Datasheet MAX17577, MAX17578 (Maxim) - 3

link to page 4 link to page 4 MAX17577, MAX17578 4.5V to 60V, 1A High-Efficiency, Synchronous, Inverting Output DC-DC Converters
Electrical Characteristics (continued)
(VIN = VEN/UVLO = 24V, CVCC = 2.2μF, VFB = 1V, RT/SYNC = LX = SS = RESET = Open, VBST to VLX = 5V, VGND = VSOUT = VOUT = 0V, TA = -40°C to +125°C. Typical values are at TA = +25°C. All voltages are referenced to SOUT, unless otherwise noted.) (Note 3)
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS LDO (VCC)
1mA < IVCC < 15mA 4.75 5 5.25 VCC Output Voltage VCC V 6V ≤ VIN ≤ 60V; IVCC = 1mA 4.75 5 5.25 VCC Current Limit IVCC_MAX VCC = 4.3V, VIN = 6.5V 25 60 100 mA VCC Dropout VCC_DO VIN = 4.5V, IVCC=15mA 0.35 V VCC_UVR VCC rising 4.05 4.2 4.3 VCC UVLO V VCC_UVF VCC falling 3.65 3.8 3.9
HIGH-SIDE AND LOW-SIDE MOSFETS
High-Side nMOSFET R On-Resistance DS-ONH ILX = 0.3A, Sourcing 330 660 mΩ Low-Side nMOSFET R On-Resistance DS-ONL ILX = 0.3A,Sinking 163 325 mΩ V LX Leakage Current I LX = (VOUT + 1V) to (VIN - 1V), TA = LXLKG -2 +2 μA +25°C
SOFT-START (SS)
Charging Current ISS VSS = 0.5V 4.7 5 5.3 μA
FEEDBACK (FB)
FB Regulation Voltage VFB-REG 0.888 0.9 0.912 V FB Input-Bias Current IFB 0 ≤ VFB ≤ 1V, TA = +25°C -50 +50 nA
CURRENT LIMIT
Peak Current-Limit I Threshold PEAK-LIMIT 2.15 2.4 2.65 A Runaway Current-Limit IRUNAWAY- 2.3 2.65 3 A Threshold LIMIT Sink Current-Limit MAX17577 -0.9 I A Threshold SINK-LIMIT MAX17578 0
SWITCHING FREQUENCY AND EXTERNAL CLOCK SYNCHRONIZATION (RT/SYNC)
RRT/SYNC = Open 525 600 675 RRT/SYNC = 6.81kΩ 365 400 425 Switching Frequency fSW kHz RRT/SYNC = 10.5kΩ 565 600 635 RRT/SYNC = 43.2kΩ 1980 2200 2420 Minimum On-Time tON_MIN 60 80 ns Minimum Off-Time tOFF_MIN 140 150 160 ns LX Dead Time tLX-DT 5 ns VFB Hiccup Threshold VFB-HICF VFB Falling 0.55 0.58 0.61 V Hiccup Timeout (Note 4) 32768 cycles Bias Current IRT_BIAS 60 μA SYNC Frequency- 1.1 x 1.4 x f kHz Capture Range SW set by RRT/SYNC fSW fSW www.maximintegrated.com Maxim Integrated | 3 Document Outline General Description Applications Benefits and Features Simplified Application Circuit Absolute Maximum Ratings Package Information TDFN Electrical Characteristics Electrical Characteristics (continued) Typical Operating Characteristics Typical Operating Characteristics (continued) Pin Configuration MAX17577, MAX17578 Pin Description Pin Description (continued) Functional Diagrams MAX17577/MAX17578 Block Diagram Detailed Description Switching Frequency and External Clock Synchronization Linear Regulator (VCC) Operating Input-Voltage Range Overcurrent Protection (OCP)/Hiccup Mode RESET Output Prebiased Output Thermal-Shutdown Protection Applications Information Inductor Selection Load Current Capability (IOUT(MAX)) Input Capacitor Selection Output-Capacitor Selection Soft-Start Capacitor Selection Adjusting Output Voltage Setting the Input Undervoltage-Lockout Level Inductive Output Short-Circuit Protection Power Dissipation PCB Layout Guidelines Typical Application Circuits -5V Typical Application Circuits Typical Application Circuits (continued) -12V Typical Application Circuit Ordering Information Revision History