MAX5082 MAXIM [Maxim Integrated Products], MAX5082 Datasheet

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... The MAX5082/MAX5083 are 250kHz PWM step-down DC-DC converters with an on-chip, 0.3Ω high-side switch. The input voltage range is 4.5V to 40V for the MAX5082 and 7.5V to 40V for the MAX5083. The output is adjustable from 1.23V to 32V and can deliver up to 1.5A of load current. Both devices utilize a voltage-mode control scheme for ...

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... REG, DVREG, SYNC to SGND ...............................-0.3V to +12V FB, COMP SGND ...........................-0. PGND (MAX5082 only)................( PGND (MAX5082 only) ................-0. Continuous current through internal power MOSFET (pins 11/12 connected together and pins 13/14 connected together) Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied ...

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... BST LX IN MAX5082 only, sinking 10mA MAX5082 only, relative to DVREG, sourcing 10mA MAX5082 only, sourcing 10mA Sinking 10mA I PFM I ILIM MAX5082 V REG MAX5083 V = 5.5V to 40V, MAX5082 9.0V to 40V, MAX5083 20mA REG V = 4.5V 20mA, MAX5082 IN REG V = 7.5V 20mA, MAX5083 IN REG Temperature rising = +25° ...

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... MAXPower Step-Down DC-DC Converters (V = 12V, see Figure 5 (MAX5082) and Figure 6 (MAX5083 UNDERVOLTAGE LOCKOUT HYSTERESIS vs. TEMPERATURE (MAX5082) 1.0 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0 -40 - 110 135 TEMPERATURE (°C ) SHUTDOWN SUPPLY CURRENT vs. INPUT VOLTAGE (MAX5082) 250 T = +85°C 225 T = +135° 200 175 150 T = -40°C ...

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... Figure 5 (MAX5082) and Figure 6 (MAX5083 MAXIMUM DUTY CYCLE vs. INPUT VOLTAGE (MAX5083) 100 INPUT VOLTAGE (V) TURN-ON/OFF WAVEFORM LOAD 2ms/div OUTPUT VOLTAGE vs. TEMPERATURE 3.40 MAX5082 3.38 3.36 3. LOAD 3.32 3.30 3. LOAD 3.26 3.24 3.22 3.20 -40 -15 ...

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... MAXPower Step-Down DC-DC Converters (V = 12V, see Figure 5 (MAX5082) and Figure 6 (MAX5083 EFFICIENCY vs. LOAD CURRENT 100 12V OUT 24V OUT 40V OUT 0 0.001 0.01 0.1 LOAD CURRENT (A) LX VOLTAGE AND INDUCTOR CURRENT 2µs/div 6 _______________________________________________________________________________________ Typical Operating Characteristics (continued) = +25° ...

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... Supply Input Connection. Connect to an external voltage source from 4.5V to 40V (MAX5082) or 13 7.5V to 40V (MAX5083). Internal Regulator Output. 5V output for the MAX5082 and 8V output for the MAX5083. Bypass 15 15 REG to SGND with at least a 1µF ceramic capacitor. Signal Ground Connection. Solder the exposed pad to a large SGND plane. Connect SGND ...

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... OSC 0.3V Figure 1. MAX5082 Simplified Block Diagram Internal Linear Regulator (REG) REG is the output terminal (MAX5082 (MAX5083) LDO which is powered from IN and pro- vides power to the IC. Connect REG externally to DVREG to provide power for the high-side MOSFET gate driver. Bypass REG to SGND with a ceramic capacitor of at least 1µ ...

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... REGOK SSA V REF CPWM CLK The MAX5082 features an internal charge pump to enhance the turn-on of the internal MOSFET, allowing for operation with input voltages down to 4.5V. Connect a flying capacitor (C diode from C+ to BST, as well as a bootstrap capacitor (C ) between BST and LX to provide the gate-drive BST voltage for the high-side n-channel DMOS switch ...

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... This causes the constant 10V/V across the input IN RAMP voltage range of 4.5V to 40V (MAX5082) or 7.5V to 40V (MAX5083) and the SYNC frequency range of 150kHz to 350kHz. Output Short-Circuit Protection The MAX5082/MAX5083 protects against an output short circuit by utilizing hiccup-mode protection. In hiccup ...

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... PEAK where I OUT_MAX cycle, and f The MAX5082/MAX5083 includes internal and external UVLO hysteresis and soft-start to avoid possible unin- tentional chattering during turn-on. However, use a bulk capacitor if the input source impedance is high. Use ) enough input capacitance at lower input voltages to I ...

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... RESPONSE controller. Compensation Design The MAX5082/MAX5083 use a voltage-mode control scheme that regulates the output voltage by comparing the error amplifier output (COMP) with an internal ramp to produce the required duty cycle. The output lowpass LC filter creates a double pole at the resonant frequen- cy, which has a gain drop of -40dB/decade ...

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OUT EA R4 REF GAIN CLOSED-LOOP (dB) GAIN Figure 3. Error Amplifier Compensation Circuit (Closed-Loop and Error-Amplifier Gain Plot) for Ceramic Capacitors Pick a value for ...

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... R 5 Power Dissipation The MAX5082/MAX5083 is available in a thermally enhanced package and can dissipate +70°C. When the die temperature reaches +160°C, the part shuts down and is allowed to cool. After the part cools by 20°C, the device restarts with a soft-start. ...

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... V IN 4.5V TO 40V R1 1.4MΩ C1 10µF R2 549kΩ C2 0.1µF PGND Figure 5. MAX5082 Typical Application Circuit V IN 7.5V TO 40V R1 1.4MΩ REG C1 10µF ON/OFF R2 301kΩ C2 0.1µF PGND Figure 6. MAX5083 Typical Application Circuit ______________________________________________________________________________________ 1.5A, 40V, MAXPower Step-Down C10 C3 0.1µF 0.1µ DVREG C- C+ BST ...

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... IN 14 REG 15 SGND ______________________________________________________________________________________ Typical Operating Circuits (continued DVREG BST LX MAX5083 FB SYNC SGND PGND SS COMP MAX5082 6 DVREG REG SYNC SGND TQFN C BST L1 V OUT PGND Pin Configurations ...

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For the latest package outline information www.maxim-ic.com/packages.) D D/2 MARKING XXXXX PIN # 1 I.D. C -DRAWING NOT TO SCALE- ______________________________________________________________________________________ 1.5A, 40V, MAXPower ...

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MAXPower Step-Down DC-DC Converters (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.) COMMON DIMENSIONS PKG. 16L 5x5 20L 5x5 SYMBOL MIN. NOM. MAX. ...