Exact device and ordering identity
UCD3138A64PFCR is an 80-pin PFC package orderable code for the UCD3138A64 digital power controller. This controller is intended for firmware-defined isolated-power regulation and does not contain the external primary-side switching devices or an integrated output regulator. The A64 version and the 128kB family derivative have different firmware-memory implications despite sharing much of the control architecture. For sourcing, retain the A64PFCR identifier rather than replacing it with UCD3138128 or a different pin package.
Alternative Parts — Engineering Review
Source-listed candidate part numbers:
- UCD3138A64PFC
These source-listed candidates are for engineering evaluation only, not confirmed drop-in replacements. Verify voltages, current limits, pinout, footprint, qualification and relevant operating conditions before substitution.
Operating and control considerations
The source family supports independent digital control loops, error A/D conversion and high-resolution digital PWM generation. The up-to-three-loop language describes configurable feedback resources, not three independent power stages included in silicon. TI’s 250ps DPWM pulse-width resolution must not be confused with ADC accuracy, output-voltage regulation error, or PWM output frequency. The exact A64 memory-bank arrangement needs to match the compiled firmware and boot-image strategy, especially if live firmware updates are required.
Package, sourcing and engineering trade-offs
Replacement decisions should compare all 80 PFC pins, control-input topology, communications connections, flash map and startup code before checking packaging and reel quantity. A candidate sharing the UCD3138 name may still require a new board or firmware configuration. Procurement should quote the complete A64PFCR SKU and request assembly details. The listed family candidates are engineering review leads only; the original TI pin-function and package tables govern electrical and mechanical approval.
Manufacturer-verified selection specifications
| Selection parameter | TI-verified value | Engineering condition |
|---|---|---|
| Memory family | 64 kB program flash for this UCD3138A64 orderable (the 128 kB figure belongs to a different family derivative) | Refer to exact manufacturer operating conditions |
| Flash bank | Two 32 kB program-flash banks (64 kB total) | Refer to exact manufacturer operating conditions |
| Control loops | Digital Control of up to 3 Independent Feedback Loops | Refer to exact manufacturer operating conditions |
| Eadc | Up to 16 MSPS Error A/D Converter | Refer to exact manufacturer operating conditions |
| Dpwm | Up to 8 High Resolution Digital Pulse Width Modulated | Output-pin and firmware mapping |
| Pulse width resolution | 250 ps Pulse Width Resolution | Refer to exact manufacturer operating conditions |
| Frequency resolution | 4 ns Frequency and Phase Resolution | Refer to exact manufacturer operating conditions |
| Catalog package | TQFP-80(12×12) | Match exact TI mechanical drawing before footprint or replacement approval |
For an 80-pin PFC controller option with 128 kB of program flash instead of this UCD3138A64's 64 kB, compare UCD3138128APFCR. The A64 and 128A controller variants share digital-power functions but firmware memory, boot resources and peripheral assignments must be checked separately; identical package pin count does not establish drop-in compatibility.
Procurement and datasheet
Request a quotation for UCD3138A64PFCR using the complete orderable number, target quantity and package requirement. Stock, pricing and delivery timing require a direct RFQ confirmation; no on-page availability or price is promised. Source-listed alternative candidates, where present, are for engineering evaluation and do not establish drop-in compatibility.
