Texas Instruments CAHC1G125QDBVRQ1

Overview

CAHC1G125QDBVRQ1 from Texas Instruments is an automotive-grade single 3-state bus buffer gate with integrated voltage translation, performing Y = A logic in positive polarity. It operates from 2 V to 5.5 V, delivers ±8 mA output drive at 5 V, consumes ≤10 µA ICC, and supports -40°C to +125°C ambient operation for engine control and body electronics applications.

For engineers reviewing the CAHC1G125QDBVRQ1 datasheet, CAHC1G125QDBVRQ1 pinout, CAHC1G125QDBVRQ1 application, or CAHC1G125QDBVRQ1 equivalent, key selection criteria include AEC-Q100 Grade 1 qualification, SOT-23 (DBV) 5-pin package compatibility, 3-state enable timing (TEN/TDIS < 10.5 ns @ 5 V), and CMOS-level voltage translation across 1.8–5 V domains.

Technical Context

This device implements a single non-inverting buffer with active-high output enable (OE) controlling high-impedance state entry/exit. Its CMOS input structure requires fast transitions (<20 ns/V at 5 V) to prevent oscillation, and its balanced 3-state outputs support bidirectional bus isolation in mixed-voltage systems.

The IC integrates clamp diodes on all I/O pins per JESD17 latch-up specification (>250 mA), meets AEC-Q100 HBM Class 2 (±2 kV) and CDM Class C4B (±1 kV), and references output levels directly to VCC-enabling seamless interfacing between 1.8-V, 2.5-V, 3.3-V, and 5-V logic domains without external level shifters.

Key Specifications

Pinout & Package

SOT-23 (DBV) 5-pin package: 2.9 mm × 2.8 mm footprint, 2.9 mm × 1.6 mm body, 1.45 mm height, gull-wing leads, RoHS-compliant matte tin lead finish, MSL Level-1.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74LVC1G125QDBVRQ1, CAHC1G125QDBVRQ1 offers superior noise immunity and wider input voltage tolerance; compared with MC74VHC1G125DTT1G, it provides guaranteed automotive qualification, thermal reliability, and production traceability for safety-critical vehicle systems.

Availability

CAHC1G125QDBVRQ1 is available at Aetrix Electronics and suitable for engine control units, body control modules, and ADAS camera interfaces requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for CAHC1G125QDBVRQ1 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 company delivering analog and embedded processing solutions, with leadership in automotive, industrial, and personal electronics markets.

The SN74AHC1G125-Q1 belongs to TI's automotive-qualified AHC logic family, designed specifically for robust signal buffering and voltage translation in harsh-temperature vehicle subsystems including powertrain, chassis, and infotainment.

FAQ

What is the maximum capacitive load supported by CAHC1G125QDBVRQ1 while meeting all datasheet specifications?

The CAHC1G125QDBVRQ1 is specified to drive up to 50 pF while maintaining full switching performance-including propagation delay, TEN, TDIS, and output voltage levels-as documented in Sections 6.6 and 6.7 of the datasheet. Driving larger loads increases propagation delay and may degrade VOL/VOH margins; for >50 pF, layout optimization or buffer fanout should be evaluated. The CAHC1G125QDBVRQ1 itself exhibits 10 pF typical input capacitance, minimizing upstream loading.

Does CAHC1G125QDBVRQ1 support true bidirectional operation?

No, CAHC1G125QDBVRQ1 is a unidirectional buffer: signal flows only from input A to output Y. Its 3-state output allows disconnection from the bus, but it does not auto-detect direction or support reverse signal flow. For bidirectional applications like I²C or UART level shifting, a dedicated bidirectional translator such as TXS0102 or PCA9306 is required. The CAHC1G125QDBVRQ1 functions strictly as a controlled one-way gate.

Can CAHC1G125QDBVRQ1 be used to translate between 1.8-V and 3.3-V logic domains?

Yes, CAHC1G125QDBVRQ1 supports voltage translation from 1.8-V inputs to 3.3-V outputs when powered at 3.3 V: its CMOS inputs accept VI down to 0 V and up to 5.5 V, and its output VOH/VOL are referenced to VCC. With VCC = 3.3 V, it reliably converts 1.8-V logic highs (≥1.35 V) into 3.3-V-compatible outputs (VOH ≥ 3.15 V). This capability is explicitly confirmed in Section 8.1 and eliminates need for discrete translators in mixed-supply automotive modules using CAHC1G125QDBVRQ1.

What is the recommended bypass capacitor value and placement for CAHC1G125QDBVRQ1?

Texas Instruments recommends a 0.1-µF ceramic capacitor placed physically adjacent to the CAHC1G125QDBVRQ1 VCC and GND pins, with short, low-inductance traces. Layout Figure 11-1 shows optimal placement: capacitor mounted directly between pins 5 (VCC) and 3 (GND), with GND flood fill beneath the device. Parallel use of 0.1-µF and 1-µF capacitors is acceptable to suppress broadband noise. This configuration ensures stable supply during output switching and prevents ground bounce that could affect CAHC1G125QDBVRQ1 timing margins.

Is CAHC1G125QDBVRQ1 pin-compatible with non-automotive variants like SN74AHC1G125DBVR?

Yes, CAHC1G125QDBVRQ1 shares identical pinout, package dimensions (SOT-23 DBV), and electrical behavior with SN74AHC1G125DBVR, differing only in AEC-Q100 qualification, enhanced ESD robustness (HBM ±2 kV vs ±2 kV standard, CDM ±1 kV vs ±0.5 kV), and extended temperature screening. Both use pin 1 (OE), pin 2 (A), pin 3 (GND), pin 4 (Y), pin 5 (VCC). Therefore, CAHC1G125QDBVRQ1 can replace SN74AHC1G125DBVR in automotive designs without PCB changes, provided qualification and reliability requirements are met.