Texas Instruments' UCC28056 device drives PFC boost stages based on an innovative mixed-mode method that operates in transition mode (TM) at full load and transitions seamlessly into discontinuous conduction mode (DCM) at reduced load, automatically reducing switching frequency. This device incorporates burst mode operation to further improve light load performance, enabling systems to meet challenging energy standards while eliminating the need to switch off the PFC. UCC28056 can drive a PFC power stage up to 300 W, ensuring sinusoidal line input current with low distortion, close to unity power factor while keeping the PFC ‘always on’. When used with the LLC controller UCC256301, this 6-pin device eliminates the need for an auxiliary fly back converter, (typically needed in systems for good standby performance) while achieving less than 80 mW at 230 VAC. The device also enables instant turn on while keeping the external component count to a minimum.
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- Low input current distortion and near unity power factor down to 10% load
- Enables compliance to IEC1000-3-2
- Ultra-low no-load input power (25 mW at 115 VAC, 40 mW at 230 VAC)
- Excellent efficiency over the Range of Load
- Enables <60 mW standby power at 115 VAC and <80 mW standby power at 230 VAC in PFC+LLC system
- Enables compliance with green power standards without disabling PFC
- EuP Lot 6 Tier 2, CoC Ver. 5 Tier 2, Energy Star for computers Ver. 6.1, DOE Level VI
- Ultra-low audible noise output
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- Enhanced EA, responds rapidly to load steps without degrading input current distortion
- Burst mode with soft-entry and soft-exit periods
- Valley synchronized turn-on requires no second winding on the boost inductor
- User adjustable valley delay
- Low start-up current consumption (<46 µA)
- Wide VCC range 8.5 V to 34 V
- Cycle-by-cycle current limit
- Second independent output voltage protection
- Integrated over-temperature protection
- Create a custom design using the UCC28056 device with the WEBENCH® Power Designer
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| Applications |
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- Desktop computing/digital TVs
- Gaming/set-top boxes/AC adapters front end
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- LED drivers and luminaries
- Entry-level servers and web servers
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