Analog Devices Inc. AD8611ARZ-REEL7

Overview

AD8611ARZ-REEL7 from Analog Devices is a single-channel, ultrafast 4 ns propagation delay comparator with latch function and complementary outputs, operating from 3 V to 5 V single supply. It features 100 MHz input frequency capability, matched rising/falling propagation delays (≤2 ns skew), and rail-to-rail input common-mode range down to GND. It is used in high-speed clock recovery circuits where precise duty-cycle preservation is critical.

For engineers reviewing the AD8611ARZ-REEL7 datasheet, AD8611ARZ-REEL7 pinout, AD8611ARZ-REEL7 application, or AD8611ARZ-REEL7 equivalent, key selection criteria include latch enable timing (0.5 ns setup/hold), input bias current (−7 μA max over temp), output drive capability (3.2 mA sink/source), and compatibility with LT1016/LT1394 PCB layouts for drop-in upgrades in timing-critical systems.

Technical Context

The AD8611ARZ-REEL7 employs a bipolar PNP differential input stage enabling −200 mV to +3.0 V input common-mode range on 5 V supply, with input bias current flowing out of both inputs (−7 μA max at +85°C). Its latch circuit is TTL/CMOS-compatible but nonfunctional below 4.3 V supply.

Propagation delay matching (ΔtP ≤ 2.0 ns) and low input capacitance (3.0 pF) ensure minimal duty-cycle distortion in clock distribution paths. Output stages deliver complementary QA/QA signals with VOH ≥ 2.4 V (IOH = 3.2 mA) and VOL ≤ 0.4 V (IOL = 3.2 mA) at 5 V, supporting direct interfacing to 5 V logic families without level-shifting.

Key Specifications

Pinout & Package

AD8611ARZ-REEL7 is packaged in an 8-lead narrow-body SOIC (R-8) with exposed pad not present. The package meets JEDEC MS-012AC, has θJA = 158°C/W, and is RoHS-compliant.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar high-speed comparator applications.

Compared with LT1394CS8#TRPBF and TLV3501CDR, AD8611ARZ-REEL7 uniquely combines 4 ns speed, latch functionality, and true/complementary outputs in an SOIC-8 package-making it the only option among the three for duty-cycle-preserving clock recovery with event capture capability.

Availability

AD8611ARZ-REEL7 is available at Aetrix Electronics and suitable for high-speed timing, clock distribution, and line receiver applications requiring stable component supply across industrial temperature ranges and long production lifecycles.

Supply support for AD8611ARZ-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 AD8611ARZ-REEL7 belongs to Analog Devices' precision high-speed comparator product line, designed specifically for timing-critical applications including clock recovery, phase detection, and high-speed data acquisition where propagation delay matching and latch capability are essential.

FAQ

What is the minimum supply voltage required for the latch function of AD8611ARZ-REEL7 to operate?

The latch function of AD8611ARZ-REEL7 is not operational below 4.3 V supply voltage. At V+ = 3.0 V, the latch input is unresponsive and must be held low. This behavior is explicitly specified in the datasheet's "LATCH ENABLE INPUT" section and confirmed in Table 2 under "Not functional if VCC < 4.3 V." For designs requiring latch functionality, AD8611ARZ-REEL7 must be operated at ≥4.3 V, typically at 5.0 V nominal.

Can AD8611ARZ-REEL7 be used with a 3.3 V supply, and what are the key trade-offs?

Yes, AD8611ARZ-REEL7 operates from 3.0 V to 5.0 V, so 3.3 V is within specification. However, at 3.3 V, the latch is disabled, input common-mode range shrinks to 0 V to 1.0 V, output swing reduces (VOH ≈ 1.21 V at 3.2 mA), and propagation delay increases to 4.5–6.5 ns. These limitations are documented in Table 2 and the "LATCH ENABLE INPUT" section of the AD8611/AD8612 datasheet Rev. B.

Is AD8611ARZ-REEL7 pin-compatible with LT1016CN8#PBF, and what design changes are needed for replacement?

Yes, AD8611ARZ-REEL7 is pin-for-pin compatible with LT1016CN8#PBF per the datasheet's "UPGRADING THE LT1394 AND LT1016" section. Key design changes include verifying input common-mode voltage stays within 0 V to 3.0 V (vs. LT1016's 1.25 V above GND), confirming latch is not used below 4.3 V, and checking that reduced supply current (5.7 mA vs. 25 mA) does not affect upstream regulators. No PCB layout change is required.

What is the maximum capacitive load AD8611ARZ-REEL7 can drive without exceeding 5 ns propagation delay?

Per Table 7 in the AD8611/AD8612 datasheet Rev. B, AD8611ARZ-REEL7 maintains ≤5 ns propagation delay (rising and falling) only with capacitive loads under 33 pF. At 100 pF, delay increases to 8 ns (rising) and 7 ns (falling). For timing-critical paths, keep total node capacitance-including trace, probe, and load-below 30 pF using short traces and minimal stubs.

Does AD8611ARZ-REEL7 support hysteresis, and how is it implemented?

AD8611ARZ-REEL7 has no internal hysteresis, but external hysteresis can be added via positive feedback (Figure 24 in datasheet). Connect output QA to IN+ through resistor divider R1/R2; hysteresis width is set by R1/(R1+R2) × (V+ − VREF). Capacitor CF adds frequency-dependent hysteresis. This configuration is validated in the "USING HYSTERESIS" section and enables noise immunity in slow-signal, high-noise environments.