EVAL5981:L5981, 1 A step-down switching regulator, evaluation board

The EVAL5981 demonstration board provides the design engineer with a fully functional step-down switching regulator with an output current of up to 1 A. The L5981 integrates STMicroelectronics step-down switching regulator, together with all the external components required for a typical application.

The rated voltage of the input capacitor and the Schottky diode rectifier repetitive peak reverse voltage are both 25 V, making the board capable of covering the entire 2.9 V - 18 V input voltage range of the L5981 device.

The board features an external resistor divider (R1 and R2) designed for an output voltage of 3.3 V.

The output voltage can be set to a level from 0.6 V up to the rated voltage of the output capacitor (16 V).

The compensation network on the demonstration board allows the use of MLCC as output filter to keep the loop stable. The inductor saturation current and forward current of the Schottky diode are within the current limit values.

The switching frequency on the demonstration board is set to 500 kHz by means of the R5 resistor connected to pin Fsw.

Key Features

  • Zero-load current operation
  • Low dropout operation: 100 % duty cycle
  • VFQFPN8 3 mm x 3 mm package
  • 1 A DC output current
  • Output voltage adjustable from 0.6 V to 16 V
  • 2.9 V to 18 V input voltage
  • Internal soft-start and inhibit
  • Over-current and thermal protection
  • 250 kHz switching frequency, programmable up to 1 MHz
Product Specifications
DescriptionVersionSize
DB0784: 1 A step-down switching regulator demonstration board based on the L59811.1204 KB
License Agreement
DescriptionVersionSize
Evaluation products license agreement1.0125 KB
Sample & Buy
Part NumberCore ProductUnit Price (US$) *QuantityECCN (EU)ECCN (US)Country of Origin
EVAL5981L598112.87-NECEAR99-
Quality & Reliability
Part NumberPackageGradeRoHS Compliance GradeMaterial Declaration**
EVAL5981CARDIndustrialNot compliant
1 A step-down switching regulator demonstration board based on the L5981 EVAL5981
ST-LINK/V2 in-circuit debugger/programmer for STM8 and STM32 ST-LINK-V2