Microchip Technology HCS201/SN

The HCS201 generates a 66-bit transmission code word combining a 32-bit hopping portion and a 34-bit fixed portion. The fixed portion contains a 28-bit serial number, four button-code bits and two status bits. Three switch inputs, EEPROM-stored configuration and an optional on-chip step-up controller support compact battery transmitters.

Microchip defines SN as an 8-lead plastic SOIC with a 150-mil body. LCDChip registers 8-SOIC (0.154", 3.90 mm width); confirm the controlled package drawing, land pattern and pin-one orientation before layout.

Layout checks

• Orient the 8-lead SOIC using the controlled pin-one marking.
• Route DATA to the transmitter modulation circuit.
• Use the specified battery and STEP connections if step-up is enabled.

This generic JPG illustrates the package outline, not device pin assignments.

Microchip's HCS201 SOIC pin table identifies 1 S0 (switch input 0), 2 S1 (switch input 1), 3 S2 (switch input 2 / programming clock), 4 VDDB (battery input for step-up control), 5 VSS (ground), 6 DATA (PWM output / programming data), 7 STEP (step-up switch control) and 8 VDD (positive supply). Use the controlled pin diagram and application circuit for electrical implementation.

Consult the Microchip data sheet for timing, programming, electrical conditions and step-up component selection.

Other HCS201 order options differ by temperature grade, package or tape-and-reel delivery. They are not automatically interchangeable in procurement or qualification. A different KEELOQ encoder may also change pin functions, button encoding, timing, step-up circuitry or decoder-learning requirements. Verify the complete order code, PCB and system provisioning before considering a substitute. No unverified internal alternative link is asserted.

Microchip Technology's HCS201 KEELOQ Code Hopping Encoder data sheet, DS41098D, defines the code format, pin table, operating range and product identification system. The ordering page identifies the blank commercial-temperature option and /SN 8-lead SOIC package.

Verify the full HCS201/SN order code, package and lot markings, and traceability records. Production acceptance should confirm programming and synchronized communication with the intended receiver; exterior markings do not establish the internal programmed key.

Use the current Microchip HCS201 data sheet, package drawing and applicable notices for final circuit, programming and receiver approval. Effective replay resistance depends on proper key secrecy, receiver synchronization and end-to-end system design; this summary is not a security certification.