MAX782CBX Maxim Integrated Products, MAX782CBX Datasheet
MAX782CBX
Specifications of MAX782CBX
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MAX782CBX Summary of contents
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... Standby (linear regulators alive) 5.5V to 30V Input Range Small SSOP Package Fixed Output Voltages Available: 3.3 (standard) 3.45 (High-Speed Pentium™) 3.6 (PowerPC™) ______________Ordering Information PART MAX782CBX MAX782RCBX MAX782SCBX Ordering Information continued on last page. __________________Pin Configuration TOP VIEW VPPA VPPB +3.3V ...
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... VPPA, VPPB Current .........................................................100mA Continuous Power Dissipation (T SSOP (derate 11.76mW/°C above +70°C) ...................941mW Operating Temperature Ranges: MAX782CBX/MAX782__CBX ...............................0°C to +70°C MAX782EBX/MAX782__EBX ............................-40°C to +85°C Storage Temperature Range .............................-65°C to +160°C Lead Temperature (soldering, 10sec) .............................+300°C = 0mA, ON3 = ON5 = 5V, other digital input levels are 0V or +5V, T ...
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Controller for Notebook Computers ELECTRICAL CHARACTERISTICS (continued) (V+ = 15V, GND = PGND = 0V REF unless otherwise noted.) PARAMETER INTERNAL REGULATOR AND REFERENCE VL Output Voltage ON5 = ON3 = 0V, 5.5V < V+ < ...
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Triple-Output Power-Supply Controller for Notebook Computers __________________________________________Typical Operating Characteristics (Circuit of Figure 1, Transpower transformer type TTI5870, T EFFICIENCY vs. +5V OUTPUT CURRENT, 200kHz 100 10V 15V IN 80 COMPONENTS, ...
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Controller for Notebook Computers _____________________________Typical Operating Characteristics (continued) (Circuit of Figure 1, Transpower transformer type TTI5870, T PULSE-WIDTH MODULATION MODE WAVEFORMS HORIZONTAL = 500ns/div +5V OUTPUT CURRENT = 1A INPUT VOLTAGE = 16V +5V LOAD-TRANSIENT RESPONSE HORIZONTAL = 200 s/div ...
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Triple-Output Power-Supply Controller for Notebook Computers _____________________________Typical Operating Characteristics (continued) (Circuit of Figure 1, Transpower transformer type TTI5870, VDD ≥ 13V, T +5V LINE-TRANSIENT RESPONSE, RISING HORIZONTAL = 20 s/div LOAD +3.3V LINE-TRANSIENT RESPONSE, RISING HORIZONTAL = ...
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Controller for Notebook Computers ______________________________________________________________Pin Description PIN NAME 1 ON3 Logic input to turn on +3.3V. Logic high turns on the regulator. Connect to VL for automatic start-up. #1 level-translator/comparator noninverting input. Inverting comparator input is internally connected to 2 ...
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Triple-Output Power-Supply Controller for Notebook Computers _________________________________________________Pin Description (continued) PIN NAME 24 BST5 +5V-supply boost capacitor connection (0.1µF to LX5) 25 DL5 +5V-supply external MOSFET synchronous-rectifier drive output 26 PGND Power ground 27 FB5 +5V-supply feedback input and low-side current-sense ...
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Controller for Notebook Computers BATTERY INPUT C1 5.5V TO 30V 33 F (NOTE 1) VPP CONTROL INPUTS 0 25m 10 H +3. 1N5819 N3 C14 C7 150 F 150 F (NOTE 2) 0.01 ...
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Triple-Output Power-Supply Controller for Notebook Computers +5V LDO V+ LINEAR REGULATOR 5V VL 3.3V +3.3V REF REFERENCE GND 4V 2.8V 300kHz/200kHz SYNC OSCILLATOR VPPA LINEAR DA0 REGULATOR DA1 VPPB LINEAR DB0 REGULATOR DB1 D3 1.65V D2 1.65V D1 1.65V VH ...
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Controller for Notebook Computers 60kHz MAIN PWM REF, 3.3V COMPARATOR (OR INTERNAL 5V REFERENCE) SLOPE COMP MINIMUM CURRENT (IDLE-MODE) 25mV 4 A SS_ 3.3V ON_ N N –100mV VDD REG SINGLE-SHOT (SEE FIG. 2) Figure 3. PWM ...
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Triple-Output Power-Supply Controller for Notebook Computers +3.3V and +5V PWM Buck Controllers The two current-mode PWM controllers are identical except for different preset output voltages and the addition of a flyback winding control loop to the +5V side (see Figure ...
