MAX16976 28V, 600mA Automotive Step-Down Converter with Low Operating Current General Description Features The MAX16976 is a 600mA current-mode step-down S Wide 3.5V to 28V Input Voltage Range converter with an integrated high-side switch. The device S 42V Input Transient Tolerance operates with input voltages from 3.5V to 28V while using S 5V Fixed or 1V to 10V Adjustable Output Voltage only 45FA quiescent current at no load. The switching S Integrated 600mA High-Side Switch frequency is adjustable from 220kHz to 1.0MHz by using an external resistor, and can be synchronized to an exter- S 220kHz to 1.0MHz Adjustable Switching Frequency nal clock. The devices output voltage is pin-selectable to S Frequency Synchronization Input a fixed 5V or adjustable from 1V to 10V using external S Internal Boost Diode resistors. The wide input voltage range makes the device ideal for automotive and industrial applications. S 45A Skip-Mode Operating Current The device operates in skip mode for reduced current S Less than 10A Shutdown Current consumption in light-load conditions. An adjustable S Adjustable Power-Good Output Level and Timing reset threshold helps keep microcontrollers alive down S 3.3V Logic Level to 42V Compatible Enable Input to the lowest specified input voltage. Protection features include cycle-by-cycle current limit, soft-start, overvolt- S Current-Limit, Thermal Shutdown, and age, and thermal shutdown with automatic recovery. Overvoltage Protection The device also features a power-good monitor to ease S -40C to +125C Automotive Temperature Range power-supply sequencing. The device operates over the -40C to +125C auto- Applications motive temperature range, and is available in a 16-pin Automotive QSOP package. Industrial Ordering Information appears at end of data sheet. Typical Application Circuit 3.5V TO 28V C C C IN1 IN2 IN3 C BST 47F 4.7F 0.1F 0.1F SUP SUPSW L1 V = 1.25V AT OUT EN BST 22H 600mA AT 400kHz LX FSYNC V OUT R FB1 C C OUT1 OUT2 COMP D1 C 25kI 47F 47F COMP1 OUT 5600pF C COMP2 MAX16976 R RESETI FOSC R OPEN COMP 61.9kI V BIAS 12kI FOSC R FB2 FB R RES 100kI 10kI BIAS RES C BIAS CRES 1F GND C PLACE C (0.1F) RIGHT NEXT TO SUP. CRES IN3 1nF For related parts and recommended products to use with this part, refer to: www.maximintegrated.com/MAX16976.related For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxims website at www.maximintegrated.com. 19-5802 Rev 1 10/14MAX16976 28V, 600mA Automotive Step-Down Converter with Low Operating Current ABSOLUTE MAXIMUM RATINGS SUP, SUPSW, LX, EN to GND ...............................-0.3V to +45V Continuous Power Dissipation (T = +70NC) A BST to GND ..........................................................-0.3V to +47V QSOP (derate 9.6 mW/NC above +70NC) .................771.5mW BST to LX ...............................................................-0.3V to +6V Operating Temperature Range ........................ -40NC to +125NC OUT to GND ..........................................................-0.3V to +12V Junction Temperature .....................................................+150NC SUP to SUPSW .....................................................-0.3V to +0.3V Storage Temperature Range ............................ -65NC to +150NC RESETI, FOSC, COMP, BIAS, Lead Temperature (soldering, 10s) ................................+300NC FSYNC, CRES, RES, FB to GND .........................-0.3V to +6V Soldering Temperature (reflow) ......................................+260NC Output Short-Circuit Duration ....................................Continuous Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings only, and functional opera- tion 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 THERMAL CHARACTERISTICS (Note 1) QSOP Junction-to-Ambient Thermal Resistance (q ) .....103.7C/W JA Note 1: Package thermal resistances were obtained using the method described in JEDEC specification JESD51-7, using a four- layer board. For detailed information on package thermal considerations, refer to www.maximintegrated.com/thermal-tutorial. ELECTRICAL CHARACTERISTICS (V = V = 14V, V = 14V, L1 = 22FH, C = 4.7FF, C = 100FF, C = 1FF, C = 0.1FF, C = 1nF, R = SUP SUPSW EN IN OUT BIAS BST CRES FOSC 61.9kI, T = T = -40NC to +125NC, unless otherwise noted. Typical values are at T = +25NC.) A J A PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS V , SUP Supply Voltage Normal operation 3.5 28 V V SUPSW Normal operation, no switching 2.9 mA Supply Current I SUP Skip mode, no load, V = 5V 45 FA OUT Shutdown Supply Current V = 0V 9 FA EN V = V = 6V to 42V, V < 3V or SUP SUPSW OUT BIAS Regulator Voltage V 4.7 5.0 5.3 V BIAS V > 5.5V, I = 0A (Note 2) OUT LOAD BIAS Undervoltage Lockout V V rising 2.95 3.15 3.35 V UVBIAS BIAS BIAS Undervoltage Hysteresis 550 mV Thermal-Shutdown Threshold +175 NC Thermal-Shutdown Threshold +15 NC Hysteresis OUTPUT VOLTAGE (OUT) Normal operation, V = V , I = FB BIAS LOAD 4.95 5 5.05 0.6A, T = +25C A Output Voltage V V OUT Normal operation, V = V , I = FB BIAS LOAD 4.9 5 5.1 0.6A, -40C P T P +125C A Skip-Mode Output Voltage V No load, V = V (Note 3) 4.9 5.05 5.2 V OUT SKIP FB BIAS V = 5V, V = V 30mA < I < OUT FB BIAS, LOAD Load Regulation 0.3 % 0.6A Line Regulation 6V < V < 28V 0.02 %/V SUP Maxim Integrated 2