The PIC16F1769 is the 20-pin flagship of the 176x family: 14 KB of flash, 1024 bytes of SRAM, and the doubled power-supply analogue set – two op amps, four high-speed comparators, a twelve-channel 10-bit ADC, dual 5-bit and 10-bit DACs, and two complementary output generators. Fourteen kilobytes is where this generation starts carrying full lighting engines, and Microchip’s own dimming reference design strings the 10- and 16-bit PWMs, a data signal modulator and a tri-state op amp together into exactly that. When protection is engaged, our decrypt protected PIC16F1769 software service recovers it from hardware you own.

The dimming engine is register choreography

A lighting engine built from this peripheral set is not code so much as choreography: PWM periods, DSM carrier selection, op-amp gain stages and comparator trip points are all configured at boot from constants in flash, and the visible behaviour of a lamp or ballast is their combined output. A clone verified only by checksum therefore says nothing about whether the engine still plays the same tune. Our decrypt protected PIC16F1769 software verification drives the recovered image through dimming steps and load transients on a bench fixture, comparing PWM edges and analogue responses against the donor in real time. That test has caught mis-ordered DSM constants and swapped op-amp gain stages that would have shipped as flicker complaints. Protection on this die is the family’s configuration-word scheme: engaged, external reads are refused; the documented escape is a bulk erase that destroys the array, so it never runs in our procedure. The internal-memory reasoning is in the microcontroller internal storage structure analysis reference, and the legal boundary in the semiconductor chip hardware security overview.

Ramp tables and dimming curves interact in ways that single-point checks miss. A lamp driven by the clone can track the donor perfectly at full and minimum output and still diverge in the middle of the curve, where the PRG slope and the 16-bit PWM resolution trade dominance. Our dimming comparison therefore samples the whole travel – typically eleven setpoints – rather than the endpoints, and the delivery includes the sampled curve so an engineer can see the agreement rather than trust it. The same approach has since been adopted for several motor-control recoveries on the wider family.

Migration into this part from the 171x generation is a recurring request, because pin-compatible layouts invite it. The peripheral sets overlap but do not coincide – register addresses and configuration-word layouts differ – so a heximal cannot simply be moved across; what moves is the design intent. For customers consolidating an old 171x board onto the 1769 we provide both images with a feature-by-feature comparison of the peripheral configuration, which gives their engineers a checklist for the port rather than a blank page.

Duplication and delivery

Verified images go into matching 20-pin blanks with configuration words restored, through the MCU flash EEPROM data cloning pipeline with read-back comparison on every unit. Larger analysis tasks are framed in the MCU reverse engineering concept article.

Perceived brightness is logarithmic, and lighting firmware on this part typically compensates with a gamma or correction table between the commanded level and the PWM compare value. Those tables are dense – one entry per step or per few steps – and a single corrupted entry shows as one visible flat spot in the dimming travel. Our curve sampling is therefore dense enough to catch single-entry errors, and the delivery includes the extracted table so an engineer can verify it against the product’s claimed dimming resolution rather than eyeballing a lamp.

Family links

The 14-pin members are on the PIC16F1764 program and PIC16F1765 code pages, the 7 KB 20-pin sibling on the PIC16F1768 memory recovery, and the 177x 28-pin tier on the PIC16F1773 binary page.

PWM frequency selection interacts with audible noise and efficiency in ways the constants encode silently; two units differing only in a frequency word can sound and run differently under the same load. Frequency is therefore one of the compared parameters in our dimming verification, reported alongside the curve.

Scope

Only devices you own or are authorised to service are accepted, with records kept per job. Send the locked PIC16F1769 and we will confirm the package, quote a fixed fee, and return verified software with its dimming-engine notes.