Analog Devices Inc. AD6402ARS

AD6402ARS integrates a second downconversion mixer, IF bandpass filter, limiting amplifier with RSSI output, PLL demodulator, IF VCO, transmit filter amplifier, mode controls and low-dropout regulator. It targets high-bit-rate FM or FSK TDMA systems around 1 Mbit/s. Receive operation converts an incoming IF signal to a second IF for filtering and demodulation; transmit operation uses the IF VCO and an external varactor tank arrangement for frequency modulation.

The manufacturer's ordering guide specifies AD6402ARS as a 28-lead SSOP. The LCDChip database and package registry classify the footprint as 28-SSOP (0.209", 5.30 mm width). Use the manufacturer package drawing and PCB library to confirm lead pitch, dimensions and pin-one orientation.

Layout checks

• Match the 28-lead SSOP land pattern and pin-one marker.
• Place IF, PLL and VCO supply decoupling close to their respective pins.
• Keep the VCO tank and loop-filter nodes short and away from noisy digital traces.
• Review the external SAW filter, reference and varactor networks against the application schematic.

The registered 28-SSOP JPG is missing locally and must be supplied and checked before publication.

These assignments follow the 28-lead AD6402 pin-function table in the manufacturer's data sheet.

Do not infer pin compatibility from the common SSOP package name; verify every net against the current pin table.

Typical figures and specified-condition values are not guaranteed limits unless the source explicitly identifies a limit. Absolute-maximum stress ratings are not operating settings.

The data sheet also lists AD6402ARS-REEL, which denotes a different supply form for the same 28-lead SSOP device; confirm ordering, marking and handling requirements before substitution. A different IF transceiver must be checked for mixer and demodulator architecture, reference/divider behavior, external tank and loop components, supply rails, mode timing, pinout, footprint, temperature range and qualification. No unverified LCDChip internal alternative link is provided.

Analog Devices identifies AD6402 as obsolete on its product page. Its Rev. 0 obsolete data sheet explicitly lists AD6402ARS in the ordering guide and provides the electrical table, application guidance and pin descriptions used here. Obsolete status makes lifecycle and traceability checks especially important for a new design or service procurement.

Verify the full AD6402ARS marking, 28-lead SSOP body, pin-one orientation, handling condition and traceability against manufacturer-controlled records. This description does not establish provenance, date code or condition for an individual unit.

Review the controlled AD6402 data sheet and a current manufacturer package drawing for complete application-circuit and pin-level design. The registered package JPG is missing locally, so visual package verification is incomplete. Do not treat the obsolete part as an automatically interchangeable substitute for another IF IC.