Product details


Topology Boost, Buck Vin (Min) (V) 3 Vin (Max) (V) 85 Vout (Max) (V) 85 Vout (Min) (V) 6 Duty cycle (Max) (%) 99 Switching frequency (Min) (kHz) 50 Switching frequency (Max) (kHz) 500 Iq (Typ) (mA) 1 Features Adjustable Current Limit, Adjustable UVLO, Enable, Frequency Synchronization, Light Load Efficiency, Load Disconnect, Multiple Outputs, Phase Interleaving, Power Good, Synchronous Rectification, UVLO Adjustable Iout (Max) (A) 50 Operating temperature range (C) -40 to 150 Rating Automotive open-in-new Find other Buck-boost & inverting controllers (external switch)

Package | Pins | Size

HTQFP (PHP) 48 81 mm² 9 x 9 open-in-new Find other Buck-boost & inverting controllers (external switch)


  • AEC-Q100 qualified for automotive applications:
    • Device temperature grade 1: –40°C to +125°C ambient operating range
    • Device HBM ESD classification level 2
    • Device CDM ESD classification level C4B
  • Functional Safety-Capable
  • 100-V HV-port and 65-V LV-port max ratings
  • 1% Accurate bidirectional current regulation
  • 1% Accurate channel current monitoring
  • 5-A Peak half-bridge gate drivers
  • Programmable or adaptive dead-time control
  • Programmable oscillator frequency with optional synchronization to external clock
  • Independent channel enable control inputs
  • Analog and digital channel current control inputs
  • Programmable cycle-by-cycle peak current limit
  • HV and LV port overvoltage protection
  • Diode emulation prevents negative current
  • Programmable soft-start timer
  • MOSFET failure detect at start-up and circuit breaker control
  • Multiphase operation phase adding or dropping

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The LM5170-Q1 controller provides the essential high voltage and precision elements of a dual-channel bidirectional converter for automotive 48-V and 12-V dual battery systems. It regulates the average current flowing between the high voltage and low voltage ports in the direction designated by the DIR input signal. The current regulation level is programmed through analog or digital PWM inputs.

Dual-channel differential current sense amplifiers and dedicated channel current monitors achieve typical current accuracy of 1%. Robust 5-A half-bridge gate drivers are capable of driving parallel MOSFET switches delivering 500 W or more per channel. The diode emulation mode of the synchronous rectifiers prevents negative currents but also enables discontinuous mode operation for improved efficiency with light loads. Versatile protection features include cycle-by-cycle current limiting, overvoltage protection at both HV and LV ports, MOSFET failure detection and overtemperature protection.

An innovative average current mode control scheme maintains constant loop gain allowing a single R-C network to compensate both buck and boost conversion. The oscillator is adjustable up to 500 kHz and can synchronize to an external clock. Multiphase parallel operation is achieved by connecting two LM5170-Q1 controllers for 3- or 4-phase operation, or by synchronizing multiple controllers to phase-shifted clocks for a higher number of phases. A low state on the UVLO pin disables the LM5170-Q1 in a low current shutdown mode.

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Technical documentation

= Top documentation for this product selected by TI
No results found. Please clear your search and try again. View all 9
Type Title Date
* Datasheet LM5170-Q1 Multiphase Bidirectional Current Controller datasheet (Rev. C) Jun. 10, 2020
Functional safety information LM5170 and LM5170-Q1 Functional Safety, FIT Rate, and Failure Mode Distribution May 22, 2020
Application note Why use PSR‐flyback isolated converters in dual‐battery mHEV systems Mar. 19, 2020
Technical articles Taking a modular approach to high-precision, high-current battery test equipment Jun. 21, 2019
Technical articles Four-switch buck-boost layout tip No. 4: routing gate-drive and return paths Feb. 20, 2019
White paper Bridging 12 V and 48 V in dual-battery automotive systems Oct. 18, 2018
Technical articles Achieving highly accurate full-scale charge and discharge current control for high-cell Li-ion battery-formation testing Aug. 13, 2018
Technical articles How to charge and discharge battery test equipment Apr. 11, 2018
User guide LM5170-Q1 EVM User's Guide (Rev. A) Dec. 05, 2016

Design & development

For additional terms or required resources, click any title below to view the detail page where available.

Hardware development

The LM5170EVM-BIDIR is a high performance dual phase bi-directional converter ideal for 48V-12V dual battery system applications.  The two phases operate in 180degree interleaved operation, and they evenly share a max dc current of up to 60A.  When DIR is set to "1" the power flows from (...)
  • Buck Mode: 48V-port voltage range 6V to 75V;  12V-port voltge regulated at 14.5V
  • Boost Mode: 12V-port voltage range 3V to 48V;  48V-port voltge regulated at 50.5V
  • Max dc current into or out of the 12V-port is 60A
  • Built-in analog voltage loop control, while it also accept MCU digital voltage loop control (...)

