MAX8734AEEI Maxim Integrated Products, MAX8734AEEI Datasheet
MAX8734AEEI
Specifications of MAX8734AEEI
Available stocks
Related parts for MAX8734AEEI
MAX8734AEEI Summary of contents
Page 1
... PDAs and Mobile Communication Devices 3- and 4-Cell Li+ Battery-Powered Devices Quick-PWM and Dual Mode are trademarks of Maxim Integrated Products, Inc. ________________________________________________________________ Maxim Integrated Products For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at 1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com. ♦ No Current-Sense Resistor Needed (MAX8734A) ♦ ...
Page 2
High-Efficiency, Quad-Output, Main Power- Supply Controllers for Notebook Computers ABSOLUTE MAXIMUM RATINGS V+, SHDN to GND ..................................................-0.3V to +25V BST_ to GND ..........................................................-0.3V to +30V LX_ to BST_ ..............................................................-6V to +0.3V CS_ to GND (MAX8732A/MAX8733A only) .................-2V to +6V V ...
Page 3
High-Efficiency, Quad-Output, Main Power- Supply Controllers for Notebook Computers ELECTRICAL CHARACTERISTICS (continued) (Circuit of Figure 1 and Figure 2, no load on LDO5, LDO3, OUT3, OUT5, and REF 12V, ON3 = ON5 = 0°C to ...
Page 4
High-Efficiency, Quad-Output, Main Power- Supply Controllers for Notebook Computers ELECTRICAL CHARACTERISTICS (continued) (Circuit of Figure 1 and Figure 2, no load on LDO5, LDO3, OUT3, OUT5, and REF 12V, ON3 = ON5 = 0°C to ...
Page 5
High-Efficiency, Quad-Output, Main Power- Supply Controllers for Notebook Computers ELECTRICAL CHARACTERISTICS (continued) (Circuit of Figure 1 and Figure 2, no load on LDO5, LDO3, OUT3, OUT5, and REF 12V, ON3 = ON5 = 0°C to ...
Page 6
High-Efficiency, Quad-Output, Main Power- Supply Controllers for Notebook Computers ELECTRICAL CHARACTERISTICS (continued) (Circuit of Figure 1 and Figure 2, no load on LDO5, LDO3, OUT3, OUT5, and REF 12.0.V, ON3 = ON5 = -40°C to ...
Page 7
High-Efficiency, Quad-Output, Main Power- Supply Controllers for Notebook Computers ELECTRICAL CHARACTERISTICS (continued) (Circuit of Figure 1 and Figure 2, no load on LDO5, LDO3, OUT3, OUT5, and REF 12.0.V, ON3 = ON5 = -40°C to ...
Page 8
... MAX8732A 182 180 178 176 MAX8733A 174 172 170 INPUT VOLTAGE (V) Idle Mode is a trademark of Maxim Integrated Products, Inc. 8 _______________________________________________________________________________________ Typical Operating Characteristics MAX8732A 5V OUTPUT EFFICIENCY vs. LOAD CURRENT 100 PFM MODE PWM MODE 60 50 ULTRASONIC MODE 12V ...
Page 9
High-Efficiency, Quad-Output, Main Power- Supply Controllers for Notebook Computers (Circuit of Figure 1 and Figure 2, no load on LDO5, LDO3, OUT3, OUT5, and REF 12V, ON3 = ON5 = 7mΩ 0.5V, ...
Page 10
High-Efficiency, Quad-Output, Main Power- Supply Controllers for Notebook Computers (Circuit of Figure 1 and Figure 2, no load on LDO5, LDO3, OUT3, OUT5, and REF 12V, ON3 = ON5 = 7mΩ 0.5V, ...
Page 11
High-Efficiency, Quad-Output, Main Power- Supply Controllers for Notebook Computers (Circuit of Figure 1 and Figure 2, no load on LDO5, LDO3, OUT3, OUT5, and REF 12V, ON3 = ON5 = 7mΩ 0.5V, ...
Page 12
High-Efficiency, Quad-Output, Main Power- Supply Controllers for Notebook Computers PIN NAME MAX8732A MAX8734A MAX8733A 3.3V SMPS Current-Sense Input. Connect CS3 to a current-sensing resistor from the source 1 — CS3 of the synchronous rectifier to GND. The voltage at ILIM3 ...
Page 13
High-Efficiency, Quad-Output, Main Power- Supply Controllers for Notebook Computers PIN NAME MAX8732A MAX8734A MAX8733A 5V SMPS Current-Sense Input. Connect CS5 to a current-sensing resistor from the source of 13 — CS5 the synchronous rectifier to GND. The voltage at ILIM5 ...
Page 14
High-Efficiency, Quad-Output, Main Power- Supply Controllers for Notebook Computers Typical Application Circuits The typical application circuits (Figures 1 and 2) gener- ate the 5V/5A and 3.3V/5A main supplies in a notebook computer. The input supply range 24V. ...
Page 15
High-Efficiency, Quad-Output, Main Power- Supply Controllers for Notebook Computers 24V IN 10µF 1 FDS6612A EP10QY03 N2 IRF7811AV ON OFF V CC REF *OPTIONAL CAPACITANCE BETWEEN LX AND PGND (CLOSE TO THE ...
