Analog Devices Inc. AD6140ARSRL

Overview

AD6140ARSRL from Analog Devices is a bandpass sigma-delta (Σ∆) IF subsystem IC designed for high-dynamic-range digital radio receivers. It integrates a variable-gain preamplifier (16–29.5 dB), mixer, AGC detector, 6.144 MHz ECL-input Σ∆ modulator, ECL-to-CMOS clock translator, and LNA bias amplifier - all in a single 20-lead SSOP package operating at 2.7 V with 4.8 mA supply current. It targets FLEX™/ReFLEX™ multimode receiver front-ends.

For engineers reviewing the AD6140ARSRL datasheet, AD6140ARSRL pinout, AD6140ARSRL application, or AD6140ARSRL equivalent, key selection considerations include its 192 kHz center-frequency bandpass modulation, 83 dB dynamic range (6.25 kHz BW), –27 dBm input IP3, 10.5 dB noise figure, and AGC time-constant selectability via logic-controlled charging current (2.8 µA / 50 nA).

Technical Context

The AD6140ARSRL implements a fixed-frequency IF signal chain: it accepts a 49.6 MHz IF input and 49.792/49.408 MHz LO to produce a 192 kHz bandpass Σ∆ bitstream output. Its internal AGC loop adjusts preamplifier gain over 13 dB using a voltage-controlled integrator with externally selectable time constant (fast/slow modes).

It features dual-domain power supplies (AVDD/DVDD), separate analog/digital/translator grounds (AGND/DGND/BUFFER_GND), and a dedicated 1 V reference input for ADC accuracy. The ECL-to-CMOS level shifter converts 6.144 MHz differential ECL clock inputs to single-ended CMOS outputs (D_CLOCK_OUT) while driving 5 pF loads with ±2.5% asymmetry.

Key Specifications

Pinout & Package

AD6140ARSRL is housed in a 20-lead plastic Shrink Small Outline Package (SSOP), RoHS-compliant, with 0.65 mm lead pitch and dimensions 7.50 mm × 5.38 mm × 1.78 mm (max height). Pin 1 identifier located at top-left corner per JEDEC MO-153 standard.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar bandpass IF subsystem applications.

Compared with AD6140ARSRL, AD6141ARSRL shifts center frequency and clock rate - requiring LO and decimation filter redesign; MAX2102ETM+ abandons bandpass Σ∆ entirely, trading noise-shaping advantage for baseband flexibility and higher ADC resolution.

Availability

AD6140ARSRL is available at Aetrix Electronics and suitable for FLEX™/ReFLEX™ receiver modules, multimode paging terminals, and industrial telemetry IF interfaces requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for AD6140ARSRL 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 semiconductor company specializing in high-performance analog, mixed-signal, and digital signal processing technologies for precision instrumentation, communications, and industrial applications.

The AD6140ARSRL belongs to Analog Devices' legacy IF subsystem product line, engineered specifically for licensed-band paging receivers requiring bandpass Σ∆ digitization at 192 kHz with integrated AGC and LNA bias control.

FAQ

What is the primary function of the AD6140ARSRL in a receiver signal chain?

The AD6140ARSRL serves as a complete bandpass sigma-delta IF subsystem, converting a 49.6 MHz IF input into a 6.144 MHz single-bit Σ∆ bitstream centered at 192 kHz. It integrates preamplification, mixing, AGC detection, clock translation, and LNA biasing - enabling high-dynamic-range digitization without external modulator or AGC circuitry. Its fixed-frequency architecture makes AD6140ARSRL ideal for standardized paging receiver platforms like Motorola ReFLEX.

Does the AD6140ARSRL support adjustable center frequency or bandwidth?

No - the AD6140ARSRL is a fixed-frequency device optimized exclusively for a 192 kHz center frequency with 6.25 kHz bandwidth (typical dynamic range measurement). Its Σ∆ modulator, mixer LO injection points (49.792/49.408 MHz), and clock input (6.144 MHz) are co-designed for this specific frequency plan. Deviating from these values degrades noise shaping, dynamic range, and linearity - so AD6140ARSRL does not support user-adjustable center frequency or programmable bandwidth.

How does the AGC circuit in the AD6140ARSRL operate, and what external components does it require?

The AD6140ARSRL AGC uses an internal detector that monitors the Σ∆ modulator input level and controls preamplifier gain over 13 dB. It requires an external capacitor on Pin 13 (AGC_CAPACITOR) - typically 0.1 µF per Motorola ReFLEX implementation - and selects fast (2.8 µA) or slow (50 nA) charging current via Pin 10 (AGC_TC_SELECT). No external op amp or resistive divider is needed; the AD6140ARSRL provides full closed-loop AGC with only one capacitor and logic control.

Can the AD6140ARSRL interface directly with an FPGA for decimation filtering?

Yes - the AD6140ARSRL outputs a CMOS-level 6.144 MHz single-bit Σ∆ bitstream on Pin 6 (Σ∆_DATA_OUT) and a synchronized CMOS clock on Pin 7 (Σ∆_CLOCK_OUT), both compatible with standard FPGA I/O banks. Its deterministic timing, ±2.5% clock asymmetry, and 5 pF load drive capability allow direct connection to Xilinx or Intel FPGA fabric for real-time decimation - eliminating level-shifting or buffering for AD6140ARSRL's digital interface.

Is the AD6140ARSRL still in active production, and what is its temperature rating?

The AD6140ARSRL is marked "OBSOLETE" in its official documentation, but remains available through authorized distributors and Aetrix Electronics for legacy support and long-lifecycle industrial programs. It is rated for the industrial temperature range of –40°C to +85°C and specified at 2.7 V supply, making AD6140ARSRL suitable for deployment in uncontrolled outdoor or factory-floor environments where thermal stability is critical.