Analog Devices Inc. AD1671KP

Overview

AD1671KP from Analog Devices is a monolithic 12-bit, 1.25 MSPS analog-to-digital converter with integrated sample-and-hold amplifier and 2.5 V voltage reference. It delivers 70 dB SNR at 100 kHz input, guarantees no missing codes over 0°C to +70°C, and supports pin-configurable ±5 V / 0 V to +5 V input ranges. It is used in high-speed data acquisition systems requiring precise dc accuracy and fast settling.

For engineers reviewing the AD1671KP datasheet, AD1671KP pinout, AD1671KP application, or AD1671KP equivalent, key selection criteria include conversion time (800 ns), internal reference stability (±25 ppm/°C gain drift), bipolar/unipolar output format flexibility, and out-of-range flag behavior for signal integrity monitoring in real-time sampling systems.

Technical Context

The AD1671KP employs a subranging flash architecture with digital error correction across four internal conversion stages: two 3-bit flash converters followed by coarse/fine 4-bit flash sections. Its on-chip timing generator synchronizes SHA control, DAC subtraction, and residue amplification without external clocks.

It uses Analog Devices' ABCMOS-1 process-integrating high-speed bipolar circuitry for analog front-end linearity and low-power CMOS for logic-to achieve 570 mW power consumption at 1.25 MSPS. Input range selection (±5 V, 0–5 V, ±2.5 V, 0–2.5 V) is determined by strapping AIN1/AIN2, BPO/UPO, and SHA OUT pins per Figure 2 of the datasheet.

Key Specifications

Pinout & Package

AD1671KP is supplied in a 28-pin plastic leaded chip carrier (P-28A) package with gull-wing leads, compatible with surface-mount reflow assembly. Thermal resistance θ_JA is 50°C/W; maximum junction temperature is +150°C.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AD1671KP, AD9220ARZ trades integration for speed and AD9220ARZ requires external timing and reference infrastructure, while MAX1186ECM+ sacrifices parallel interface simplicity and pin-strappable ranges for size and configurability-making AD1671KP optimal for fixed-function, high-reliability sampling where hardware control and self-contained operation are prioritized.

Availability

AD1671KP is available at Aetrix Electronics and suitable for high-speed data acquisition, digital oscilloscope front-ends, and communications baseband processing requiring stable component supply across extended production cycles.

Supply support for AD1671KP 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 is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, founded in 1965 and headquartered in Wilmington, MA.

The AD1671KP belongs to Analog Devices' high-speed monolithic ADC product line, designed specifically for applications demanding integrated signal conditioning, low-latency conversion, and guaranteed monotonicity without external calibration.

FAQ

What is the maximum sampling rate supported by the AD1671KP?

The AD1671KP supports a maximum throughput rate of 1.25 MSPS, corresponding to a minimum conversion time of 800 ns. This rate is achievable across its full specified temperature range (0°C to +70°C) with proper power supply decoupling and layout per Figure 8 in the datasheet. The AD1671KP does not require external clocking-the internal timing generator synchronizes all conversion phases upon each ENCODE pulse.

Does the AD1671KP require an external voltage reference?

No, the AD1671KP includes a laser-trimmed 2.5 V internal voltage reference with ±25 mV initial tolerance and ±25 ppm/°C gain drift. REF OUT (Pin 21) provides this reference for system-wide use. However, REF IN (Pin 24) accepts an external 2.5 V reference if tighter dc accuracy or lower temperature coefficient is required-enabling flexible system-level calibration strategies without redesigning the AD1671KP interface.

How is the input voltage range selected on the AD1671KP?

The AD1671KP supports four input ranges-±5 V, 0–5 V, ±2.5 V, and 0–2.5 V-selected exclusively by hardware pin strapping. Configuration depends on connections between AIN1 (Pin 22), AIN2 (Pin 23), BPO/UPO (Pin 26), and SHA OUT (Pin 25), as shown in Figure 2 of the datasheet. No register writes or digital commands are involved; the setting is static and determined at power-up based on physical traces or jumpers.

What does the OTR pin indicate on the AD1671KP?

The OTR (Out of Range) pin (Pin 15) is an active-HIGH digital output that asserts when the analog input voltage exceeds the selected full-scale range by ≥½ LSB. It remains HIGH until the input returns within range and a new conversion completes. OTR works independently of the MSB and BIT 1–12 outputs, allowing unambiguous detection of over/under-range conditions even during overflow-critical for safety-critical monitoring and automatic gain control loops in the AD1671KP-based system.

Can the AD1671KP operate with different logic and analog supply voltages?

Yes, the AD1671KP uses separate supply domains: VCC (Pin 28) and VEE (Pin 1) for analog circuitry (+5 V / –5 V), and VLOGIC (Pin 18) for digital I/O (+5 V). VLOGIC may operate from +4.5 V to +5.5 V independent of analog rails, supporting mixed-voltage system designs. Power supply rejection is specified at ±4 LSB for VCC, VLOGIC, and VEE variations-ensuring stable conversion accuracy despite moderate supply ripple or sequencing mismatches in the AD1671KP power delivery network.