MAX1902EAI+ Maxim Integrated Products, MAX1902EAI+ Datasheet
MAX1902EAI+
Specifications of MAX1902EAI+
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MAX1902EAI+ 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, Low-Noise Power-Supply Controllers for Notebook Computers 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 +6V ...
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Multi-Output, Low-Noise Power-Supply Controllers for Notebook Computers ELECTRICAL CHARACTERISTICS (continued) (V+ = 15V, both PWMs on, SYNC = V L values are +25°C.) A PARAMETER Maximum Duty Factor SYNC Input High-Pulse Width SYNC Input Low-Pulse Width ...
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Multi-Output, Low-Noise Power-Supply Controllers for Notebook Computers ELECTRICAL CHARACTERISTICS (continued) (V+ = 15V, both PWMs on, SYNC = values are +25°C.) A PARAMETER FAULT DETECTION (MAX1901/MAX1902) Overvoltage Trip Threshold Overvoltage Fault Propagation ...
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Multi-Output, Low-Noise Power-Supply Controllers for Notebook Computers 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 Fixed ...
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Multi-Output, Low-Noise Power-Supply Controllers for Notebook Computers ELECTRICAL CHARACTERISTICS (continued) (V+ = 15V, both PWMs on, SYNC = PARAMETER V+ Standby Supply Current V+ Standby Supply Current in Dropout V+ Shutdown Supply Current Quiescent ...
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Multi-Output, Low-Noise Power-Supply Controllers for Notebook Computers (Circuit of Figure 1, Table 1, 6A/500kHz components, T EFFICIENCY vs. 5V OUTPUT CURRENT 100 15V ON5 = 5V 60 ...
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Multi-Output, Low-Noise Power-Supply Controllers for Notebook Computers (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) 5V LOAD TRANSIENT RESPONSE 10V ...
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Multi-Output, Low-Noise Power-Supply Controllers for Notebook Computers PIN NAME SSOP QFN 1 29 CSH3 2 30 CSL3 3 31 FB3 12OUT (MAX1902 STEER (MAX1901/ MAX1904 (MAX1902 SECFB (MAX1901/ MAX1904 SYNC 7 ...
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Multi-Output, Low-Noise Power-Supply Controllers for Notebook Computers PIN NAME QSOP QFN 15 13 SEQ 16 14 DH5 17 15 LX5 18 17 BST5 19 18 DL5 20 19 PGND SHDN 23 22 ...
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Multi-Output, Low-Noise Power-Supply Controllers for Notebook Computers INPUT 7V TO 24V 0.1µ OUTPUT ON/OFF 3.3V ON/OFF Figure 1. Standard 3.3V/5V Application Circuit (MAX1901/MAX1904) ______________________________________________________________________________________ ON/OFF 10Ω 0.1µF V+ SHDN ...
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Multi-Output, Low-Noise Power-Supply Controllers for Notebook Computers Standard Application Circuit The basic MAX1901/MAX1904 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 components from Table ...
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Multi-Output, Low-Noise Power-Supply Controllers for Notebook Computers Table 2. Component Suppliers MANUFACTURER USA PHONE Dale-Vishay 402-564-3131 Fairchild 408-721-2181 Semiconductor International 310-322-3331 Rectifier Sanyo 619-661-6835 Sumida 847-956-0666 Taiyo Yuden 408-573-4150 The MAX1901/MAX1902/MAX1904 contain ten major circuit blocks (Figure 2). The ...
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Multi-Output, Low-Noise Power-Supply Controllers for Notebook Computers INPUT 7V to 24V 5V ALWAYS REF BST3 DH3 LX3 3.3V DL3 CSH3 CSL3 R1 FB3 R2 + 0.6V TIME/ON5 Figure 2. MAX1902 Functional Diagram 14 ______________________________________________________________________________________ SHDN V+ ...
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Multi-Output, Low-Noise Power-Supply Controllers for Notebook Computers REF SLOPE COMP 30mV SKIP DAC COUNTER SHDN SOFT-START -100mV REF SECFB Figure 3. PWM Controller Functional Block Diagram ______________________________________________________________________________________ MAIN PWM COMPARATOR CURRENT LIMIT CK SYNCHRONOUS RECTIFIER CONTROL ...
