EVALUATION KIT AVAILABLE Click here for production status of specific part numbers. MAX5080/MAX5081 1A, 40V, MAXPower Step-Down DC-DC Converters General Description Features The MAX5080/MAX5081 are 250kHz PWM step-down 4.5V to 40V (MAX5080) or 7.5V to 40V (MAX5081) Input Voltage Range DC-DC converters with an on-chip, 0.3 high-side switch. The input voltage range is 4.5V to 40V for the MAX5080 1A Output Current and 7.5V to 40V for the MAX5081. The output is adjustable V Range From 1.23V to 32V OUT from 1.23V to 32V and can deliver up to 1A of load current. Internal High-Side Switch Both devices utilize a voltage-mode control scheme for Fixed 250kHz Internal Oscillator good noise immunity in the high-voltage switching environ- ment and offer external compensation allowing for maxi- Automatic Switchover to Pulse-Skip Mode at Light Loads mum flexibility with a wide selection of inductor values and capacitor types. The switching frequency is internally fixed External Frequency Synchronization at 250kHz and can be synchronized to an external clock Thermal Shutdown and Short-Circuit Protection signal through the SYNC input. Light load efficiency is Operates Over the -40C to +125C Temperature improved by automatically switching to a pulse-skip mode. Range All devices include programmable undervoltage lock- Space-Saving (5mm x 5mm) High-Power 16-Pin out and soft-start. Protection features include cycle- TQFN Package by-cycle current limit, hiccup-mode output short-circuit protection, and thermal shutdown. Both devices are available in a space-saving, high-power (2.7W), 16-pin TQFN package and are rated for operation over the -40C to +125C temperature range. Ordering Information appear at end of data sheet. Applications FireWire Power Supplies Industrial FireWire is a registered trademark of Apple Computer, Inc. Distributed Power Typical Operating Circuits V C D1 IN F 4.5V TO 40V C BST IN DVREG C- C+ BST L1 LX V OUT R1 C6 REG C1 R3 D2 C5 MAX5080 R6 ON/OFF FB C8 SYNC SGND PGND SS COMP R2 R4 C7 R5 C2 C SS PGND PGND Typical Operating Circuits continued at end of data sheet. 19-3656 Rev 3 4/18MAX5080/MAX5081 1A, 40V, MAXPower Step-Down DC-DC Converters Absolute Maximum Ratings IN, ON/OFF to SGND ............................................-0.3V to +45V T = +125C ........................................................................3A J LX to SGND................................................-0.3V to (V + 0.3V) T = +150C ........................................................................2A IN J BST to SGND ..............................................-0.3V to (V + 12V) Continuous Power Dissipation* (T = +70C) IN A BST to LX ..............................................................-0.3V to +12V 16-Pin TQFN (derate 33.3mW/C above +70C) .....2666.7mW PGND to SGND .................................................... -0.3V to +0.3V 16-Pin TQFN ( ) ......................................................30C/W JA REG, DVREG, SYNC to SGND ............................-0.3V to +12V 16-Pin TQFN ( ) .....................................................1.7C/W JC FB, COMP, SS to SGND ........................-0.3V to (V + 0.3V) Operating Temperature Range ......................... -40C to +125C REG C+ to PGND (MAX5080 only) ............ (V - 0.3V) to +12V Maximum Junction Temperature .....................................+150C DVREG C- to PGND (MAX5080 only) ............ -0.3V to (V + 0.3V) Storage Temperature Range ............................ -60C to +150C DVREG Continuous current through internal power MOSFET (pins 11/12 Lead Temperature (soldering, 10s) .................................+300C connected together and pins 13/14 connected together) *As per JEDEC 51 Standard 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. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. Package Information PACKAGE TYPE: 16-PIN TQFN Package Code T1655+3 Outline Number 21-0140 Land Pattern 90-0072 For the latest package outline information and land patterns (footprints), go to www.maximintegrated.com/packages. Note that a +, , or - in the package code indicates RoHS status only. Package drawings may show a different suffix character, but the drawing pertains to the package regardless of RoHS status. Electrical Characteristics (V = V = 12V, V = V , V = PGND = SGND, T = T = -40C to +125C, unless otherwise noted. Typical values IN ON/OFF REG DVREG SYNC A J are at T = + 25C.) (Note 1) A PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS MAX5080 4.5 40 Input Voltage Range V V IN MAX5081 7.5 40 V rising, MAX5080 3.9 4.2 Undervoltage Lockout IN UVLO V Threshold V rising, MAX5081 6.8 7.3 IN MAX5080 0.4 Undervoltage Lockout UVLO V HYST Hysteresis MAX5081 0.7 V = 0V, MAX5080 10.5 Switching Supply Current FB I mA SW (PWM Operation) V = 0V, MAX5081 9.5 FB V = 12V, V = 3.3V, I = 1A 84 IN OUT OUT Efficiency % V = 4.5V, V = 3.3V, I = 1A IN OUT OUT 88 (MAX5080) MAX5080 1.4 2.5 No-Load Supply Current mA (PFM Operation) MAX5081 1.3 2.3 Shutdown Current I V = 0V, V = 40V 200 300 A SHDN ON/OFF ON/OFF CONTROL Input Voltage Threshold V V rising 1.20 1.23 1.25 V ON/OFF ON/OFF Input Voltage Hysteresis 0.12 V Input Bias Current V = 0 to 40V -250 +250 nA ON/OFF Maxim Integrated 2 www.maximintegrated.com