Datasheet LM25149-Q1 (Texas Instruments) - 7

LM25149-Q1 www.ti.com
SNVSBV6 – DECEMBER 2020 TJ = –40°C to +150°C, VIN = 8 V to 18 V. Typical values are at TJ = 25°C and VIN = 12 V (unless otherwise noted)
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
VVCCX-ON VCCX(ON) rising threshold 4.1 4.3 4.4 V VVCCX-HYST VCCX hysteresis voltage VVCCX = 5 V 130 mV RVCCX VCCX resistance VVCCX = 5 V 2 Ω
REFERENCE VOLTAGE
VFB Regulated FB voltage 795 800 808 mV
OUTPUT VOLTAGE (VOUT)
R V FB = 0 Ω, VIN = 3.8 V to 42 V, internal OUT-3.3V-INT 3.3-V output voltage setpoint 3.267 3.3 3.33 V COMP R V FB = 0 Ω, VIN = 3.8 V to 42 V, OUT-3.3V-EXT 3.3-V output voltage setpoint 3.267 3.3 3.33 V external COMP 5-V output voltage setpoint R V FB = 24.9 kΩ, VIN = 5.5 V to 42 V, OUT-5V-INT 4.95 5.0 5.05 V internal COMP 5-V output voltage setpoint R V FB = 24.9 kΩ, VIN = 5.5 V to 42 V, OUT-5V-EXT 4.95 5.0 5.05 V external COMP
TION
R V FB = 48.7 kΩ, VIN = 24 V to 42 V, OUT-12V-INT 12-V output setpoint 11.88 12 12.12 V Internal COMP R
MA
V FB = 48.7 kΩ, VIN = 24 V to 42 V, OUT-12V-EXT 12-V output setpoint 11.88 12 12.12 V external COMP COMP
R
RFB-OPT2 5-V output select 24.3 24.9 25.5 kΩ RFB-OPT3 12-V output select 47.5 48.7 49.9 kΩ
ERROR AMPLIFIER (COMP)
EA transconductance, external gm-EXTERNAL FB to COMP 1020 1200 µS compensation EA transconductance, internal FB to COMP, EXTCOMP 100 kΩ to gm-INTERNAL 30 µS compensation VDDA
NCE INFO
I
A
FB Error amplifier input bias current 75 nA
V
VCOMP-CLAMP COMP clamp voltage VFB = 0 V 2.1 V ICOMP-SRC EA source current VCOMP = 1 V, VFB = 0.4 V 180 µA
AD
ICOMP-SINK EA sink current VCOMP = 1 V, VFB = 0.8 V 160 µA RCOMP Internal compensation EXTCOMP 100 kΩ to VDDA 400 kΩ CCOMP Internal compensation EXTCOMP 100 kΩ to VDDA 50 pF CCOMP-HF Internal compensation EXTCOMP 100 kΩ to VDDA 1 pF
PULSE FREQUENCY MODULATION (PFM)
VPFM-LO PFM detection threshold low 0.8 V VPFM-HI PFM decection threshold high 2.0 V VZC-SW Zero-cross threshold -5.5 mV PFM = VDDA, 1000 SW cycles after VZC-DIS Zero-cross threshold disable 100 mV first HO pulse R F RT = 10 kΩ, ± 20% of the nominal SYNCIN3 Frequency sync range 1760 2640 kHz oscillator frequency Minimum pulse width of external tSYNC-MIN3 20 250 ns synchronization signal Delay from PFM faling edge to HO tSYNCIN-HO 25 ns rising edge tPFM-FILTER SYNCIN to PFM mode 15 30 µs
DUAL RANDOM SPREAD SPECTRUM (DRSS)
Distance from the nominal switching ΔfC 7.8 % frequency fm Modulation frequency 13 21 kHz
SWITCHING FREQUENCY
Copyright © 2020 Texas Instruments Incorporated Submit Document Feedback 7 Product Folder Links: LM25149-Q1 Document Outline 1 Features 2 Applications 3 Description Table of Contents 4 Revision History 5 Description (continued) 6 Pin Configuration and Functions 6.1 Wettable Flanks 7 Specifications 7.1 Absolute Maximum Ratings 7.2 ESD Ratings  7.3 Recommended Operating Conditions 7.4 Thermal Information 7.5 Electrical Characteristics 7.6 Active EMI Filter 8 Detailed Description 8.1 Overview 8.2 Functional Block Diagram 8.3 Feature Description 8.3.1 Input Voltage Range (VIN) 8.3.2 High-Voltage Bias Supply Regulator (VCC, VCCX, VDDA) 8.3.3 Enable (EN) 8.3.4 Power Good Monitor (PG) 8.3.5 Switching Frequency (RT) 8.3.6 Active EMI Filter 8.3.7 Dual Random Spread Spectrum (DRSS) 8.3.8 Soft-Start 8.3.9 Output Voltage Setpoint (FB) 8.3.10 Minimum Controllable On-Time 8.3.11 Error Amplifier and PWM Comparator (FB, EXTCOMP) 8.3.12 Slope Compensation 8.3.13 Inductor Current Sense (ISNS+, VOUT) 8.3.13.1 Shunt Current Sensing 8.3.13.2 Inductor DCR Current Sensing 8.3.14 Hiccup Mode Current Limiting 8.3.15 High-Side and Low-Side Gate Drivers (HO, LO) 8.3.16 Output Configurations (CNFG) 8.3.17 Single-Output Two-phase Operation 8.4 Device Functional Modes 8.4.1 Standby Modes 8.4.2 Pulse Frequency Modulation and Synchronization (PFM/SYNC) 8.4.3 Thermal Shutdown 9 Application and Implementation 9.1 Application Information 9.1.1 Power Train Components 9.1.1.1 Buck Inductor 9.1.1.2 Output Capacitors 9.1.1.3 Input Capacitors 9.1.1.4 Power MOSFETs 9.1.1.5 EMI Filter 9.1.2 Error Amplifier and Compensation 9.2 Typical Application 9.2.1 Design Requirements 9.2.2 Detailed Design Procedure 9.2.2.1 Custom Design With WEBENCH® Tools 9.2.2.2 Custom Design With Excel Quickstart Tool 9.2.2.3 Buck Inductor 9.2.2.4 Current-Sense Resistance 9.2.2.5 Output Capacitors 9.2.2.6 Input Capacitors 9.2.2.7 Frequency Set Resistor 9.2.2.8 Feedback Resistors 9.2.2.9 Compensation Components 9.2.2.10 Active EMI Components 9.2.3 Application Curves 10 Power Supply Recommendations 11 Layout 11.1 Layout Guidelines 11.1.1 Power Stage Layout 11.1.2 Gate-Drive Layout 11.1.3 PWM Controller Layout 11.1.4 Active EMI Layout 11.1.5 Thermal Design and Layout 11.1.6 Ground Plane Design 11.2 Layout Example 12 Device and Documentation Support 12.1 Device Support 12.1.1 Development Support 12.1.2 Custom Design With WEBENCH® Tools 12.2 Documentation Support 12.2.1 Related Documentation 12.2.1.1 PCB Layout Resources 12.2.1.2 Thermal Design Resources 12.3 Receiving Notification of Documentation Updates 12.4 Support Resources 12.5 Trademarks 12.6 Electrostatic Discharge Caution 12.7 Glossary 13 Mechanical, Packaging, and Orderable Information