TNY277PN - 18.5W Flyback Switcher IC | Power Integrations
MPN: TNY277PN ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $1.12 | $1.12 |
| 10 | $1.03 | $10.30 |
| 100 | $0.91 | $91.00 |
| 500 | $0.84 | $420.00 |
| 1,000 | $0.78 | $780.00 |
TNY277PN Overview
An offline switcher is a power-management integrated circuit that accepts rectified AC line voltage and performs high-frequency switching to provide one or more isolated DC outputs through a flyback transformer. The TinySwitch-III family is a subcategory of AC-DC converters, which sit above linear regulators and standard DC-DC converters in the power conversion hierarchy. By integrating the power MOSFET and controller on one chip, offline switcher ICs reduce BOM count, simplify PCB layout, and improve reliability compared to discrete controller-plus-MOSFET implementations.
Key features of the TNY277PN include the built-in 700 V power MOSFET, which provides wide margin for line-voltage spikes and improves surge robustness. The integrated high-voltage switched current source accelerates startup and reduces no-load input power. The user-selectable current limit lets designers optimize transformer size for the target power level, while the 132 kHz switching frequency balances transformer size against switching losses. Thermal shutdown protects the IC against secondary-side overload or fault conditions.
In operation, the IC uses a simple ON/OFF control scheme that requires no external loop compensation. The internal oscillator controls the power MOSFET duty cycle; when output feedback demands energy, the MOSFET switches, then enters a low-power state. This burst-mode operation at light load reduces standby losses and is especially useful for Energy Star-compliant adapters. The through-hole 8-pin DIP package simplifies assembly and helps transfer heat to PCB copper in moderate-power designs.
Typical applications include AC/DC adapters and battery chargers, standby and auxiliary power supplies for appliances, LED drivers, industrial control supplies, and IoT smart-home power modules. The flyback topology pairs with inexpensive transformers and standard optocoupler/TL431 feedback networks.
When designing with TNY277PN, pay attention to drain snubber selection, transformer leakage inductance, and BP/M pin decoupling. A well-laid-out PCB with tight loop areas is critical for meeting conducted EMI limits.
Drop-in alternatives for TNY277PN — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Variants in this series
Same-series models that are drop-in compatible with TNY277PN (same form factor and footprint) — differing in Package.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
TNY276PN
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
TNY277PG
✅ Drop-In✓ In Stock
$0.75 / Unit
View Datasheet →TNY278PN
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
TNY279PN
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
TNY280PN
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
TNY277PN Maximum Ratings & Electrical Characteristics
| Topology | Flyback |
| Switching Frequency | 132 kHz |
| Built-in Power MOSFET | 700 V |
| Max Output Power (85-265 VAC) | 18.5 W |
| Max Output Power (230 VAC) | 23.5 W |
| Package | 8-PDIP-C |
| Mounting Type | Through Hole |
| Control Scheme | ON/OFF |
| Current Limit | User selectable |
| High-Voltage Switched Current Source | Yes |
| Thermal Shutdown | Yes |
| Startup Circuitry | Integrated high-voltage switched current source |
TNY277PN 8-pdip-c Pin Configuration Guide
Pin configuration for TNY277PN (8-pdip-c package). This power device features gate, drain, and source terminals. For non-polarized packages, refer to the manufacturer datasheet for exact pin 1 orientation and footprint details. Common applications include power supply design, motor driving, and load switching.
No detailed pinout data available for TNY277PN.
Refer to the datasheet for full pin configuration.
Typical Applications
TNY277PN is suitable for 6 applications: AC/DC Adapters and Battery Chargers, Standby and Auxiliary Power Supplies, Appliance Power Supplies, LED Power Supplies and Lighting, Industrial Control Power Supplies, IoT and Smart Home Power Modules.
AC/DC Adapters and Battery Chargers
The TNY277PN is suited to 5V/2A and 12V/1.5A AC/DC adapters because its 18.5 W universal-input rating provides headroom for load transients. The integrated 700 V MOSFET reduces external component count, and the 132 kHz oscillator allows a small transformer. In typical flyback adapter designs, optocoupler feedback drives the EN/UV pin and a TL431 is used for output-voltage regulation. This IC simplifies charger production while meeting no-load loss expectations for modern adapters.
