Analog Devices Inc. AD7470ARU

Overview

AD7470ARU from Analog Devices is a 10-bit, 1.75 MSPS successive approximation analog-to-digital converter (ADC) with parallel interface, operating from a single 2.7 V to 5.25 V supply. It features 33 pF input capacitance, ±1 LSB integral nonlinearity, and 70 dB typical SNR at 500 kHz - optimized for high-speed data acquisition in industrial instrumentation and real-time control systems.

For engineers reviewing the AD7470ARU datasheet, AD7470ARU pinout, AD7470ARU application, or AD7470ARU equivalent, this page delivers verified specifications, TSSOP-24 package details, timing-critical interface behavior (CONVST-triggered sampling, BUSY-driven read synchronization), and validated alternative options for throughput- and power-sensitive designs.

Technical Context

The AD7470ARU implements a standard successive approximation register (SAR) architecture with no pipeline delay, enabling deterministic conversion timing: 12 clock cycles for conversion plus 135 ns acquisition time. Sampling is edge-controlled via CONVST falling edge, and result availability is signaled by BUSY going low after a fixed 436.42 ns delay (at 30 MHz CLKIN, 5 V).

It uses separate analog (AVDD/AGND) and digital (DVDD/DGND) supplies with strict ≤0.3 V inter-rail tolerance, and supports flexible I/O voltage scaling via VDRIVE (2.7 V–5.25 V) to interface with 3 V or 5 V logic while maintaining analog performance. Reference is externally applied (2.5 V ±1%) to REF IN.

Key Specifications

Pinout & Package

AD7470ARU is housed in a 24-lead Thin Shrink Small Outline Package (TSSOP), RoHS-compliant, with exposed pad not electrically connected. Thermal impedance θ_JA = 115°C/W; recommended solder profile per JEDEC J-STD-020.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 10-bit high-speed ADC applications.

Compared with AD7470BRU, the AD7470ARU trades extended temperature capability for cost and qualification simplicity; compared with AD7472ARU, it delivers 0.25 MSPS higher throughput and ~30% lower power at 3 V, making it optimal for speed- and efficiency-critical 10-bit systems.

Availability

AD7470ARU is available at Aetrix Electronics and suitable for industrial data acquisition, motor control feedback, and portable test equipment requiring stable component supply, long-term obsolescence planning, and traceable sourcing.

Supply support for AD7470ARU 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 AD7470ARU belongs to Analog Devices' precision high-speed SAR ADC product line, designed specifically for applications demanding deterministic timing, low power, and parallel-interface simplicity in industrial and instrumentation systems.

FAQ

What is the maximum clock frequency supported by AD7470ARU?

The AD7470ARU supports a maximum CLKIN frequency of 30 MHz at 5 V supply and 24 MHz at 3 V supply. At 30 MHz, the device achieves its rated 1.75 MSPS throughput, with conversion time fixed at 12 clock cycles. Exceeding these frequencies may cause timing violations or reduced DC accuracy due to insufficient setup/hold margins.

Does AD7470ARU include an internal voltage reference?

No, the AD7470ARU does not include an internal voltage reference. It requires an external 2.5 V ±1% reference applied to the REF IN pin to define the full-scale analog input range (0 V to 2.5 V). The reference input has 10/20 pF capacitance and ±1 µA leakage, so a low-output-impedance reference buffer is recommended for optimal performance.

Can AD7470ARU operate with separate 5 V analog and 3 V digital supplies?

Yes, AD7470ARU supports independent AVDD and DVDD supplies, but they must remain within ±0.3 V of each other at all times - including transients - per absolute maximum ratings. So 5 V AVDD and 3 V DVDD violates this requirement and is not allowed. Valid combinations are 3 V AVDD/DVDD or 5 V AVDD/DVDD, with VDRIVE optionally set to 3 V for 3 V logic interfacing.

How does the auto-sleep mode work on AD7470ARU?

When CONVST remains low after conversion completion, AD7470ARU automatically enters sleep mode on the falling edge of BUSY. In this state, IDD drops to 1 µA max (5 V) or 50 nA typ. A rising edge on CONVST wakes the device in ≤1 µs, after which it is ready for the next conversion. This mode is ideal for burst-mode acquisition with long idle intervals.

Is AD7470ARU pin-compatible with AD7472ARU?

No, AD7470ARU and AD7472ARU are not pin-compatible. While both use TSSOP-24 packages, their pinouts differ: AD7470ARU outputs DB0–DB9 (10 bits) on pins 1–10, whereas AD7472ARU outputs DB0–DB11 (12 bits) on pins 1–12, shifting downstream signals. PCB layout and firmware must be redesigned for substitution.