOURCE SELECTOR SCHEME ...
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Integrated Charger, Dual Main Step-Down Controllers, and Dual LDO Regulators (Circuit of Figure 20V, V ADP SYS LDO3 LOAD REGULATION 3.40 3.35 3.30 3.25 3. 19V ADAPTER 3.15 CHARGER OFF SMPS5 AND SMPS3 ...
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Integrated Charger, Dual Main Step-Down Controllers, and Dual LDO Regulators (Circuit of Figure 20V, V ADP SYS SMPS3 EFFICIENCY vs. LOAD CURRENT (CHARGER AND SMPS5 ARE OFF) 100 20V 80 12V 75 ...
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Integrated Charger, Dual Main Step-Down Controllers, and Dual LDO Regulators PIN NAME Inductor Connection for SMPS3. Connect LX3 to the switched side of the inductor. LX3 is the lower 1 LX3 supply rail for the DH3 high-side gate driver. Boost ...
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Integrated Charger, Dual Main Step-Down Controllers, and Dual LDO Regulators PIN NAME AC-Detect Output. This open-drain output is low impedance when ACIN is greater than 1.5V, with a 18 ACOK delay of 44ms. The ACOK output remains high impedance when ...
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Integrated Charger, Dual Main Step-Down Controllers, and Dual LDO Regulators PIN NAME Pulse-Skipping Control Input. This tri-level input determines the operating mode for the switching regulators. 36 SKIP High (V CC Mid (1.8V) = forced-PWM operation GND = ultrasonic mode ...
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Integrated Charger, Dual Main Step-Down Controllers, and Dual LDO Regulators V AC ADAPTER ADP N3 R4 150kI N4 C DCIN 1FF R ACIN1 N4 PROVIDES REVERSE ADAPTER PROTECTION. REPLACE WITH DIODE IF REVERSE ADAPTER PROTECTION IS NOT NEEDED. R ACIN2 ...
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Integrated Charger, Dual Main Step-Down Controllers, and Dual LDO Regulators Table 2. Component Suppliers SUPPLIER AVX Corp. www.avxcorp.com Central www.centralsemi.com Semiconductor Corp. Fairchild www.fairchildsemi.com Semiconductor International Rectifier www.irf.com KEMET Corp. www.kemet.com NEC/TOKIN America www.nec-tokinamerica.com Panasonic Corp. www.panasonic.com/industrial Philips/nxp www.semiconductors.philips.com Semiconductor ...
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Integrated Charger, Dual Main Step-Down Controllers, and Dual LDO Regulators Thermal-Fault Protection (t The MAX17085B features a thermal fault-protection cir- cuit. When the junction temperature rises above +160NC, a thermal sensor activates the fault latch, pulls PGOOD low, enables the ...
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Integrated Charger, Dual Main Step-Down Controllers, and Dual LDO Regulators Charger Detailed Description The MAX17085B charger has three regulations loops: a voltage-regulation loop (CCV) and two current-regulation loops (CCI and CCS). The loops operate independently of each other. The CCV ...
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Integrated Charger, Dual Main Step-Down Controllers, and Dual LDO Regulators If there are two clock edges on ISET within 20ms, the PWM filter is enabled and ISET accepts digital PWM input. The PWM filter accepts the digital signal with a ...
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Integrated Charger, Dual Main Step-Down Controllers, and Dual LDO Regulators Table 4. Charger Operating Mode Truth Table ADAPTER INPUT DCIN PRESENT CURRENT (NOTE CSSP CSSN < UVLO Yes > OCP ...
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Integrated Charger, Dual Main Step-Down Controllers, and Dual LDO Regulators cycle cannot start until the IMAX comparator’s output goes low. U The ZCMP comparator provides zero-crossing detec- tion during discontinuous conduction. ZCMP com- pares the current-sense feedback signal to 10mV. ...
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Integrated Charger, Dual Main Step-Down Controllers, and Dual LDO Regulators Continuous Conduction Mode With sufficiently large charge current, the MAX17085B's inductor current never crosses zero, which is defined as continuous conduction mode. The controller starts a new cycle by turning ...
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Integrated Charger, Dual Main Step-Down Controllers, and Dual LDO Regulators ON5 OUT5 SYSTEM ON3 OUT3 SYSTEM SW(NOM) TON TON where C = 6pF. ...
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Integrated Charger, Dual Main Step-Down Controllers, and Dual LDO Regulators Valley Current-Limit Protection The current-limit circuit employs a unique “valley” cur- rent-sensing algorithm that senses the inductor current through the low-side MOSFET, across LX to AGND. If the current through ...
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Integrated Charger, Dual Main Step-Down Controllers, and Dual LDO Regulators Table 5. Main SMPS Fault Protection and Shutdown Operation MODE Shutdown (ON_ = High Internal error amplifier target immediately resets to GND. to Low) Output UVP (Latched Internal error amplifier ...
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Integrated Charger, Dual Main Step-Down Controllers, and Dual LDO Regulators I RIPPLE C = OUT(CHG) f × × BATT where k is the derating factor for the capacitor CAP-BIAS due to DC voltage bias; k CAP-BIAS ...
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Integrated Charger, Dual Main Step-Down Controllers, and Dual LDO Regulators Output Capacitor ESR The output filter capacitor must have low enough equivalent series resistance (ESR) to meet output ripple and load- transient requirements, yet have high enough ESR to satisfy ...
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Integrated Charger, Dual Main Step-Down Controllers, and Dual LDO Regulators 100 400kHz 200kHz 600kHz 800kHz 10 1 0.5 0.6 0.7 0.8 DUTY CYCLE Figure 6. Scale Factor vs. Duty Cycle where function of maximum duty cycle (lowest ...
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Integrated Charger, Dual Main Step-Down Controllers, and Dual LDO Regulators × (HS) QRR The total high-side MOSFET power dissipation is: PD (HS) PD ≈ (HS TOTAL COND The optimum high-side MOSFET trades the ...
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Integrated Charger, Dual Main Step-Down Controllers, and Dual LDO Regulators The boost capacitors (C ) selected must be large BST enough to handle the gate charging requirements of the high-side MOSFETs. Select the boost capacitors to avoid discharging the capacitor ...
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Integrated Charger, Dual Main Step-Down Controllers, and Dual LDO Regulators A reasonable minimum value for h is 1.5 for most normal regulators. With the extended on-time feature, the mini- mum h value of 1 can be used. Adjusting this up ...
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Integrated Charger, Dual Main Step-Down Controllers, and Dual LDO Regulators U Minimize the main SMPS current-sensing errors by connecting LX3 and LX5 directly to the drain of the low-side MOSFET. Minimize the charger current- sense resistor trace lengths, and ensure ...
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Integrated Charger, Dual Main Step-Down Controllers, and Dual LDO Regulators Pin Configuration TOP VIEW ISET 32 REF 33 GND ILIM3 34 35 ILIM5 MAX17085B 36 SKIP TON 37 38 ON3 ...
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