Product overview
Description
The ST1S31 device is an internally compensated 1.5 MHz fixed-frequency PWM synchronous step-down regulator. The ST1S31 operates from 2.8 V to 5.5 V input, while it regulates an output voltage as low as 0.8 V and up to VIN.
The ST1S31 integrates a 60 mΩ high-side switch and a 45 mΩ synchronous rectifier allowing very high efficiency with very low output voltages.
The peak current mode control with internal compensation delivers a very compact solution with a minimum component count.
The ST1S31 device is available in 3 mm x 3 mm, 8 lead VFDFPN and SO8 packages.
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All features
- 3 A DC output current
- 2.8 V to 5.5 V input voltage
- Output voltage adjustable from 0.8 V
- 1.5 MHz switching frequency
- Internal soft-start and enable
- Integrated 60 mΩ and 45 mΩ power MOSFETs
- All ceramic capacitor
- Power Good (POR)
- Cycle-by-cycle current limiting
- Current foldback short-circuit protection
- VFDFPN 3 x 3 - 8L, SO8 packages
eDesignSuite
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Power Tree Designer
Specify input/output power for each node in the tree Check for consistency Design each individual node Start your design with the ST1S31 now
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STMicroelectronics - ST1S31
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Quality and Reliability
| Part Number | Marketing Status | Package | Grade | RoHS Compliance Grade | Material Declaration** |
|---|---|---|---|---|---|
| ST1S31D-R | NRND | SO-8 | Industrial | Ecopack2 | |
| ST1S31PUR | Active | VFDFPN 8 3x3x1.0 | Industrial | Ecopack2 |
(**) The Material Declaration forms available on st.com may be generic documents based on the most commonly used package within a package family. For this reason, they may not be 100% accurate for a specific device. Please contact our sales support for information on specific devices.
Sample & Buy
| Part Number | Order from distributors | Order from ST | Marketing Status | ECCN (US) | ECCN (EU) | Packing Type | Package | Temperature (°C) | Country of Origin | Budgetary Price (US$)*/Qty | ||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| min | max | |||||||||||
| ST1S31D-R | distributors No availability of distributors reported, please contact our sales office | NRND | EAR99 | NEC | Tape and Reel | SO-8 | - | - | CHINA | | ||
| ST1S31PUR | distributors No availability of distributors reported, please contact our sales office | Active | EAR99 | NEC | Tape and Reel | VFDFPN 8 3x3x1.0 | - | - | MALAYSIA | | ||
(*) Suggested Resale Price (USD) per defined quantity for BUDGETARY USE ONLY. For quotes, prices in local currency, please contact your local ST Sales Office or our Distributors