Product overview
Description
The ST1S50 device is a 500 kHz fixed frequency PWM synchronous step-down regulator. The ST1S50 operates from 4.0 V to 18 V input, while it regulates an output voltage as low as 0.8 V and up to 0.88 x VIN.
The ST1S50 device integrates a 95 mΩ high-side switch and a 69 mΩ synchronous rectifier allowing very high efficiency with very low output voltages.
The peak current mode control with a special PFM mode enables high efficiency at a light load.
The ST1S50 device is available in a VFDFPN10 3 x 3 x 1 mm - 10 leads package.
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All features
- 4 A output current
- 4.0 V to 18 V input voltage
- Output voltage adjustable from 0.8 V to 0.88 x VIN
- 500 kHz switching frequency
- High efficiency at light load
- Programmable soft-start and enable
- Integrated 95 mΩ and 69 mΩ power MOSFETs
- All ceramic capacitor
- Power Good
- Cycle-by-cycle current limiting
- Short-circuit protection
- VFDFPN10 3 x 3 x 1 mm - 10 L
eDesignSuite
eDesignSuite is a comprehensive set of easy-to-use design-aid utilities ready to help you streamline the system development process with a wide range of ST products.
Power Management Design Center
Thermal-electrical Simulators for Components
Signal Conditioning Design Tool
NFC/RFID Calculators
Choose design tool: 
Power Management Design Center
Power Supply Design Tool
• SMPS design, by topology, by type and by product
• PFC design with analog and digitial control
• Supports various PCB configurations
Choose type: DC/DC AC/DC Solar Battery Charger
Power Management Design Center
LED Lighting Design Tool
• Handles AC-DC and DC-DC design in common topologies
• Displays interactive and annotated schematic
• Provides current/voltage graphs, Bode plots, efficiency curves and power-loss data
Choose type: DC/DC AC/DC
Power Management Design Center
Digital Power Workbench
• Provides a step-by-step optimized design of power section and control loop
• Generates the STM32Cube embedded software package for custom applications and allows firmware project generation, compatible with multiple STM32 IDEs
Power Management Design Center
Power Tree Designer
• Specify input/output power for each node in the tree
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Thermal-electrical Simulators for Components
AC Switches Simulator
• Select ratings and application waveforms
• Get junction temperature and blocking voltage graphs
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Thermal-electrical Simulators for Components
Rectifier Diodes Simulator
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• Estimate power losses
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Thermal-electrical Simulators for Components
STPOWER Studio
• Supports long mission profiles
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Thermal-electrical Simulators for Components
Twister Sim
• Help select the right ViPOWER Automotive power device
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• Supports various PCB configurations
Thermal-electrical Simulators for Components
TVS Simulator
• Specify system ratings and surge waveform
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Thermal-electrical Simulators for Components
Estimate
• Build simple schematics and firmware inputs in minutes
• Quickly generate reliable estimates of battery life, system power consumption and bill of materials costs
Thermal-electrical Simulators for Components
PCB Thermal Simulator
• Thermal analysis of a PCB from Gerber files.
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• Powerful server-side engine for rendering and simulation.
• Thermal results shown graphically via 2D table.
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Signal Conditioning Design Tool
Active Filters
• Handles multi-stage-designs and common topologies
• Returns circuit component values
• Provides gain, phase and group delay graphs
• Low Pass, High Pass and Band Pass
Signal Conditioning Design Tool
Comparators
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• Returns circuit components values
• Provides I/O signal waveforms
• Inverting, Non Inverting, Window
Signal Conditioning Design Tool
Low side Current Sensing
• Returns circuit component values
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Signal Conditioning Design Tool
High side Current Sensing
• Provides current error graphs.
• Help to select the right High side current sensing and shunt devices.
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NFC/RFID Calculators
NFC Inductance
• Input geometry and substrate properties
• Get antenna impedance
NFC/RFID Calculators
UHF Link Budget
• Enter forward and reverse link characteristics
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NFC/RFID Calculators
NFC Tuning Circuit
• Enter antenna parameter and matching target
• Select the topology of the matching network
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