SNVSAA1B July 2015 – November 2017 LM46000-Q1
PRODUCTION DATA.
- 1 Features
- 2 Applications
- 3 Description
- 4 Revision History
- 5 Pin Configuration and Functions
- 6 Specifications
-
7 Detailed Description
- 7.1 Overview
- 7.2 Functional Block Diagram
- 7.3
Feature Description
- 7.3.1 Fixed Frequency Peak Current Mode Controlled Step-Down Regulator
- 7.3.2 Light Load Operation
- 7.3.3 Adjustable Output Voltage
- 7.3.4 Enable (ENABLE)
- 7.3.5 VCC, UVLO, and BIAS
- 7.3.6 Soft Start and Voltage Tracking (SS/TRK)
- 7.3.7 Switching Frequency (RT) and Synchronization (SYNC)
- 7.3.8 Minimum ON-Time, Minimum OFF-Time and Frequency Foldback at Drop-Out Conditions
- 7.3.9 Internal Compensation and CFF
- 7.3.10 Bootstrap Voltage (BOOT)
- 7.3.11 Power Good (PGOOD)
- 7.3.12 Overcurrent and Short-Circuit Protection
- 7.3.13 Thermal Shutdown
- 7.4 Device Functional Modes
-
8 Applications and Implementation
- 8.1 Application Information
- 8.2
Typical Applications
- 8.2.1 Design Requirements
- 8.2.2
Detailed Design Procedure
- 8.2.2.1 Custom Design With WEBENCH® Tools
- 8.2.2.2 Output Voltage Setpoint
- 8.2.2.3 Switching Frequency
- 8.2.2.4 Input Capacitors
- 8.2.2.5 Inductor Selection
- 8.2.2.6 Output Capacitor Selection
- 8.2.2.7 Feed-Forward Capacitor
- 8.2.2.8 Bootstrap Capacitors
- 8.2.2.9 VCC Capacitor
- 8.2.2.10 BIAS Capacitors
- 8.2.2.11 Soft-Start Capacitors
- 8.2.2.12 Undervoltage Lockout Setpoint
- 8.2.2.13 PGOOD
- 8.2.3 Application Performance Curves
- 9 Power Supply Recommendations
- 10Layout
- 11Device and Documentation Support
- 12Mechanical, Packaging, and Orderable Information
Package Options
Mechanical Data (Package|Pins)
- PWP|16
Thermal pad, mechanical data (Package|Pins)
Orderable Information
1 Features
- Qualified for Automotive Applications
- AEC-Q100 Qualified With the Following Results:
- Device Temperature Grade 1: –40°C to +125°C Operating Junction Temperature
- 24-µA Quiescent Current in Regulation
- High Efficiency at Light Load (DCM and PFM)
- Tested to EN55022/CISPR 22 EMI Standards
- Integrated Synchronous Rectification
- Adjustable Frequency Range: 200 kHz to 2.2 MHz (500 kHz default)
- Frequency Synchronization to External Clock
- Internal Compensation
- Stable With Almost Any Combination of Ceramic, Polymer, Tantalum, and Aluminum Capacitors
- Power-Good Flag
- Soft Start into Pre-Biased Load
- Internal Soft Start: 4.1 ms
- Extendable Soft-Start Time by External Capacitor
- Output Voltage Tracking Capability
- Precision Enable to Program System UVLO
- Output Short-Circuit Protection With Hiccup Mode
- Overtemperature Thermal Shutdown Protection
- Create a Custom Design Using the LM46000-Q1 With the WEBENCH® Power Designer
2 Applications
- Sub-AM Band 12 V and 24 V Automotive
- Telecommunications Systems
- Commercial Vehicle Power Supplies
- General Purpose Wide VIN Regulation
- High Efficiency Point-Of-Load Regulation
3 Description
The LM46000-Q1 regulator is an easy-to-use synchronous step-down DC-DC converter capable of driving up to 500 mA of load current from an input voltage range of 3.5 V to 60 V. The LM46000-Q1 provides exceptional efficiency, output accuracy and dropout voltage in a very small solution size. An extended family is available in 1-A and 2-A load current options in pin-to-pin compatible packages. Peak current mode control is employed to achieve simple control loop compensation and cycle-by-cycle current limiting. Optional features such as programmable switching frequency, synchronization, power-good flag, precision enable, internal soft start, extendable soft start, and tracking provide a flexible and easy-to-use platform for a wide range of applications. Discontinuous conduction and automatic frequency modulation at light loads improve light load efficiency. The family requires few external components and pin arrangement allows simple, optimum PCB layout. Protection features include thermal shutdown, VCC undervoltage lockout, cycle-by-cycle current limit, and output short-circuit protection. The LM46000-Q1 device is available in the 16-pin HTSSOP (PWP) package (6.6 mm × 5.1 mm × 1.2 mm) with 0.65-mm lead pitch. The device is pin-to-pin compatible with the LM4360x and LM4600x families. The LM46000A-Q1 version is optimized for PFM operation and recommended for new designs.
Device Information(1)
| PART NUMBER | PACKAGE | BODY SIZE (NOM) |
|---|---|---|
| LM46000-Q1, LM46000A-Q1 | HTSSOP (16) | 6.60 mm × 5.10 mm |
- For all available packages, see the orderable addendum at the end of the data sheet.
space
space
space
Simplified Schematic
Radiated Emission Graph
VOUT = 3.3 V, VIN = 24 V, FS = 500 kHz, IOUT = 0.5 A
