MN15261PDU Integrated Circuit

It is a mask-ROM microcontroller from the MN1526x family, used as an encoder for Panasonic/Technics infrared remote controls; detailed documentation (exact pinout, currents, timing) was typically reserved and is no longer distributed today.

Typical family data (indicative, not guaranteed for the specific part number “MN15261PDU”):

• Function: 4-bit MCU with masked ROM and small RAM; key matrix scanning; IR carrier generation; watchdog/timer.
• Protocol: Panasonic IR (carrier ~37.9 kHz; proprietary encoded frames).
• Power supply: 2.0–3.3 V (nominal 3 V from 2×AA/AAA or CR2032).
• Clock: ceramic resonator 455 kHz (sometimes 32.768 kHz); internal division to achieve ~36–40 kHz.
• Current: standby in µA; during transmission some mA in the core; the IR LED is typically driven via an external transistor (peaks of tens of mA on the LED).
• I/O: typical key matrix 4×5 / 5×5 (varies by model); 1 modulated IR output; possible lines for status LEDs.
• Package: DIP/SOP with ~18–24 pins; the suffix “PDU” likely indicates a plastic DIP package (to be confirmed).
• Operating temperature: typ. 0…+70 °C (consumer).