TPS7A78

ACTIVE

120-mA, smart, capacitance-drop, low-dropout (LDO) linear voltage regulator

Product details

Output options Fixed Output Iout (max) (A) 0.12 Vin (max) (V) 23 Vin (min) (V) 17 Vout (max) (V) 5 Vout (min) (V) 1.25 Fixed output options (V) 3.3, 3.6, 5 Iq (typ) (mA) 0.28 Thermal resistance θJA (°C/W) 48.0 Rating Catalog Load capacitance (min) (µF) 1 Regulated outputs (#) 1 Features AC/DC regulation, Power good, Power-fail detect Accuracy (%) 2 Operating temperature range (°C) -40 to 125
Output options Fixed Output Iout (max) (A) 0.12 Vin (max) (V) 23 Vin (min) (V) 17 Vout (max) (V) 5 Vout (min) (V) 1.25 Fixed output options (V) 3.3, 3.6, 5 Iq (typ) (mA) 0.28 Thermal resistance θJA (°C/W) 48.0 Rating Catalog Load capacitance (min) (µF) 1 Regulated outputs (#) 1 Features AC/DC regulation, Power good, Power-fail detect Accuracy (%) 2 Operating temperature range (°C) -40 to 125
HTSSOP (PWP) 14 32 mm² 5 x 6.4
  • 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)
  • 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.


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.


Download View video with transcript Video

Technical documentation

star =Top documentation for this product selected by TI
No results found. Please clear your search and try again.
View all 7
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.

Evaluation board

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 (...)

User guide: PDF
Not available on TI.com
Evaluation board

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 (...)

User guide: PDF | HTML
Not available on TI.com
Support software

SBVC046 TPS7A78 Calculator Form

Supported products & hardware

Supported products & hardware

Products
Linear & low-dropout (LDO) regulators
TPS7A78 120-mA, smart, capacitance-drop, low-dropout (LDO) linear voltage regulator
Simulation model

TPS7A78 SIMPLIS 3.3 V Model

SBVM957.ZIP (110 KB) - SIMPLIS Model
Simulation model

TPS7A78 SIMPLIS 3.6 V Model

SBVM958.ZIP (6 KB) - SIMPLIS Model
Simulation model

TPS7A78 SIMPLIS Model (Rev. A)

SBVM947A.ZIP (107 KB) - SIMPLIS Model
Reference designs

TIDA-010036 — One-phase shunt electricity meter reference design using standalone ADCs

This reference design implements Class 0.5 single-phase energy measurement using standalone multi-channel analog-to-digital converters (ADC) to sample a shunt current sensor. With the combination of the shunt sensor and a compact magnetically immune power supply, the design provides protection (...)
Design guide: PDF
Schematic: PDF
Reference designs

TIDA-010060 — Off-line (non-isolated) AC/DC power supply architectures reference design for grid applications

This reference design showcases three non-isolated AC/DC power supply topologies for line-powered applications such as residential circuit interrupters, circuit breakers, home automation equipment and appliances for < 100 mA. The three topologies are:
  • Off-line switcher using inductor
  • AC line (...)
Design guide: PDF
Schematic: PDF
Package Pins Download
HTSSOP (PWP) 14 View options

Ordering & quality

Information included:
  • RoHS
  • REACH
  • Device marking
  • Lead finish/Ball material
  • MSL rating/Peak reflow
  • MTBF/FIT estimates
  • Material content
  • Qualification summary
  • Ongoing reliability monitoring
Information included:
  • 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. ​​​​​​​​​​​​​​

Videos