LM5155-Q1 2.2MHz Wide VIN Non-synchronous Boost/SEPIC/Flyback Controller | TI.com

LM5155-Q1 (PREVIEW) 2.2MHz Wide VIN Non-synchronous Boost/SEPIC/Flyback Controller


Sample Availability

Prototype samples are available (XLM5155QDSSTQ1 and XLM51551QDSSTQ1). Request now


The LM5155-Q1 device is a wide input range, non-synchronous boost controller that uses peak current mode control. The device can be used in boost, SEPIC, and flyback topologies.

The LM5155-Q1 device can start up from a 1-cell battery with a minimum of 2.97 V if the BIAS pin is connected to the VCC pin. It can operate with the input supply voltage as low as 1.5 V if the BIAS pin is greater than 3.5 V.

The internal VCC regulator also supports BIAS pin operation up to 45 V (50-V absolute maximum) for automotive load dump. The switching frequency is dynamically programmable with an external resistor from 100 kHz to 2.2 MHz. Switching at 2.2 MHz minimizes AM band interference and allows for a small solution size and fast transient response.

The device features a 1.5-A standard MOSFET driver and a low 100-mV current limit threshold. The device also supports the use of an external VCC supply to improve efficiency. Low operating current and pulse-skipping operation improve efficiency at light loads.

The device has built-in protection features such as cycle-by-cycle current limit, overvoltage protection, line UVLO, and thermal shutdown. Hiccup mode overload protection is available in the LM51551-Q1 device option. Additional features include low shutdown IQ, programmable soft start, programmable slope compensation, precision reference, power-good indicator, and external clock synchronization.


  • AEC-Q100 Qualified for Automotive Applications
    • Temperature Grade 1: –40°C to +125°C TA
  • Wide Input Operating Range for Car and Portable Battery Applications
    • 3.5-V to 45-V Operating Range
    • 2.97-V to 16-V When BIAS = VCC
    • Minimum Boost Supply Voltage 1.5 V When BIAS ≥ 3.5 V
    • Input Transient Protection up to 50 V
  • Minimized Battery Drain
    • Low Shutdown Current (IQ ≤ 2.6 µA )
    • Low Operating Current ( IQ ≤ 480 µA )
  • Small Solution Size and Low Cost
    • Maximum Switching Frequency of 2.2 MHz
    • 12-Pin WSON Package (3 mm × 2 mm) With Wettable Flanks
    • Integrated Error Amplifier Allows Primary-Side Regulation Without Optocoupler (Flyback)
    • Minimized Undershoot During Cranking (Start-stop Application)
  • Higher Efficiency With Low-Power Dissipation
    • 100-mV ±7% Low Current Limit Threshold
    • Strong 1.5-A Peak Standard MOSFET Driver
    • Supports External VCC Supply
  • Avoid AM Band Interference and Crosstalk
    • Optional Clock Synchronization
    • Dynamically Programmable Switching Frequency from 100 kHz to 2.2 MHz
  • Integrated Protection Features
    • Constant Peak Current Limiting Over Input Voltage
    • Optional Hiccup Mode Short-Circuit Protection (see the Device Comparison Table)
    • Programmable Line UVLO
    • OVP Protection
    • Thermal Shutdown
  • Accurate ±1% Accuracy Feedback Reference
  • Programmable Extra Slope Compensation
  • Adjustable Soft Start
  • PGOOD Indicator
  • Create a Custom Design Using the LM5155-Q1 With the WEBENCH® Power Designer

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Product Option
  Min   Max Range
Vin  V
Vout  V
Iout  A
Ambient Temp  °C -40 to 150°C


Compare all products in Boost controllers (external switch) Email Download to Excel
Part number Order Vin (Min) (V) Vin (Max) (V) Vout (Min) (V) Vout (Max) (V) Regulated outputs (#) Switching frequency (Min) (kHz) Switching frequency (Max) (kHz) Iq (Typ) (mA) Features Duty cycle (Max) (%) Operating temperature range (C) Rating Type Package Group
LM5155-Q1 Order now 1.5     45     1.5     300     1     100     2200     0.45     Adjustable Current Limit
Frequency Synchronization
Power Good
UVLO Adjustable    
93     -40 to 150     Automotive     Controller     WSON | 12    
LM25122-Q1 Order now 3     42     3     50     1     50     600     4     Enable
Frequency Synchronization
Phase Interleaving
Synchronous Rectification    
100     -40 to 125     Automotive     Controller     HTSSOP | 20    
LM3481-Q1 Order now 2.97     48     1.275     500     1     100     1000     3.7     Adjustable Current Limit
Frequency Synchronization
Light Load Efficiency
Pre-Bias Start-Up
UVLO Adjustable    
85     -40 to 125     Automotive     Controller     VSSOP | 10    
LM5022-Q1 Order now 3     60     1.25     300     1     170     2200     3.5     Enable
Frequency Synchronization
UVLO Adjustable    
90     -40 to 125     Automotive     Controller     VSSOP | 10    
LM5122-Q1 Order now 3     65     3     100     1     50     1000     4     Enable
Frequency Synchronization
Phase Interleaving
Synchronous Rectification
UVLO Adjustable    
100     -40 to 125     Automotive     Controller     HTSSOP | 20    
TPS40211-Q1 Samples not available 4.5     52     6.4     60     1     35     1000     0.53     Enable
Frequency Synchronization    
95     -40 to 125