Product overview
Description
The ST1S12 is a step down DC-DC converter optimized for powering low-voltage digital cores in HDD applications and, generally, to replace the high current linear solution when the power dissipation may cause high heating of the application environment. It provides up to 0.7 A over an input voltage range of 2.5 V to 5.5 V. A high switching frequency (1.7 MHz) allows the use of tiny surface-mount components. In addition to the resistor divider to set the output voltage value, only an inductor and two capacitors are required. Moreover, a low output ripple is guaranteed by the current mode PWM topology and by the use of low ESR SMD ceramic capacitors. The device is thermally protected and the current is limited to prevent damage due to accidental short-circuit. The ST1S12 is available in the TSOT23-5L package.
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All features
- Step-down current mode PWM (1.7 MHz) DC-DC converter
- 3% DC output voltage tolerance
- Synchronous rectification
- Fixed output voltage 1.2 V, 1.8 V, and ADJ (available on request 1.5 V, 2.5 V and 3.3 V)
- Enable function
- Internal soft start
- Typical efficiency: > 90%
- 0.7 A output current capability
- Not switching quiescent current: max 650 μA over temperature range
- RDSONtyp. 250 mΩ and 400 mΩ
- Uses tiny capacitors and inductors
- Operative junction temp. -40 °C to 125 °C
- Available in TSOT23-5L package
Circuit Diagram
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Active0.7 A / 1.2 V synchronous buck converter with enable function based on the ST1S12XX
Power supplies and converters -- STEVAL-ISA055V1Description:
0.7 A / 1.2 V synchronous buck converter with enable function based on the ST1S12XX
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EDA Symbols, Footprints and 3D Models
STMicroelectronics - ST1S12XX
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3D models
Quality and Reliability
Part Number | Marketing Status | Package | Grade | RoHS Compliance Grade | Material Declaration** |
---|---|---|---|---|---|
ST1S12G12R | Active | TSOT23-5L | Industrial | Ecopack2 | |
ST1S12G18R | Active | TSOT23-5L | Industrial | Ecopack2 | |
ST1S12GR | Active | TSOT23-5L | Industrial | Ecopack2 |
Marketing Status
Package
TSOT23-5L
Grade
Industrial
RoHS Compliance Grade
Ecopack2
Marketing Status
Package
TSOT23-5L
Grade
Industrial
RoHS Compliance Grade
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 | Marketing Status | Budgetary Price (US$)*/Qty | Order from ST | Order from distributors | Package | Packing Type | RoHS | Country of Origin | ECCN (US) | ECCN (EU) | Operating temperature (°C) | Operating Temperature (°C) (max) | ||||||||||||||||||||||||||||||||||||
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min | max | |||||||||||||||||||||||||||||||||||||||||||||||
ST1S12G18R | Active | 0.3961 / 1k | Available at 2 distributors Distributor availability of ST1S12G18R
Distributor reported inventory date: 3/3/2025 | | | | Buy from Distributor | | TSOT23-5L | Tape and Reel | MALAYSIA | EAR99 | NEC | -40 | 125 | |||||||||||||||||||||||||||||||||
ST1S12GR | Active | 0.3961 / 1k | Available at 5 distributors Distributor availability of ST1S12GR
Distributor reported inventory date: 3/3/2025 | | | | Buy from Distributor | | TSOT23-5L | Tape and Reel | MALAYSIA | EAR99 | NEC | -40 | 125 | |||||||||||||||||||||||||||||||||
ST1S12G12R | Active | 0.3961 / 1k | Available at 4 distributors Distributor availability of ST1S12G12R
Distributor reported inventory date: 3/3/2025 | | | | Buy from Distributor | | TSOT23-5L | Tape and Reel | MALAYSIA | EAR99 | NEC | -40 | 125 |
ST1S12G18R Active
Part Number:
ST1S12G18R
Operating Temperature (°C)
Min:
-40
Max:
125
MOUSER
Stock
940Min.Order
1DIGIKEY
Stock
13708Min.Order
1Distributor reported inventory date: 3/3/2025
Stock
Min.Order
ST1S12GR Active
Part Number:
ST1S12GR
Operating Temperature (°C)
Min:
-40
Max:
125
Farnell Element14
Stock
2291Min.Order
1ANGLIA Live
Stock
100Min.Order
1MOUSER
Stock
2939Min.Order
1AVNET
Stock
3000Min.Order
0DIGIKEY
Stock
5909Min.Order
1Distributor reported inventory date: 3/3/2025
Stock
Min.Order
ST1S12G12R Active
Part Number:
ST1S12G12R
Operating Temperature (°C)
Min:
-40
Max:
125
Farnell Element14
Stock
2243Min.Order
1MOUSER
Stock
5456Min.Order
1DIGIKEY
Stock
6609Min.Order
1Newark Element14
Stock
280Min.Order
0Distributor reported inventory date: 3/3/2025
Stock
Min.Order
(*) 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