MAX1637EEE Maxim Integrated Products, MAX1637EEE Datasheet
MAX1637EEE
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MAX1637EEE Summary of contents
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... Internal Digital Soft-Start ♦ 1.1V ±2% Reference Output ♦ 1μA Total Shutdown Current ♦ Output Overvoltage Crowbar Protection ♦ Output Undervoltage Shutdown (foldback) ♦ Tiny 16-Pin QSOP Package ______________Ordering Information PART MAX1637EEE MAX1637EEE+ +Denotes lead-free package. __________Typical Operating Circuit SHDN 16 SKIP ...
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Miniature, Low-Voltage, Precision Step-Down Controller ABSOLUTE MAXIMUM RATINGS GND to PGND .............................................................+2V to -2V LX, BST to GND......................................................-0.3V to +36V BST LX...........................................................-0.3V to +6V , CSL, CSH, SHDN to GND.......................-0. ...
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ELECTRICAL CHARACTERISTICS (continued) (Circuit of Figure 5V, SYNC = +25°C.) A PARAMETER OVERVOLTAGE PROTECTION Overvoltage Trip Threshold Overvoltage Fault Propagation Delay Output Undervoltage Lockout Threshold Output Undervoltage Lockout Delay INPUTS ...
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Miniature, Low-Voltage, Precision Step-Down Controller ELECTRICAL CHARACTERISTICS (continued) (Circuit of Figure 5V, SYNC = PARAMETER OVERVOLTAGE PROTECTION Overvoltage Trip Threshold Output Undervoltage Lockout Threshold INPUTS AND OUTPUTS Logic Input Voltage High Logic ...
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Operating Characteristics (continued 3.3V +25°C, unless otherwise noted.) OUT A LOAD REGULATION vs. LOAD CURRENT -10 0.01 0.1 1 LOAD CURRENT (A) LOAD-TRANSIENT RESPONSE (3.3V/3A, ...
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Miniature, Low-Voltage, Precision Step-Down Controller ____________________________________Typical Operating Characteristics (continued 3.3V +25°C, unless otherwise noted.) OUT A TIME EXITING SHUTDOWN (V = 3.3V 7A) OUT LOAD MAX1637-16 500μs/div ______________________________________________________________Pin Description PIN NAME 1 CSH High-Side ...
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V BIAS +5V NOMINAL 0.1μF 1M ON/OFF 0.01μF Figure 1. Standard Application Circuit ______Standard Application Circuit The basic MAX1637 buck converter (Figure 1) is easily adapted to meet a wide range of applications where lower supply is ...
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Miniature, Low-Voltage, Precision Step-Down Controller Table 1. Component Selection for Standard Applications COMPONENT 2A Input Voltage Range 7V to 22V Output Voltage Range 2.5V Application Chipset Supply Frequency 300kHz Q1 High-Side 1/2 Si4902DY or 1/2 MMDF3NO3HD MOSFET 1/2 Si4902DY or ...
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TO 5.5V V BIAS V CC POWER REF 1.1V REF. SHDN SHUTDOWN CONTROL OFF UNDER- VOLTAGE FAULT OVERVOLTAGE - FAULT V -30% - REF V +7% REF Figure 2. Functional Diagram The pulse-width-modulation (PWM) controller consists of a multi-input ...
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Miniature, Low-Voltage, Precision Step-Down Controller SLOPE COMPENSATION 30mV SKIP DAC SHDN COUNTER SOFT-START -100mV Figure 3. PWM Controller Functional Diagram PWM Controller Block The heart of the current-mode PWM controller is a multi-input, open-loop comparator that sums four sig- nals: ...
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When SKIP is low, idle-mode circuitry automatically optimizes efficiency throughout the load-current range. Idle mode dramatically improves light-load efficiency by reducing the effective frequency, subsequently reducing switching losses. It forces the peak inductor current to ramp to 30% of the ...
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Miniature, Low-Voltage, Precision Step-Down Controller REF and V CC The 1.100V reference (REF) is accurate to ±2% over temperature, making REF useful as a precision system reference. Bypass REF to GND with a 0.22µF (min) capacitor. REF can ...
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For prototyping or for very high-current applications, it may be useful to wire the current-sense inputs with a twisted pair rather than PC traces (two pieces of wrapped wire twisted together are sufficient). This reduces the noise picked up at ...
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Miniature, Low-Voltage, Precision Step-Down Controller make prototype troubleshooting difficult since only 20ms or 30ms elapse before the SMPS is latched off. The overvoltage crowbar protection is disabled in out- put undervoltage mode. Output Overvoltage Protection The overvoltage crowbar-protection circuit is ...
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The exact inductor value is not critical and can be freely adjusted to allow trade-offs among size, cost, and efficiency. Lower inductor values minimize size and cost, but reduce efficiency due to higher peak- current levels. The smallest inductor value ...
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Miniature, Low-Voltage, Precision Step-Down Controller Use only specialized low-ESR capacitors intended for switching-regulator applications, such as AVX TPS, Sprague 595D, Sanyo OS-CON, or Nichicon PL series. To ensure stability, the capacitor must meet both mini- mum capacitance and maximum ESR ...
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Rectifier Clamp Diode The rectifier is a clamp across the low-side MOSFET that catches the negative inductor swing during the 60ns dead time between turning one MOSFET off and turning each low-side MOSFET on. The latest genera- tions of MOSFETs ...
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Miniature, Low-Voltage, Precision Step-Down Controller x ƒ P(gate where Q is the sum of the gate-charge values for low- g side and high-side switches. For matched MOSFETs twice the data-sheet value of ...
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V CC SYNC SKIP MAX1637 SHDN ON/OFF REF 1μF GND CC Figure 7. 3.15V to 5.5V Single-Supply Application Circuit sensing at the supply’s output terminals without interfer- ence from IR drops and ground noise. Other high-cur- rent paths ...
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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. 20 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 © 2005 Maxim Integrated Products Printed USA ...