MAX8741EAI+T Maxim Integrated, MAX8741EAI+T Datasheet
MAX8741EAI+T
Specifications of MAX8741EAI+T
Related parts for MAX8741EAI+T
MAX8741EAI+T Summary of contents
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... Notebook and Subnotebook Computers PDAs and Mobile Communicators Desktop CPU Local DC-DC Converters Idle Mode is a trademark of Maxim Integrated Products, Inc. Dual Mode is a trademark of Maxim Integrated Products, Inc. Pin Configurations appear 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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Multi-Output Power-Supply Controllers with High Impedance in Shutdown ABSOLUTE MAXIMUM RATINGS V+ to GND ..............................................................-0.3V to +36V PGND to GND.....................................................................±0. GND ................................................................-0.3V to +6V L BST3, BST5 to GND ..............................................-0.3V to +36V CSH3, CSH5 to GND................................................-0.3V to ...
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Multi-Output Power-Supply Controllers with High Impedance in Shutdown ELECTRICAL CHARACTERISTICS (continued) (V+ = 15V, both PWMs on, SYNC = V values are +25°C.) A PARAMETER Maximum Duty Factor SYNC Input High Pulse Width SYNC Input Low ...
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Multi-Output Power-Supply Controllers with High Impedance in Shutdown ELECTRICAL CHARACTERISTICS (continued) (V+ = 15V, both PWMs on, SYNC = values are +25°C.) A PARAMETER FAULT DETECTION Overvoltage Trip Threshold Overvoltage Fault Propagation ...
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Multi-Output Power-Supply Controllers with High Impedance in Shutdown ELECTRICAL CHARACTERISTICS (V+ = 15V, both PWMs on, SYNC = PARAMETER MAIN SMPS CONTROLLERS Input Voltage Range 3V Output Voltage in Adjustable Mode 3V Output Voltage in ...
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Multi-Output Power-Supply Controllers with High Impedance in Shutdown ELECTRICAL CHARACTERISTICS (continued) (V+ = 15V, both PWMs on, SYNC = PARAMETER V+ Standby Supply Current V+ Standby Supply Current in Dropout V+ Shutdown Supply Current ...
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Multi-Output Power-Supply Controllers with High Impedance in Shutdown (Circuit of Figure 1, Table 1, 6A/500kHz components, T EFFICIENCY vs. 5V OUTPUT CURRENT 100 15V ON5 = 5V ...
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Multi-Output Power-Supply Controllers with High Impedance in Shutdown (Circuit of Figure 1, Table 1, 6A/500kHz components, T REF OUTPUT VOLTAGE vs. OUTPUT CURRENT 2.505 2.500 2.495 2.490 2.485 OUTPUT CURRENT (mA) 3.3V LOAD-TRANSIENT RESPONSE 10V ...
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Multi-Output Power-Supply Controllers with High Impedance in Shutdown PIN NAME SSOP TQFN 1 29 CSH3 2 30 CSL3 3 31 FB3 12OUT (MAX8742 STEER (MAX8741 (MAX8742 SECFB (MAX8741 SYNC 7 4 ...
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Multi-Output Power-Supply Controllers with High Impedance in Shutdown PIN NAME SSOP TQFN 15 13 SEQ 16 14 DH5 17 15 LX5 18 17 BST5 19 18 DL5 20 19 PGND SHDN 23 ...
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Multi-Output Power-Supply Controllers with High Impedance in Shutdown INPUT 7V TO 24V 0.1μ OUTPUT ON/OFF 3.3V ON/OFF Figure 1. Standard 3.3V/5V Application Circuit (MAX8741) ______________________________________________________________________________________ ON/OFF 10Ω 0.1μF V+ SHDN ...
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Multi-Output Power-Supply Controllers with High Impedance in Shutdown Standard Application Circuit The basic MAX8741 dual-output 3.3V/5V buck converter (Figure 1) is easily adapted to meet a wide range of applications with inputs up to 28V by substituting com- ponents ...
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Multi-Output Power-Supply Controllers with High Impedance in Shutdown Table 2. Component Suppliers MANUFACTURER Dale-Vishay www.vishay.com Fairchild Semiconductor www.fairchildsemi.com International Rectifier www.irf.com Sanyo www.sanyo.com Sumida www.sumida.com Taiyo Yuden www.t-yuden.com The MAX8741/MAX8742 contain 10 major circuit blocks (Figure 2). The two ...
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Multi-Output Power-Supply Controllers with High Impedance in Shutdown INPUT 7V TO 24V V 5V ALWAYS ON L REF BST3 DH3 LX3 3.3V DL3 CSH3 CSL3 R1 FB3 R2 + 0.6V TIME/ON5 Figure 2. MAX8742 Functional Diagram 14 ______________________________________________________________________________________ SHDN ...
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Multi-Output Power-Supply Controllers with High Impedance in Shutdown REF SLOPE COMP 30mV SKIP DAC COUNTER SHDN SOFT-START -100mV REF SECFB Figure 3. PWM Controller Functional Diagram ______________________________________________________________________________________ MAIN PWM COMPARATOR CURRENT LIMIT CK SYNCHRONOUS- RECTIFIER CONTROL ...