Page 16
High-Efficiency, Quad-Output, Main Power- Supply Controllers for Notebook Computers MAX8733A is optimized for “thin and light” applications with a 5V/400kHz SMPS and a 3.3V/500kHz SMPS. The MAX8734A provides a pin-selectable switching frequency, allowing either 200kHz/300kHz or 400kHz/500kHz operation of the ...
Page 17
High-Efficiency, Quad-Output, Main Power- Supply Controllers for Notebook Computers Each PWM controller consists of a Dual-Mode feedback network and multiplexer, a multi-input PWM comparator, high-side and low-side gate drivers, and logic. The MAX8732A/MAX8733A/MAX8734A contain fault-protection circuits that monitor the main ...
Page 18
High-Efficiency, Quad-Output, Main Power- Supply Controllers for Notebook Computers These internal blocks are not powered directly from the battery. Instead, the 5V (LDO5) linear regulator steps down the battery voltage to supply both internal circuit- ry and the gate drivers. ...
Page 19
High-Efficiency, Quad-Output, Main Power- Supply Controllers for Notebook Computers tinuous and discontinuous inductor-current operation (also known as the critical conduction point): × OUT LOAD SKIP ( ) × where K ...
Page 20
High-Efficiency, Quad-Output, Main Power- Supply Controllers for Notebook Computers Reference and Linear Regulators (REF, LDO5, and LDO3) The 2V reference (REF) is accurate to ±1% over tem- perature, making REF useful as a precision system reference. Bypass REF to GND ...
Page 21
High-Efficiency, Quad-Output, Main Power- Supply Controllers for Notebook Computers undervoltage-protection circuit, this current-limit method is effective in almost every circumstance. A negative current limit prevents excessive reverse inductor currents when V sinks current. The nega- OUT tive current-limit threshold is ...
Page 22
High-Efficiency, Quad-Output, Main Power- Supply Controllers for Notebook Computers high-side MOSFETs at the expense of efficiency, without degrading the turn-off time (Figure 10). Adaptive dead-time circuits monitor the DL_ and DH_ drivers and prevent either FET from turning on until ...
Page 23
High-Efficiency, Quad-Output, Main Power- Supply Controllers for Notebook Computers Table 3. Operating-Mode Truth Table MODE CONDITION Power-Up LDO5 < UVLO threshold SHDN = high, ON3 or ON5 Run enabled Overvoltage Either output > 111% of nominal level, PRO = low ...
Page 24
High-Efficiency, Quad-Output, Main Power- Supply Controllers for Notebook Computers Power-Up Sequencing and On/Off Controls (ON3, ON5) ON3 and ON5 control SMPS power-up sequencing. ON3 or ON5 rising above 2.4V enables the respective outputs. ON3 or ON5 falling below 1.6V disables ...
Page 25
High-Efficiency, Quad-Output, Main Power- Supply Controllers for Notebook Computers at maximum load).Inductor values lower than this grant no further size-reduction benefit. The MAX8732A/MAX8733A/MAX8734As’ pulse-skip- ping algorithm (SKIP = GND) initiates skip mode at the critical conduction point, so the inductor’s ...
Page 26
High-Efficiency, Quad-Output, Main Power- Supply Controllers for Notebook Computers V − ≤ R ESR × LIR I LOAD MAX where V is the peak-to-peak output voltage ripple. P-P The actual capacitance value required relates to the physical size ...
Page 27
High-Efficiency, Quad-Output, Main Power- Supply Controllers for Notebook Computers The maximum input capacitor RMS current for a single SMPS is given by: ( OUT _ ≈ RMS LOAD V When V+ ...
Page 28
High-Efficiency, Quad-Output, Main Power- Supply Controllers for Notebook Computers Rectifier Selection Current circulates from ground to the junction of both MOSFETs and the inductor when the high-side switch is off consequence, the polarity of the switching node is ...
Page 29
High-Efficiency, Quad-Output, Main Power- Supply Controllers for Notebook Computers the minimum V+ is MIN ) µ × ...
Page 30
High-Efficiency, Quad-Output, Main Power- Supply Controllers for Notebook Computers USE AGND PLANE TO: USE PGND PLANE TO: - BYPASS V AND REF - BYPASS LDO_ CC - TERMINATE EXTERNAL FB - CONNECT PGND TO THE TOPSIDE STAR GROUND DIVIDER (IF ...
Page 31
High-Efficiency, Quad-Output, Main Power- Supply Controllers for Notebook Computers • Make all pin-strap control input connections (SKIP, ILIM_, etc.) to GND the device. CC Layout Procedure 1) Place the power components first with ground ter- minals adjacent ...
Page 32
... High-Efficiency, Quad-Output, Main Power- Supply Controllers for Notebook Computers Ordering Information (continued) PIN- PART TEMP RANGE PA CKA GE MAX8734AEEI+ -40°C to +85°C 28 QSOP MAX8734AEEI -40°C to +85°C 28 QSOP +Denotes lead free package. 32 ______________________________________________________________________________________ Pin Configurations (continued) 5V/3V SWITCHING TOP VIEW FREQUENCY (kHz) ...
Page 33
... 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 © 2005 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products, Inc ...