Recommended
Standby and Auxiliary Power Supplies
TNY277PN is well suited for standby supplies that must stay energized while the main system is off. Its ON/OFF control enables low standby consumption and the 700 V MOSFET provides robust line-surge tolerance for appliance power boards. As an auxiliary supply, it can generate a clean 12V or 5V rail from the AC line using a simple flyback stage. The built-in current limit and thermal shutdown protect the IC during fault conditions common in appliance environments.
Recommended
Appliance Power Supplies
For washing machines, refrigerators, and stove control boards, TNY277PN provides a cost-effective 18.5W flyback supply for control electronics, relays, and displays. The through-hole 8-PDIP-C package is easy to assemble in conventional appliance PCBs, and the 700 V integrated MOSFET withstands high-voltage AC line transients. Designers can configure the current limit to match the transformer and load. Its thermal shutdown and simple ON/OFF control reduce firmware-side power-sequencing complexity in white-goods applications.
Recommended
LED Power Supplies and Lighting
LED lighting panels and bulbs can use TNY277PN as the core of an isolated offline LED driver. The 18.5W universal input power supports many 15W LED modules, while the 700 V MOSFET and current-limit selection allow the transformer to be optimized for constant-voltage or constant-current output. The IC's low standby power helps meet residential lighting efficiency requirements. Its flyback topology is compatible with secondary-side constant-current feedback circuits using TL431 and current-sense resistors.
Recommended
Industrial Control Power Supplies
In industrial sensors, PLCs, and motor-control panels, TNY277PN supplies clean DC power for microcontrollers and communication interfaces. Its 85-265 VAC universal input makes it suitable for worldwide installations, while the 700 V MOSFET gives extra safety margin against industrial mains transients. The user-selectable current limit can be tuned to the transformer overcurrent protection. Tight load regulation is achievable through standard optocoupler/TL431 feedback, and the 132 kHz frequency keeps the magnetic components compact for DIN-rail or panel-mount form factors.
Recommended
IoT and Smart Home Power Modules
Smart home hubs, Wi-Fi modules, and sensor bridges need compact isolated power supplies. TNY277PN can deliver up to 18.5W universal input, enough to power a main board plus accessories. The integrated 700 V MOSFET and high-voltage current source reduce BOM size, while the low standby power helps smart devices meet energy-use requirements. The flyback converter can be designed with a small E20/E25 transformer and optocoupler feedback to create a reliable 5V rail for IoT processors, wireless transceivers, and sensors.
Recommended
Recommended Products Summary
Engineering reference data for TNY277PN — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | TNY276PN | TNY277PG | TNY278PN | TNY279PN | TNY280PN |
|---|---|---|---|---|---|---|
| Brand | Power Integrations | Power Integrations | Power Integrations | Power Integrations | Power Integrations | Power Integrations |
| Package | 8-PDIP-C | 8-PDIP-C | 8-PDIP-C | 8-PDIP-C | 8-PDIP-C | 8-PDIP-C |
Key Differentiators
- 18.5 W universal input rating provides margin for common 10-15 W adapter designs (vs TNY276PN)
- Balanced power class for cost-sensitive flyback supplies (vs TNY280PN)
- Verified cross-reference visibility of TNY277PG (vs TNY277PG)
Design Notes
Do not leave BP/M pin floating. Connect the recommended BP/M capacitor, typically a 0.1uF ceramic capacitor, close to the IC. This capacitor supplies gate-drive current and sets the internal supply voltage. In TinySwitch-III designs, the BP/M pin can also accept an external current-limit set resistor in some configurations, as described in the Power Integrations datasheet.
The TNY277PN uses an 8-PDIP-C through-hole package that relies on PCB copper and the lead frame for heat removal. For continuous operation near 18.5 W universal input, provide adequate copper area around drain and source leads, preferably on both top and bottom layers. Junction temperature must stay within datasheet limits; if case temperature is high, redesign the transformer or improve air flow rather than increasing copper indefinitely.
Minimize the high-frequency drain loop by placing the transformer primary, rectifier diode, and bulk capacitor close to the drain and source pins. Keep the feedback optocoupler and TL431 sense traces short. Add a Y-capacitor between primary and secondary for common-mode EMI and follow appropriate creepage and clearance distances for the AC input voltage class.
Compliance Information
Verified web snippets did not include explicit RoHS/REACH certification details. Refer to the Power Integrations datasheet and product page for current compliance documentation.
