Texas Instruments SN74LV161284ADGGR

Overview

SN74LV161284ADGGR from Texas Instruments is a 19-bit IEEE 1284-compliant parallel bus interface IC designed for bidirectional asynchronous communication between host and peripheral buses. It features eight A↔B data channels, five cable-side drivers (B1–B8, Y9–Y13, PERI LOGIC OUT), four receivers (C14–C17, HOST LOGIC IN), dual supply operation (VCC and VCC_CABLE), and configurable totem-pole/open-drain output drive via HD pin - enabling compliance with both Level-1 and Level-2 IEEE 1284 standards in printer, scanner, and legacy industrial peripheral interfaces.

For engineers reviewing the SN74LV161284ADGGR datasheet, SN74LV161284ADGGR pinout, SN74LV161284ADGGR application, or SN74LV161284ADGGR equivalent, key selection considerations include dual-supply isolation (VCC/VCC_CABLE), integrated 1.4-kΩ pullups on all open-drain cable-side outputs except HOST LOGIC IN, DIR-controlled directionality, HD-selectable drive mode, and flow-through pin architecture optimized for PCB layout in parallel port bridge designs.

Technical Context

The SN74LV161284ADGGR implements a dual-voltage, directionally controlled bus transceiver with explicit separation of host-side (A-side) and cable-side (B/Y/C-side) signal domains. Its DIR pin selects A→B or B→A data flow, while HD configures output drive mode per IEEE 1284-I/II requirements: HD = low enables open-drain outputs (B, Y, PERI LOGIC OUT) with internal 1.4-kΩ pullups; HD = high enables totem-pole outputs for higher-speed signaling.

It integrates protection features including latch-up immunity >250 mA (JEDEC 17), ESD robustness (4000-V HBM, 300-V MM, 2000-V CDM), and backdrive prevention via PMOS isolation between cable-side I/O and VCC_CABLE. All unused inputs must be tied to VCC or GND per TI SCBA004 guidance to prevent floating CMOS node issues.

Key Specifications

Pinout & Package

TSSOP-48 package (DGG), 12.6 mm × 6.2 mm × 1.2 mm max height, lead-free (NiPdAu), MSL Level-1, RoHS compliant.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar parallel bus interface applications.

Compared with SN74LV161284DLR (SSOP), SN74LV161284ADGGR offers identical functionality in a smaller TSSOP package with tighter pitch but slightly higher thermal resistance; versus SN74ABT16245DGGR, it adds IEEE 1284-specific logic, dual-supply isolation, and integrated pullups - making it irreplaceable for certified parallel peripheral interfacing.

Availability

SN74LV161284ADGGR is available at Aetrix Electronics and suitable for printer interface bridges, industrial scanner controllers, legacy test equipment adapters, and embedded POS peripheral hubs requiring stable component supply across extended production lifecycles.

Supply support for SN74LV161284ADGGR includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Texas Instruments is a global semiconductor leader specializing in analog, embedded processing, and connectivity technologies, with over 50 years of innovation in industrial, automotive, and communications markets.

The SN74LV161284ADGGR belongs to TI's LV family of low-voltage, 5-V tolerant logic interfaces, engineered specifically for robust, standards-compliant parallel peripheral interconnection in industrial and legacy-system upgrade applications.

FAQ

What is the function of the HD pin on the SN74LV161284ADGGR?

The HD (High-Drive) pin on the SN74LV161284ADGGR selects output drive configuration: when HD = high, B, Y, and PERI LOGIC OUT operate in totem-pole mode for IEEE 1284-II compliance; when HD = low, those outputs switch to open-drain mode with integrated 1.4-kΩ pullups for IEEE 1284-I compatibility. This single-pin control eliminates external mode-selection logic and ensures hardware-level standard adherence in the SN74LV161284ADGGR.

Can SN74LV161284ADGGR operate with VCC_CABLE disconnected?

Yes - the SN74LV161284ADGGR safely handles VCC_CABLE = 0 V. When VCC_CABLE is off, PERI LOGIC OUT is forced low, and the PMOS isolation circuit prevents backdrive from cable-side pins into the supply rail. All other cable-side outputs enter high-impedance state, preserving system integrity during hot-plug events. This behavior is explicitly guaranteed in the SN74LV161284ADGGR datasheet under recommended operating conditions.

How does the SN74LV161284ADGGR handle unused inputs?

All unused inputs on the SN74LV161284ADGGR - including DIR, HD, and any unconnected A/B/Y/C pins - must be externally tied to either VCC or GND to prevent floating CMOS nodes, which could cause excessive ICC current, logic instability, or ESD susceptibility. TI's application report SCBA004 mandates this practice, and failure to comply may result in unpredictable operation or accelerated device degradation in the SN74LV161284ADGGR.

What is the purpose of the 1.4-kΩ integrated pullup resistors in the SN74LV161284ADGGR?

The 1.4-kΩ integrated pullup resistors on the SN74LV161284ADGGR are applied to all open-drain cable-side outputs (B1–B8, Y9–Y13, PERI LOGIC OUT) to meet IEEE 1284-I termination requirements without external components. They automatically disable when the associated output is driven low or when VO exceeds VCC_CABLE, preventing contention. This integration reduces BOM count by up to 19 resistors and improves layout density in the SN74LV161284ADGGR design.

Does SN74LV161284ADGGR support hot-swap capability?

Yes - the SN74LV161284ADGGR supports hot-swap operation via dual-supply architecture and PMOS isolation. When VCC_CABLE is powered down while VCC remains active, the device disables cable-side outputs, forces PERI LOGIC OUT low, and blocks backdrive current, allowing safe insertion/removal of parallel cables. This capability is validated per JEDEC 17 latch-up testing (>250 mA) and is a core design feature of the SN74LV161284ADGGR.