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Multi-Output, Low-Noise Power-Supply Controllers for Notebook Computers 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 output ...
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Multi-Output, Low-Noise Power-Supply Controllers for Notebook Computers 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 minimum. REF can supply up to ...
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Multi-Output, Low-Noise Power-Supply Controllers for Notebook Computers RESET Power-Good Voltage Monitor The power-good monitor generates a system RESET signal. At first power-up, RESET is held low until both the 3.3V and 5V SMPS outputs are in regulation. At this ...
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Multi-Output, Low-Noise Power-Supply Controllers for Notebook Computers Interference due to switching noise is reduced in PWM mode by ensuring a constant switching frequency, thus concentrating the emissions at a known frequency out- side the system audio or IF bands. ...
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Multi-Output, Low-Noise Power-Supply Controllers for Notebook Computers tor (primary) current, pulling current from the output fil- ter capacitor and causing the flyback transformer to operate in forward mode. The low impedance present the transformer secondary in forward ...
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Multi-Output, Low-Noise Power-Supply Controllers for Notebook Computers connected but no battery is installed. V exceed 30V. Minimum Input (Battery) Voltage taken at full load under the lowest battery condi- tions less than 4.2V, use ...
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Multi-Output, Low-Noise Power-Supply Controllers for Notebook Computers OUT IN OUT = × RMS LOAD V IN Therefore, when OUT I LOAD = I RMS 2 ...
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Multi-Output, Low-Noise Power-Supply Controllers for Notebook Computers P = The sum of the output power from all outputs TOTAL The equivalent output cur- TOTAL TOTAL OUT rent referred to V OUT V ( ...
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Multi-Output, Low-Noise Power-Supply Controllers for Notebook Computers Use a Schottky diode with a DC current rating equal to one third of the load current. The Schottky diode’s rated reverse breakdown voltage must be at least equal to the maximum ...
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Multi-Output, Low-Noise Power-Supply Controllers for Notebook Computers 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 V ...
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Multi-Output, Low-Noise Power-Supply Controllers for Notebook Computers Lossless-Inductor Current-Sensing The DC resistance (DCR) of the inductor can be used to sense inductor current to improve the efficiency and to reduce the cost by eliminating the sense resistor. Figure 7 ...
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Multi-Output, Low-Noise Power-Supply Controllers for Notebook Computers performance. In most applications, the circuit will be located on a multilayer board, and full use of the four or more copper layers is recommended. Use the top layer for high-current connections, ...
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Multi-Output, Low-Noise Power-Supply Controllers for Notebook Computers INPUT 6.5V TO 28V C3 ON/OFF L1 3.3V OUTPUT (3A 0.1µF 1N5819 3V ON/OFF 5V ON/OFF *V DIODES AND OUTPUT SCHOTTKY DIODES REQUIRED L FOR THE MAX1902 ONLY (SEE ...
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Multi-Output, Low-Noise Power-Supply Controllers for Notebook Computers INPUT 6V TO 24V C3 0.1µ OUTPUT * C1 1N5819 OPEN 0Ω ON/OFF ON/OFF *V DIODES AND OUTPUT SCHOTTKY DIODES REQUIRED L FOR THE MAX1901 ONLY (SEE THE OUTPUT ...
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Multi-Output, Low-Noise Power-Supply Controllers for Notebook Computers DEVICE AUXILLARY OUTPUT MAX1901 None (SECFB input) MAX1902 12V Linear Regulator MAX1904 None (SECFB input) CSH3 1 CSL3 2 FB3 3 12OUT MAX1902 SYNC 6 TIME/ON5 7 GND ...
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Multi-Output, Low-Noise Power-Supply Controllers for Notebook Computers (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information go to www.maxim-ic.com/packages.) ______________________________________________________________________________________ Package Information 31 ...
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Multi-Output, Low-Noise Power-Supply Controllers for Notebook Computers (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information go to www.maxim-ic.com/packages.) 32 ______________________________________________________________________________________ Package Information (continued) ...
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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. Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 ____________________ 33 © 2003 Maxim Integrated Products ...