TPS7A78
120-mA, smart, capacitance-drop, low-dropout (LDO) linear voltage regulator
TPS7A78
- Non-isolated power solution for ≥ 18 VAC RMS:
- Up to 75% efficiency
- Standby power consumption: 15 mW (typical)
- Line-voltage, cap-drop capacitor as small as 1/4th the size of linear solutions
- Available in fixed output voltages:
- 1.3 V to 5 V (50-mV steps)
- Power-fail detection
- Power-good indication
- 1% typical accuracy
- Package:
- 5-mm × 6.5-mm HTSSOP-14 (PWP)
The TPS7A78 improves the overall efficiency and standby-power in power-supplies in an easy-to-use, non-magnetic approach to AC/DC conversion. The TPS7A78 uses a capacitor-drop architecture to lower the AC source voltage before actively clamping the rectified voltage. The device then regulates this rectified voltage down to the application-specific operating voltage. The unique architecture of the device allows the standby power to be reduced to just a few 10s of milliwatts. The TPS7A78 switched-capacitor stage reduces power losses by stepping down the rectified input voltage by a factor of four and increasing the output-to-input current by the same ratio, as given by PIN ≅ POUT and VIN ≅ VOUT × 4. Compared to a traditional capacitor-drop (cap-drop) stage, this step down reduces input current, thus minimizing the value of the capacitance needed.
Electricity-metering applications, where the power supply must be reliable and magnetic tamper-proof, benefits from using the TPS7A78 because this device does not require external magnetics. This feature makes complying with IEC 61000-4-8 easier while minimizing magnetic shielding cost.
Additionally, the TPS7A78 also comes with a user-programmable, power-fail detection threshold that can provide an early alert to power failures and enable shutdown before complete power loss. The power-good indicator (PG) is also provided for sequencing or resetting a microcontroller.
The TPS7A78 is available in a 14-pin HTSSOP (PWP) package.
Technical documentation
Type | Title | Date | ||
---|---|---|---|---|
* | Data sheet | TPS7A78 120-mA, Smart AC/DC Linear Voltage Regulator datasheet (Rev. A) | PDF | HTML | 17 Sep 2019 |
EVM User's guide | TPS7A78EVM-041 Evaluation Module User's Guide | PDF | HTML | 16 Aug 2023 | |
Application note | How to Make a Simple Nonmagnetic AC/DC Power Supply | 21 Feb 2020 | ||
White paper | How to detect and harden a meter against tampering by neutral disconnection | 12 Feb 2020 | ||
Technical article | Understanding the difference between capacitors, capacitance and capacitive drop p | PDF | HTML | 10 Sep 2019 | |
EVM User's guide | TPS7A78EVM-011 evaluation module user's guide | 12 Mar 2019 | ||
Technical article | Searching for the newest innovations in power? Find them at APEC | PDF | HTML | 09 Feb 2019 |
Design & development
For additional terms or required resources, click any title below to view the detail page where available.
TPS7A78EVM-011 — TPS7A78 evaluation module for 120-mA, smart, capacitance-drop, LDO linear voltage regulator
The TPS7A78EVM-011 evaluation module (EVM) is designed for a typical configuration to evaluate the operation and performance of the TPS7A78, which is a 120-mA smart AC/DC low-dropout (LDO) linear voltage regulator.
The TPS7A78EVM-011 circuit board is configured to be a reference design for (...)
TPS7A78EVM-041 — TPS7A78 evaluation module for 120-mA smart AC/DC low-dropout linear voltage regulator
The TPS7A78 evaluation module (EVM) evaluates the operation and performance of the TPS7A78 AC/DC linear regulator. This EVM configuration contains a single low standby power, variable output voltage, linear regulator for a wide range of applications. The regulator is capable of delivering up to 120 (...)
TIDA-010036 — One-phase shunt electricity meter reference design using standalone ADCs
TIDA-010060 — Off-line (non-isolated) AC/DC power supply architectures reference design for grid applications
- Off-line switcher using inductor
- AC line (...)
Package | Pins | CAD symbols, footprints & 3D models |
---|---|---|
HTSSOP (PWP) | 14 | Ultra Librarian |
Ordering & quality
- RoHS
- REACH
- Device marking
- Lead finish/Ball material
- MSL rating/Peak reflow
- MTBF/FIT estimates
- Material content
- Qualification summary
- Ongoing reliability monitoring
- Fab location
- Assembly location
Recommended products may have parameters, evaluation modules or reference designs related to this TI product.
Support & training
TI E2E™ forums with technical support from TI engineers
Content is provided "as is" by TI and community contributors and does not constitute TI specifications. See terms of use.
If you have questions about quality, packaging or ordering TI products, see TI support.