LM5168PEVM EVM User's Guide
1 LM5168PEVM EVM User Guide
The LM5168PEVM is a 115-V DC/DC buck regulator that employs synchronous rectification to achieve high conversion efficiency in a small footprint. The EVM operates over a wide input voltage range of 20 V to 115 V (120-V absolute maximum) to provide a regulated 12-V output at up to 0.3 A with a 500-kHz switching frequency. The output voltage has better than 1.5% set-point accuracy and is adjustable using an external resistor divider. The module design uses the LM5168P synchronous buck converter with wide input voltage range, wide duty-cycle range, integrated high-side and low-side power MOSFETs, advanced over-current protection, and precision enable. The LM5168P is rated to operate over a junction temperature range of –40°C to +150°C.
| EVM | CONVERTER IC | PACKAGE |
|---|---|---|
| LM5168PEVM | LM5168P | 8-pin SO package with PowerPAD™ integrated circuit package (4.89 mm × 3.90 mm) |
Trademarks
PowerPAD™ is a trademark of Texas Instruments.
All trademarks are the property of their respective owners.
1 General TI High Voltage Evaluation User Safety Guidelines
Always follow TI’s set-up and application instructions, including use of all interface components within their recommended electrical rated voltage and power limits. Always use electrical safety precautions to help ensure your personal safety and the safety of those working around you. Contact TI’s Product Information Center http://support.ti.com for further information.
Save all warnings and instructions for future reference.
Failure to follow warnings and instructions may result in personal injury, property damage, or death due to electrical shock and/or burn hazards.
The term TI HV EVM refers to an electronic device typically provided as an open-framed, unenclosed printed-circuit board assembly. It is intended strictly for use in development laboratory environments, solely for qualified professional users having training, expertise, and knowledge of electrical safety risks in development and application of high-voltage electrical circuits. Any other use and/or application are strictly prohibited by Texas Instruments. If you are not suitably qualified, you should immediately stop from further use of the HV EVM.
- Work Area Safety:
- Maintain a clean and orderly work area.
- A qualified observer or observers must be present any time circuits are energized.
- Effective barriers and signage must be present in the area where the TI HV EVM and its interface electronics are energized, indicating operation of accessible high voltages can be present, for the purpose of protecting inadvertent access.
- All interface circuits, power supplies, evaluation modules, instruments, meters, scopes, and other related apparatus used in a development environment exceeding 50 VRMS/75 VDC must be electrically located within a protected Emergency Power Off (EPO) protected power strip.
- Use a stable and non-conductive work surface.
- Use adequately insulated clamps and wires to attach measurement probes and instruments. No freehand testing whenever possible.
- Electrical Safety:
As a precautionary measure, it is always a good engineering practice to assume that the entire EVM can have fully accessible and active high voltages.
- De-energize the TI HV EVM and all its inputs, outputs, and electrical loads before performing any electrical or other diagnostic measurements. Confirm that TI HV EVM power has been safely de-energized.
- With the EVM confirmed de-energized, proceed with required electrical circuit configurations, wiring, measurement equipment hook-ups, and other application needs, while still assuming the EVM circuit and measuring instruments are electrically live.
- When EVM readiness is complete, energize the EVM as intended.
WARNING:
WARNING: While the EVM is energized, never touch the EVM or its electrical circuits as they could be at high voltages capable of causing electrical shock hazard. - Personal Safety:
- Wear personal protective equipment, for example, latex gloves, safety glasses with side shields, or both, or protect EVM in an adequate lucent plastic box with interlocks from accidental touch.
- Limitation for Safe Use:
- EVMs are not to be used as all or part of a production unit.
Safety and Precautions
The EVM is designed for professionals who have received the appropriate technical training, and is designed to operate from an AC power supply or a high-voltage DC supply. Please read this user's guide and the safety-related documents that come with the EVM package before operating this EVM.
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Do not leave the EVM powered when unattended. | |
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Hot surface! Contact may cause burns. Do not touch! | |
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High Voltage! Electric shock is possible when connecting board to live wire. Board should be handled with care by a professional. For safety, use of isolated test equipment with overvoltage and overcurrent protection is highly recommended. | |
2 EVM Characteristics
Unless otherwise specified, the following conditions apply: TA = 25ºC, VIN = 24 V.
| PARAMETER | TEST CONDITIONS | MIN | TYP | MAX | UNITS | |
|---|---|---|---|---|---|---|
| INPUT CHARACTERISTICS | ||||||
| Input voltage range, VVIN | EVM input voltage operating range | 20 | 48 | 115 | V | |
| Input voltage turn-on, VIN(ON) | Adjusted by EN/UVLO resistors | 6.0 | V | |||
| Input voltage turn-off, VIN(OFF) | 5.6 | V | ||||
| Input voltage hysteresis, VIN(HYS) | 0.4 | V | ||||
| Input current, no load, IIN(NL) | IOUT = 0 A | VIN = 24 V | 29 | μA | ||
| Input current, disabled, IIN(OFF) | VEN/UVLO = 0 V, no EN divider | VIN = 24 V | 4 | µA | ||
| OUTPUT CHARACTERISTICS | ||||||
| Output voltage, VOUT | VIN = 24 V, IOUT = 0A | 12.11 | V | |||
| VIN = 24 V, IOUT = 0.3 A | 12.18 | V | ||||
| Output voltage regulation, ΔVOUT | Load regulation, VIN = 24 V | IOUT = 0 A to 0.05 A | 70 | mV | ||
| Output voltage regulation, ΔVOUT | Load regulation, VIN = 24 V | IOUT = 0.05 A to 0.3 A | 10 | |||
| Output voltage regulation, ΔVOUT | Line regulation, IOUT = 0 A | VIN = 24 V to 115 V | 7 | |||
| Output voltage regulation, ΔVOUT | Line regulation, IOUT = 0.3 A | VIN = 24 V to 115 V | 100 | |||
| Maximum output current | VIN = 24 V | 0.38 | A | |||
| Soft-start time, tSS | 3.5 | ms | ||||
| SYSTEM CHARACTERISTICS | ||||||
| Switching frequency | VIN = 24 V, IOUT1 = 0.3 A | 505 | kHz | |||
| Half-load efficiency | IOUT = 0.15 A | VIN = 24 V | 92% | |||
| Full load efficiency | IOUT = 0.3 A | VIN = 24 V | 93% | |||
| VIN = 60 V | 86% | |||||
3 LM5168PEVM Evaluation Module
The LM5168PEVM is configured to deliver a regulated 12-V output, 0.3 A at 500-kHz switching frequency. The LM5168 uses a COT control architecture, with input voltage feed-forward to provide a constant frequency regulator with tightly regulated output voltage. This type of control requires adequate voltage ripple at the FB input to achieve stable regulation. The LM5168PEVM is set up with type III ripple injection to minimize the output voltage ripple while ensuring a stable regulator. The LM5168PEVM also provides the option to use type I or type II ripple injection. See the LM516x-Q1 0.65/0.3-A, 120-V Step-Down Converter w/ Fly-Buck Converter Capability Data Sheet for more information. Figure 3-1 and Figure 4-1 show an overall view of the LM516PEVM and the schematic, respectively.