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Multi-Output Power-Supply Controllers with High Impedance in Shutdown Table 3. SKIP PWM Table SKIP LOAD CURRENT Low Light Low Heavy High Light High Heavy FB_ I1 REF CSH_ CSL_ SLOPE COMPENSATION Figure 4. Main PWM Comparator Block Diagram The ...
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Multi-Output Power-Supply Controllers with High Impedance in Shutdown The 2.5V reference (REF) is accurate to ±2% over tem- perature, making REF useful as a precision system ref- erence. Bypass REF to GND with 1µF (min). REF can supply up ...
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Multi-Output Power-Supply Controllers with High Impedance in Shutdown DL_ is kept low whenever the corresponding SMPS is disabled, and in shutdown. Since the outputs are not actively discharged by the SMPS controller, the negative output voltage caused by quickly ...
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Multi-Output Power-Supply Controllers with High Impedance in Shutdown current to reverse at light loads. This results in fixed-fre- quency operation and continuous inductor-current flow. This eliminates discontinuous-mode inductor ringing and improves cross-regulation of transformer-coupled multiple-output supplies, particularly in circuits ...
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Multi-Output Power-Supply Controllers with High Impedance in Shutdown voltage. A linear postregulator may still be needed to meet strict output-accuracy specifications. The MAX8742 has a V pin that regulates at a fixed DD 13.5V, set by an internal resistor-divider. ...
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Multi-Output Power-Supply Controllers with High Impedance in Shutdown The exact inductor value is not critical and can be freely adjusted to make trade-offs between size, cost, and efficiency. Lower inductor values minimize size and cost but reduce efficiency due ...
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Multi-Output Power-Supply Controllers with High Impedance in Shutdown Bypass the V+ input with a 4.7µF tantalum capacitor paralleled with a 0.1µF ceramic capacitor, close to the IC. A 10Ω series resistor also recommended. IN Bypass the ...
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Multi-Output Power-Supply Controllers with High Impedance in Shutdown where the minimum required rectified secondary out- SEC put voltage V = the forward drop across the secondary FWD rectifier V = the minimum value of the main output ...
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Multi-Output Power-Supply Controllers with High Impedance in Shutdown Rectifier Diode (Transformer Secondary Diode) The secondary diode in coupled-inductor applications must withstand flyback voltages greater than 60V, which usually rules out most Schottky rectifiers. Common silicon rectifiers, such as the ...
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Multi-Output Power-Supply Controllers with High Impedance in Shutdown Table 5. Low-Voltage Troubleshooting Chart SYMPTOM CONDITION Sag or droop in V Low V OUT IN under step-load change differential, <1.5V Dropout voltage is too Low V IN high (V follows ...
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Multi-Output Power-Supply Controllers with High Impedance in Shutdown scale down the voltage. Use the maximum inductance and minimum DCR to get the maximum possible induc- tor time constant. Select R and C S mum sense-network time constant is equal ...
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Multi-Output Power-Supply Controllers with High Impedance in Shutdown d) LX node (MOSFETs, rectifier cathode, induc tor): 15mm max length Ideally, surface-mount power components are butted up to one another with their ground terminals almost touch- ing. These high-current grounds ...
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Multi-Output Power-Supply Controllers with High Impedance in Shutdown INPUT 6.5V TO 28V C3 ON/OFF L1 3.3V OUTPUT (3A 0.1μF 1N5819 3V ON/OFF 5V ON/OFF Figure 10. Triple-Output Application for the MAX8742 28 ______________________________________________________________________________________ TO 3.3V OUTPUT TO ...
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Multi-Output Power-Supply Controllers with High Impedance in Shutdown INPUT 6V TO 24V C3 0.1μ OUTPUT C1 1N5819 OPEN 0Ω ON/OFF ON/OFF Figure 11. Dual 6A Notebook Computer Power Supply ______________________________________________________________________________________ ON/OFF 10Ω 0.1μF V+ SHDN SECFB ...
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Multi-Output Power-Supply Controllers with High Impedance in Shutdown DEVICE AUXILIARY OUTPUT MAX8741 None (SECFB input) MAX8742 12V linear regulator CSH3 1 CSL3 2 FB3 3 12OUT MAX8742 SYNC 6 TIME/ON5 7 8 GND REF 9 ...
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Multi-Output Power-Supply Controllers with High Impedance in Shutdown Ordering Information (continued) PART TEMP RANGE MAX8742EAI -40°C to +85°C MAX8742EAI+ -40°C to +85°C MAX8742ETJ -40°C to +85°C MAX8742ETJ+ -40°C to +85°C +Denotes lead-free package. ______________________________________________________________________________________ PIN-PACKAGE 28 SSOP 28 SSOP ...
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Multi-Output Power-Supply Controllers with High Impedance in Shutdown (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 NOTES: 1. ...
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Multi-Output Power-Supply Controllers with High Impedance in Shutdown (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.) D D/2 MARKING XXXXX PIN # 1 I.D. ...
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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. 34 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 © 2005 Maxim Integrated Products Package Information (continued) ...