Analog Devices Inc. AD8138ARM-REEL7

Overview

AD8138ARM-REEL7 from Analog Devices is a high-speed, low-distortion differential ADC driver IC designed for single-ended-to-differential signal conversion in precision data acquisition systems. It delivers −94 dBc SFDR at 5 MHz, 320 MHz −3 dB bandwidth (G = +1), and 1150 V/µs slew rate under ±5 V supply, enabling direct drive of high-resolution (10–16-bit) analog-to-digital converters in communication and instrumentation applications.

For engineers reviewing the AD8138ARM-REEL7 datasheet, AD8138ARM-REEL7 pinout, AD8138ARM-REEL7 application, or AD8138ARM-REEL7 equivalent, key selection criteria include differential output balance error (−66 dB), adjustable VOCM input for common-mode level-shifting, fast 4 ns overdrive recovery, and MSOP-8 package compatibility with space-constrained PCB layouts.

Technical Context

The AD8138ARM-REEL7 employs a dual-feedback architecture: one loop controls differential output voltage via external resistors (RG/RF), while a separate internal common-mode feedback loop forces output common-mode voltage to precisely track the VOCM pin voltage (1:1 ratio). This eliminates reliance on external resistor matching for gain accuracy or balance.

Its proprietary XFCB bipolar process enables simultaneous high bandwidth (320 MHz), ultra-low harmonic distortion (−94 dBc HD2 at 5 MHz), and fast settling (16 ns to 0.01%), making it suitable for wideband IF/baseband gain blocks where phase-matched differential signaling is critical to ADC SNR preservation.

Key Specifications

Pinout & Package

AD8138ARM-REEL7 is housed in an 8-lead MSOP package (3 mm × 3 mm, 0.85 mm height), optimized for high-density mixed-signal PCBs and thermal performance (θJA = 145°C/W on 4-layer board).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar differential ADC driver applications.

Compared with THS4561IRGET and LMH5401RTVT, AD8138ARM-REEL7 offers optimal balance of bandwidth, distortion, and VOCM adjustability in a compact MSOP-8 package-making it the preferred choice for space-constrained, high-fidelity baseband and IF signal chains where common-mode level-shifting is required.

Availability

AD8138ARM-REEL7 is available at Aetrix Electronics and suitable for high-speed data acquisition, communications infrastructure, and medical imaging systems requiring stable component supply, consistent parametric performance, and long-term production continuity.

Supply support for AD8138ARM-REEL7 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

Analog Devices, Inc. is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, headquartered in Norwood, MA.

The AD8138 belongs to Analog Devices' precision high-speed amplifier product line, engineered specifically for demanding differential signal conditioning in data converter interfaces, communications infrastructure, and test & measurement equipment.

FAQ

What is the maximum operating temperature range for the AD8138ARM-REEL7?

The AD8138ARM-REEL7 is specified for operation from −40°C to +85°C ambient temperature. Its MSOP-8 package has a thermal resistance (θJA) of 145°C/W on a standard 4-layer PCB, and junction temperature must not exceed 150°C to ensure reliability. Derating curves in the datasheet define safe power dissipation limits across this temperature range.

Can the AD8138ARM-REEL7 operate from a single 3 V supply?

Yes, the AD8138ARM-REEL7 supports single-supply operation from +2.7 V to +11 V. At +3 V, it maintains usable performance: −3 dB bandwidth drops to ~280 MHz, slew rate to ~950 V/µs, and output swing reduces to 2.9 V p-p (single-ended), while retaining full VOCM adjustability and 4 ns overdrive recovery-enabling low-voltage portable instrumentation designs.

How does the VOCM pin function in the AD8138ARM-REEL7?

The VOCM pin on the AD8138ARM-REEL7 sets the DC common-mode voltage of both +OUT and −OUT outputs with 1:1 tracking. Applying 2.5 V to VOCM centers the differential output around 2.5 V, enabling direct interface with single-supply ADCs. The VOCM input has 100 kΩ impedance and 1 V/V gain, with ±70 dB CMRR to reject noise on the VOCM line itself.

What is the recommended layout practice for minimizing distortion in AD8138ARM-REEL7 circuits?

To minimize distortion, place 0.1 µF ceramic decoupling capacitors within 2 mm of both V+ and V− pins, use symmetric 50 Ω microstrip traces for differential outputs, avoid vias in signal paths, and route VOCM away from noisy digital lines. Ground plane integrity under the MSOP-8 body is critical-thermal pads must be solidly connected to inner ground planes using ≥4 thermal vias.

Does the AD8138ARM-REEL7 require external gain-setting resistors?

Yes, the AD8138ARM-REEL7 uses external resistors (RG and RF) to set closed-loop differential gain per the formula G = 1 + RF/RG. Standard configurations use matched 499 Ω resistors for G = +1. The internal common-mode feedback loop remains active regardless of gain setting, preserving VOCM tracking accuracy and output balance across all gains.