MAX1844ETP+ Maxim Integrated Products, MAX1844ETP+ Datasheet
MAX1844ETP+
Specifications of MAX1844ETP+
Related parts for MAX1844ETP+
MAX1844ETP+ Summary of contents
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... CPU Core Supplies Chipset/RAM Supplies as Low as 1V 1.8V and 2.5V Supplies *Contact factory for availability. Quick-PWM is a trademark of Maxim Integrated Products. Pin Configuration appears at end of data sheet. ________________________________________________________________ Maxim Integrated Products For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at 1-888-629-4642, or visit Maxim’ ...
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High-Speed Step-Down Controller with Accurate Current Limit for Notebook Computers ABSOLUTE MAXIMUM RATINGS V+ to GND ..............................................................-0.3V to +28V GND .....................................................-0. OUT, PGOOD, SHDN to GND ..................................-0.3V to +6V FB, ILIM, LATCH, ...
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High-Speed Step-Down Controller with Accurate Current Limit for Notebook Computers ELECTRICAL CHARACTERISTICS (continued) (Circuit of Figure 15V +25°C.) A PARAMETER REF Sink Current REF in regulation REF Fault Lockout Voltage Falling ...
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High-Speed Step-Down Controller with Accurate Current Limit for Notebook Computers ELECTRICAL CHARACTERISTICS (continued) (Circuit of Figure 15V +25°C.) A PARAMETER DH Gate-Driver On-Resistance BST - LX forced to 5V (Note 4) ...
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High-Speed Step-Down Controller with Accurate Current Limit for Notebook Computers ELECTRICAL CHARACTERISTICS (continued) (Circuit of Figure 15V PARAMETER Minimum Off-Time (Note 2) Quiescent Supply Current ( forced above the regulation ...
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High-Speed Step-Down Controller with Accurate Current Limit for Notebook Computers __________________________________________Typical Operating Characteristics = 15V, SKIP = GND, TON = unconnected, T (Circuit of Figure EFFICIENCY vs. LOAD CURRENT 100 ...
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High-Speed Step-Down Controller with Accurate Current Limit for Notebook Computers = 15V, SKIP = GND, TON = unconnected, T (Circuit of Figure NO-LOAD SUPPLY CURRENT vs. INPUT VOLTAGE (PWM MODE ...
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High-Speed Step-Down Controller with Accurate Current Limit for Notebook Computers PIN NAME QSOP QFN Current-Sense Input. Connect a low-value current-sense resistor between CS and GND for accurate current sensing. For lower power dissipation (less accurate) current sensing, connect CS to ...
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High-Speed Step-Down Controller with Accurate Current Limit for Notebook Computers PIN NAME QSOP QFN Analog Supply Input. Connect to the system supply voltage, 4.5V to 5.5V, with a series 20Ω resistor Bypass to GND with a ...
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High-Speed Step-Down Controller with Accurate Current Limit for Notebook Computers 20V 5V BIAS SUPPLY ON/OFF CONTROL LOW-NOISE CONTROL 270kΩ 130kΩ SEE TABLE 1 FOR OTHER COMPONENT SELECTIONS. Figure 1. Standard Application Circuit Detailed Description The MAX1844 ...
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High-Speed Step-Down Controller with Accurate Current Limit for Notebook Computers 28V TON ON-TIME COMPUTE TON TON TRIG 1-SHOT SKIP SHDN OVP 1.14V 0. LATCH POR 20ms TIMER 0.1V 0. ...
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High-Speed Step-Down Controller with Accurate Current Limit for Notebook Computers Table 3. Operating Mode Truth Table SHDN SKIP DL MODE High Shutdown Low Run (PWM Switching CC Low Noise Run 1 GND Switching (PFM/PWM) 1 ...
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High-Speed Step-Down Controller with Accurate Current Limit for Notebook Computers ∆ BATT OUT = ∆ ON-TIME TIME Figure 3. Pulse-Skipping/Discontinuous Crossover Point where V is the sum of the parasitic voltage drops DROP1 in the inductor ...
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High-Speed Step-Down Controller with Accurate Current Limit for Notebook Computers Current-Limit Circuit (ILIM) The current-limit circuit employs a unique “valley” cur- rent-sensing algorithm (Figure 4). If the magnitude of the current-sense voltage above the current-limit threshold, the ...
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High-Speed Step-Down Controller with Accurate Current Limit for Notebook Computers TO ERROR AMP FIXED 1.8V FIXED 2.5V Figure 6. Feedback Mux Power-Good Output (PGOOD) The PGOOD window comparator continuously monitors the output. PGOOD is actively held low in shutdown, standby, ...
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... The minimum practical inductor value is one that causes the circuit to operate at the edge of critical conduction (where the inductor current just touches zero with every cycle at maximum load). Inductor val- Dual Mode is a trademark of Maxim Integrated Products. 16 ______________________________________________________________________________________ ues lower than this grant no further size-reduction benefit. The MAX1844’ ...
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High-Speed Step-Down Controller with Accurate Current Limit for Notebook Computers The amount of output sag is also a function of the maxi- mum duty factor, which can be calculated from the on- time and minimum off-time: ∆ LOAD(MAX) ...
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High-Speed Step-Down Controller with Accurate Current Limit for Notebook Computers Output Capacitor Stability Considerations Stability is determined by the value of the ESR zero rela- tive to the switching frequency. The point of instability is given by the following equation: ...
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High-Speed Step-Down Controller with Accurate Current Limit for Notebook Computers pation limits often limits how small the MOSFET can be. Again, the optimum occurs when the switching (AC) losses equal the conduction (R DS(ON) switching losses do not usually become ...
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High-Speed Step-Down Controller with Accurate Current Limit for Notebook Computers BOTTOM SIDE AGND PLANE V CC REF BYPASS BYPASS V DD BYPASS PGND PLANE VIA TO POWER GROUND USE AGND PLANE TO: - BYPASS V AND REF CC - TERMINATE ...
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High-Speed Step-Down Controller with Accurate Current Limit for Notebook Computers Therefore, V must be greater than 3.13V, even with IN very large output capacitance, and a practical input volt- age with reasonable output capacitance would be 3.48V. PC Board Layout ...
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High-Speed Step-Down Controller with Accurate Current Limit for Notebook Computers (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information www.maxim-ic.com/packages.) 22 ______________________________________________________________________________________ Package Information ...
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High-Speed Step-Down Controller with Accurate Current Limit for Notebook Computers (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information www.maxim-ic.com/packages.) ______________________________________________________________________________________ Package Information (continued) 23 ...
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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. 24 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 © 2002 Maxim Integrated Products ...