Rochester Electronics, LLC 74S22SC

Each gate drives its output low when all four inputs are high. An external pull-up is required to produce a high output level. The Fairchild TTL data book identifies the 54S/74S22 as a Schottky TTL dual four-input NAND function with open-collector outputs. Rochester is the cataloged source for this exact order code, but an exact 74S22SC controlled data sheet was not located.

• Two independent four-input NAND functions.
• Open-collector outputs allow an application-selected pull-up.
• Historical 74S Schottky TTL family for legacy board maintenance.
• Single 5 V nominal logic-supply family.
• Four inputs per gate can reduce external gate count.

For each section, a high level on every input turns on the output transistor and produces a low output. If any input is low, the output transistor is off and the external pull-up establishes a high level. Open-collector outputs must not be treated as push-pull CMOS outputs; pull-up value and bus current require circuit-level calculation.

An indexed exact-code distributor description calls 74S22SC a 14-SOIC tube device. The local catalog package is blank, a matching package-registry entry has not been confirmed, and the local 14-SOIC JPG is missing. Confirm lead count, body width, pitch, pin-one orientation and the precise SC suffix with Rochester before PCB layout.

Assembly checks

• Verify exact package outline and land pattern.
• Inspect pin-one marking and supply pins.
• Check tube quantity, finish and lot traceability.

The expected local 14-SOIC JPG is missing.

The 14-pin family drawing shows VCC on pin 14, GND on pin 7, two groups of four logic inputs and their corresponding open-collector outputs. Pins 3 and 11 are marked not connected in the historical family diagram. Confirm the exact Rochester SC pin diagram before layout or substitution.

Family data is not a controlled exact-order specification. Do not assume timing, current or package dimensions without the Rochester documentation.

No database-verified internal replacement is linked. A 74LS22 or 7422 family member may share Boolean behavior but can differ in input loading, output sinking, propagation delay, temperature grade and package. Compare the complete pinout and electrical conditions before substitution.

Rochester Electronics is the listed supplier of the exact catalog code. The original Fairchild TTL data book is primary historical evidence for the 54S/74S22 family function and 14-pin pinout. Neither that family reference nor an indexed distributor snippet proves every specification of the Rochester SC suffix.

• Repair of legacy Schottky TTL logic assemblies.
• Multi-input NAND decoding where an open-collector node is required.
• Shared or wired-logic signaling with a properly sized pull-up.

Check exact markings, lot code, package outline and Rochester traceability. The local catalog currently records 214 units, USD 14.88, minimum quantity 12 and no price tiers. A reseller page repeats the 214-unit figure, while another broker advertises a different quantity and RFQ; these are not a current authorized exact-code price ladder. Preserve catalog pricing until an authorized quote is verified.

Verify pull-up voltage and resistance, sink current, rise time, supply decoupling, input loading, exact-order timing and package outline. Missing local package JPG, unverified registry match, exact SC limits and authorized price tiers prohibit publication.