Design tools & simulation

SNVMB14A.ZIP (154 KB) - PSpice Model
SNVMB67.TSC (592 KB) - TINA-TI Reference Design
SNVMB68.ZIP (132 KB) - TINA-TI Spice Model
PSpice® for TI design and simulation tool
PSPICE-FOR-TI — PSpice® for TI is a design and simulation environment that helps evaluate functionality of analog circuits. This full-featured, design and simulation suite uses an analog analysis engine from Cadence®. Available at no cost, PSpice for TI includes one of the largest model libraries in the (...)
  • Leverages Cadence PSpice Technology
  • Preinstalled library with a suite of digital models to enable worst-case timing analysis
  • Dynamic updates ensure you have access to most current device models
  • Optimized for simulation speed without loss of accuracy
  • Supports simultaneous analysis of multiple products
  • (...)
SNVC205.ZIP (630 KB)

Reference designs

参考设计 Download
2460-W bidirectional boost converter reference design for automotive applications
PMP22396 — This reference design is a 2460-W bidirectional boost converter for automotive applications. The circuit is powered from the nominal 12-V battery to provide an output voltage of 48 V at 51.25 A. The design uses two dual-phase synchronous bidirectional controllers operating at a switching frequency (...)
document-generic Schematic
参考设计 Download
Bidirectional DC-DC Converter Reference Design for 12-V/48-V Automotive Systems
TIDA-01168 — The TIDA-01168 reference design is a four-phase, bidirectional DC-DC converter development platform for 12-V/48-V automotive systems. The system uses two LM5170-Q1 current controllers and a TMS320F28027F microcontroller (MCU) for the power stage control. LM5170-Q1 subsystems use average current (...)
document-generic Schematic
参考设计 Download
48-V / 25-A negative-to-positive synchronous buck-boost reference design for power amplifiers
PMP21943 — This reference design is a negative-to-positive synchronous buck-boost converter for power amplifier applications. The circuit is powered from the nominal -48-V system source to provide an output voltage of +48 V at 25 A. The design uses two dual synchronous boost controllers for 4-phase operation (...)
document-generic Schematic
参考设计 Download
12-V / 100-A negative-to-positive synchronous buck-boost reference design for power amplifiers
PMP21867 — This reference design is a negative-to-positive synchronous buck-boost converter for power amplifier applications. The circuit is powered from the nominal -48-V system source to provide an output voltage of +12 V at 100 A. The design uses two dual synchronous boost controllers for 4-phase operation (...)
document-generic Schematic
参考设计 Download
Battery Tester Reference Design for High Current Applications
TIDA-01040 — Li-Ion battery formation and electrical testing require accurate voltage and current control, usually to better than ±0.05% over the specified temperature range.  This reference design proposes a solution for high-current (up to 50 A) battery tester applications supporting input (bus (...)
document-generic Schematic
参考设计 Download
Battery tester reference design for multi-phase high-precision 0.5 to 100 A battery formation
TIDA-01041 — This reference design provides a multi-phase solution for a wide range of current battery test applications. Leveraging the dual phase buck/boost controller LM5170's daisy chain configuration gives the design the ability to achieve 100A charging/discharging rates. Utilizing high accuracy constant (...)
document-generic Schematic
参考设计 Download
Modular battery tester reference design for 50-A, 100-A, and 200-A applications
TIDA-01042 — This reference design provides a modular battery test solution allowing users to have the flexibility to test batteries at different current levels with one design. This design leverages the TIDA-01041 reference design by providing two 100-A battery testers that can work independently or be (...)
document-generic Schematic
参考设计 Download
1000-W, Bidirectional, 12-V to 12-V Converter Reference Design
PMP15035 — This reference design is a dual-channel, bidirectional converter suitable for 12-V to 12-V, dual-battery system, automotive applications. This reference design has a wide input range (3 V to 40 V) and could give full load (1kW) in the input voltage from 9V to 18V by using two LM5170-Q1 controllers (...)
document-generic Schematic
参考设计 Download
50A, 0.05% Current Accuracy Power Reference Design for Battery Test Systems
PMP15038 — This reference design introduces a large current, highly accurate and bi-directional power solution used in battery test systems (BTS). It includes a LM5170EVM-BIDIR and a signal control board. The LM5170EVM-BIDIR is an evaluation board  to showcase the high performance of the dual-channel (...)
document-generic Schematic

CAD/CAE symbols

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