Overview
The LM5176PWPT from Texas Instruments is a synchronous four-switch buck-boost DC/DC controller designed to regulate output voltage at, above, or below the input voltage. This controller operates over a wide input voltage range of 4.2 V to 55 V (with an absolute maximum of 60 V) and supports a variety of applications. It uses current-mode control in both buck and boost modes, ensuring superior load and line regulation. The device features integrated 2-A MOSFET gate drivers, programmable soft-start, and various protection mechanisms such as cycle-by-cycle current limiting, input undervoltage lockout (UVLO), output overvoltage protection (OVP), and thermal shutdown.
Key Specifications
| Parameter | Minimum | Typical | Maximum | Unit |
|---|---|---|---|---|
| VIN Range | 4.2 | - | 55 (60 absolute maximum) | V |
| VOUT Range | 0.8 | - | 55 | V |
| Switching Frequency | 100 | - | 600 | kHz |
| Operating Temperature | -40 | - | 125 | °C |
| Package Types | - | - | HTSSOP-28, QFN-28 | - |
| Maximum Junction Temperature | - | - | 150 | °C |
Key Features
- Functional Safety-Capable with available documentation for system design.
- Single inductor buck-boost controller for step-up/step-down DC/DC conversion.
- Wide input voltage range: 4.2 V to 55 V (2.5 V with bias).
- Flexible output voltage range: 0.8 V to 55 V.
- Output short protection and high efficiency buck-boost transition.
- Adjustable switching frequency and optional frequency sync and dithering.
- Integrated 2-A MOSFET gate drivers.
- Cycle-by-cycle current limit and optional hiccup mode protection.
- Optional input or output average current limiting.
- Programmable input UVLO and soft start.
- Power Good and output overvoltage protection.
Applications
- Industrial PC power supplies.
- USB power delivery.
- Battery-powered systems.
- LED lighting.
Q & A
- What is the input voltage range of the LM5176PWPT?
The input voltage range is from 4.2 V to 55 V, with an absolute maximum of 60 V. - What are the output voltage range capabilities of the LM5176PWPT?
The output voltage can be regulated between 0.8 V and 55 V. - What types of packages are available for the LM5176PWPT?
The device is available in HTSSOP-28 and QFN-28 packages. - Does the LM5176PWPT support adjustable switching frequency?
Yes, the switching frequency is adjustable and can be synchronized to an external clock signal. - What protection features are included in the LM5176PWPT?
The device includes cycle-by-cycle current limiting, input undervoltage lockout (UVLO), output overvoltage protection (OVP), and thermal shutdown. - Can the LM5176PWPT be used for battery charging applications?
Yes, it supports optional average input or output current limiting, which is useful for battery charging. - How is the soft-start function programmed in the LM5176PWPT?
The soft-start time is programmed by a capacitor connected to the SS pin. - What is the purpose of the hiccup mode in the LM5176PWPT?
The hiccup mode reduces heating in power components during sustained overload conditions by turning off the controller after a fixed number of switching cycles and restarting after another fixed number of clock cycles. - Is the LM5176PWPT suitable for functional safety applications?
Yes, it is functional safety-capable, with documentation available to aid in system design. - How can I design a custom circuit using the LM5176PWPT?
You can create a custom design using the LM5176 with the WEBENCH Power Designer tool provided by Texas Instruments.
