MAX1956ETI+ Maxim Integrated Products, MAX1956ETI+ Datasheet
MAX1956ETI+
Specifications of MAX1956ETI+
Related parts for MAX1956ETI+
MAX1956ETI+ Summary of contents
Page 1
... TO 5.5V OUTPUT 1 0. 25A MARGINING ________________________________________________________________ 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. o Operates from a 1.6V to 5.5V Supply (MAX1956) o 0.5% Output Accuracy o 0. 25A per Phase Output Current ...
Page 2
Input, 0.5% Accurate, Dual 180° Out-of-Phase Step-Down Controllers ABSOLUTE MAXIMUM RATINGS IN, AVDD, SYNC, EN, ILIM_, FB_, SEQ to GND.......-0.3V to +6V COMP_, REF to GND..............................-0. LXB to GND ..............................................-0. DL_ to GND ...
Page 3
Input, 0.5% Accurate, Dual 180° Out-of-Phase Step-Down Controllers ELECTRICAL CHARACTERISTICS (continued 3.3V 5V VDD AVDD wise noted. Typical values are +25°C.) A PARAMETER ...
Page 4
Input, 0.5% Accurate, Dual 180° Out-of-Phase Step-Down Controllers ELECTRICAL CHARACTERISTICS ( 3.3V 5V; PGND = GND = VDD AVDD noted.) (Note 5) PARAMETER MAX1955 IN Input ...
Page 5
Input, 0.5% Accurate, Dual 180° Out-of-Phase Step-Down Controllers ELECTRICAL CHARACTERISTICS (continued 3.3V 5V; PGND = GND = VDD AVDD noted.) (Note 5) PARAMETER DH_ Gate-Driver ...
Page 6
Input, 0.5% Accurate, Dual 180° Out-of-Phase Step-Down Controllers (Circuit of Figure +25°C, unless otherwise noted.) A EFFICIENCY vs. LOAD CURRENT WITH 3.3V INPUT 100 V = 1.8V OUT V = 2.5V OUT 90 80 ...
Page 7
Input, 0.5% Accurate, Dual 180° Out-of-Phase Step-Down Controllers (Circuit of Figure +25°C, unless otherwise noted.) A OUTPUT VOLTAGE vs. INPUT VOLTAGE WITH 25A LOAD 3 2.5V WITH 20A LOAD OUT 2.5 DEVICE ...
Page 8
Input, 0.5% Accurate, Dual 180° Out-of-Phase Step-Down Controllers (Circuit of Figure +25°C, unless otherwise noted LOAD TO SHORT CIRCUIT MAX1955/56 toc19 V 1V/div OUT 10A/div I L 40µs/div LOW-OUTPUT MARGINING MAX1955/56 toc22 ...
Page 9
Input, 0.5% Accurate, Dual 180° Out-of-Phase Step-Down Controllers PIN NAME Enable and Voltage Margining Input. Connect for normal operation or connect to GND for shutdown Set V = (1/3 nominal ...
Page 10
Input, 0.5% Accurate, Dual 180° Out-of-Phase Step-Down Controllers GND GND1 COMP1 FB1 CURRENT LIMIT AND SHUTDOWN EN SYNC ( SEQ COMP2 FB2 Figure 1. Functional Diagram Detailed Description The MAX1955/MAX1956 are dual-output, fixed-frequency, ...
Page 11
Input, 0.5% Accurate, Dual 180° Out-of-Phase Step-Down Controllers Output voltage margining shifts the output voltage by ±4% from the nominal value to simplify system testing. Outputs also can be powered up and down in select- able sequences ...
Page 12
Input, 0.5% Accurate, Dual 180° Out-of-Phase Step-Down Controllers Foldback Current Limit Foldback current limit is used to reduce power dissipa- tion during overload and short-circuit conditions. This is accomplished by lowering the current-limit threshold as the output ...
Page 13
Input, 0.5% Accurate, Dual 180° Out-of-Phase Step-Down Controllers Synchronization An external clock of 1080kHz to 1320kHz at SYNC forces the controller to switch at half of this clock fre- quency. DH1 and DH2 positive-going edges alternately synchronize ...
Page 14
Input, 0.5% Accurate, Dual 180° Out-of-Phase Step-Down Controllers Design Procedure Setting the Output Voltage Output voltage is set with a resistor-divider, as shown in Figure 4. The output voltage can be set to as low as 0.8V. ...
Page 15
Input, 0.5% Accurate, Dual 180° Out-of-Phase Step-Down Controllers The output voltage ripple due to the ESL of the output capacitor is: RIPPLE ESL ( ) IN ESL I is the peak-to-peak ...
Page 16
Input, 0.5% Accurate, Dual 180° Out-of-Phase Step-Down Controllers Figure 5. Typical Application Circuit 16 ______________________________________________________________________________________ ...
Page 17
Input, 0.5% Accurate, Dual 180° Out-of-Phase Step-Down Controllers Figure 6. Independent Output On/Off Control ______________________________________________________________________________________ 17 ...
Page 18
Input, 0.5% Accurate, Dual 180° Out-of-Phase Step-Down Controllers Use DS(ON) J(MAX) = × × × HSSW IN LOAD SW where I is the average DH driver output-current GATE determined ...
Page 19
Input, 0.5% Accurate, Dual 180° Out-of-Phase Step-Down Controllers must compensate for this gain drop and phase shift in order to achieve a stable high-bandwidth closed-loop system. The basic regulator loop consists of a power modulator, an output ...
Page 20
Input, 0.5% Accurate, Dual 180° Out-of-Phase Step-Down Controllers another high-frequency pole ( the error-amplifier PHF response. This pole should be greater than 100 times the error-amplifier zero frequency in order to have neg- ligible impact ...
Page 21
Input, 0.5% Accurate, Dual 180° Out-of-Phase Step-Down Controllers Applications Information PC Board Layout Guidelines Careful PC board layout is important in any switching regulator. The switching power stage requires particular attention. Follow these guidelines for good PC ...
Page 22
... 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. 22 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 © 2003 Maxim Integrated Products D2 ...