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Controller for Notebook Computers Boost Gate-Driver Supply Gate-drive voltage for the high-side N-channel switch is generated with a flying-capacitor boost circuit as shown in Figure 4. The capacitor is alternately charged from the VL supply via the diode and placed ...
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Triple-Output Power-Supply Controller for Notebook Computers High-Side Supply (VDD) The 15V VDD supply is obtained from the rectified and filtered secondary of transformer L2. VDD is enabled whenever the +5V supply is on (ON5 = high). The pri- mary and ...
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Controller for Notebook Computers The comparators are always active when V+ is above +4V, even when VH is 0V. Thus, Q1-Q3 will sink current to GND even when VH is 0V, but they will only source current from VH when ...
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Triple-Output Power-Supply Controller for Notebook Computers +5V Transformer (T1) Table 3 lists two commercially available transformers and parts for a custom transformer. The following instructions show how to determine the transformer parameters required for a custom design the ...
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Controller for Notebook Computers FAT, HIGH-CURRENT TRACES MAIN CURRENT PATH KELVIN SENSE TRACES MAX782 Figure 5. Kelvin Connections for the Current-Sense Resistors MOSFETs with low gate-threshold voltage specifica- tions (i.e., maximum rather than 3V) are GS(TH) preferred, ...
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Triple-Output Power-Supply Controller for Notebook Computers Because this ramp is applied to the current-limit circuit, the actual time for the output voltage to ramp up depends on the load current and output capacitor value. Using Figure 1’s circuit with a ...
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Controller for Notebook Computers Table 4. Surface-Mount Components Factory FAX Company [country code] Central Semi [ 1] (516) 435-1824 Coiltronics [ 1] (407) 241-9339 IRC [ 1] (213) 772-9028 Murata-Erie [ 1] 404 736-3030 Nihon [81] 3-3494-7414 Siliconix [ 1] ...
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Triple-Output Power-Supply Controller for Notebook Computers where C is the reverse transfer capacitance of the RSS high-side MOSFET (a data sheet parameter the switching frequency, and I is the peak current DRIVE available from the MAX782’s large high-side ...
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Controller for Notebook Computers 5. Keep the gate connections to the MOSFETs short for low inductance (less than 20mm long and more than 0.5mm wide) to ensure clean switching achieve good shielding best to keep all ...
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Triple-Output Power-Supply Controller for Notebook Computers +5V SUPPLY C4 +3.3V SUPPLY 100nF VCC SET1 HYST1 C2 100 ICL7665 1.3V R5 820k OUT2 SET2 R2 390k GND Figure 8. Power-Up Sequencing for ...
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Controller for Notebook Computers Table 5. Components for Low-Voltage Operation (Circuit of Figure 200kHz, V Range = 5.5V to 12V) IN Coiltronics CTX03-12062 Transformer L2: (low-leakage inductance, 10µH primary) Filter Capacitor C6: 660µF Sense Resistor: 25mΩ 1N5819 ...
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Triple-Output Power-Supply Controller for Notebook Computers Total Shutdown Circuits When the +5V and +3.3V supplies are off, the complete MAX782 circuit consumes only about 70µA, plus any leakage through the off MOSFETs. Some NiCd batter- ies can be damaged if ...
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Controller for Notebook Computers ________Evaluation Kit Information The MAX782 evaluation kit (EV kit assembled, surface-mount demonstration board. The kit embodies the standard application circuit and uses dip switches to control the 3V, 5V, and VPP outputs. The board ...
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Triple-Output Power-Supply Controller for Notebook Computers Figure 14. MAX782 EV Kit Schematic 26 ______________________________________________________________________________________ ...
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Controller for Notebook Computers Figure 15. MAX782 EV Kit Top Component Layout and Silk Screen, Top View ______________________________________________________________________________________ Triple-Output Power-Supply 27 ...
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Triple-Output Power-Supply Controller for Notebook Computers Figure 16. MAX782 EV Kit Ground Plane (Layers 2 and 3), Top View 28 ______________________________________________________________________________________ ...
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Controller for Notebook Computers Figure 17. MAX782 EV Kit Top Layer (Layer 1), Top View ______________________________________________________________________________________ Triple-Output Power-Supply 29 ...
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Triple-Output Power-Supply Controller for Notebook Computers Figure 18. MAX782 EV Kit, Bottom Component Layout and Silk Screen, Bottom View 30 ______________________________________________________________________________________ ...
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Controller for Notebook Computers Figure 19. MAX782 EV Kit Bottom Layer (Layer 4), Top View ______________________________________________________________________________________ Triple-Output Power-Supply 31 ...
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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. 32 __________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 (408) 737-7600 © 1994 Maxim Integrated Products ...