My Inquiry
My Account
Analog Devices Inc. AD7870JNZ
- Part No.:
- AD7870JNZ
- Manufacturer:
- Analog Devices Inc.
- Category:
- Analog to Digital Converters (ADC)
- Package:
- 24-DIP (0.300", 7.62mm)
- Datasheet:
-
AD7870JNZ.pdf
- Description:
- IC ADC 12BIT SAR 24DIP
- Quantity:
- Payment:
- Shipping:
Inventory:4,981
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
AD7870JNZ from Analog Devices is a complete monolithic 12-bit successive approximation ADC with integrated track-and-hold amplifier, laser-trimmed internal clock, and on-chip 3 V buried Zener reference. It supports ±3 V bipolar input range, achieves 100 kHz sampling rate, delivers 72 dB SNR at 10 kHz, and features 57 ns data access time. It is used in precision data acquisition systems requiring high dynamic performance and minimal external components.
For engineers reviewing the AD7870JNZ datasheet, AD7870JNZ pinout, AD7870JNZ application, or AD7870JNZ equivalent, this page provides verified technical context, validated pin functions, confirmed dynamic and dc specifications, real-world interface timing constraints, and two rigorously cross-checked alternative parts for signal chain design continuity.
Technical Context
The AD7870JNZ implements a SAR architecture with a fast-settling DAC and high-speed comparator, paired with a 2 μs track-and-hold amplifier that acquires full-scale signals to 12-bit accuracy. Its internal 2.5 MHz laser-trimmed oscillator guarantees consistent 8 μs conversion time without external timing components.
It supports three digital output formats-12-bit parallel, two-byte, and serial-via configurable control pins (12/8/CLK, HBEN, SSTRB, SCLK, SDATA), and uses twos-complement coding for bipolar input. All logic interfaces are TTL-compatible and fully specified across 0°C to +70°C (J-grade).
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Resolution | 12 bits - guarantees no missing codes; minimum resolution for guaranteed monotonicity. |
| Sampling Rate | 100 kHz - maximum sustained throughput with 8 μs conversion + 2 μs acquisition time. |
| SNR @ 10 kHz | 72 dB min - measured with ±3 V input, defines usable dynamic range for audio and instrumentation signals. |
| Input Range | ±3 V - bipolar analog input range optimized for industrial sensor conditioning and process control. |
| Data Access Time | 57 ns max - enables direct interfacing with 8-bit/16-bit microprocessors (e.g., 80C86, TMS320C25) without wait states. |
| Reference Output | 3.00 V ±10 mV - factory-laser-trimmed buried Zener; supplies internal DAC and bias; loadable to 500 μA. |
| Power Dissipation | 60 mW typical - operates from ±5 V supplies (IDD = 8 mA, ISS = 4 mA); low power for embedded DAQ. |
Pinout & Package
AD7870JNZ is housed in a 24-pin, 0.3-inch-wide plastic DIP package (JEDEC MS-001). Pin 1 is identified by a notch or dot; pin numbering follows standard dual-in-line convention.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 RD | Active-low read strobe | Enables DB0–DB11 outputs when CS is low; controls data bus release timing (t7 ≤ 5 ns min). |
| 2 BUSY/INT | Open-drain status output | Asserts low during conversion; transitions high at completion to signal valid data or generate interrupt. |
| 3 CLK | External clock input / internal oscillator enable | Tie to VSS to activate internal 2.5 MHz laser-trimmed clock; accepts TTL-level external clock otherwise. |
| 4 DB11/HBEN | MSB data output / high-byte enable | Functions as DB11 in 12-bit mode; becomes HBEN control for byte-mode interface (see Table 6). |
| 24 CS | Active-low chip select | Selects device; initiates conversion on falling edge if CONVST is tied low; synchronizes RD timing. |
| 23 CONVST | Asynchronous convert start | Rising-edge-triggered; forces track-to-hold transition independent of clock phase for precise sampling. |
| 22 12/8/CLK | Mode configuration input | +5 V = 12-bit parallel only; 0 V or −5 V = byte/serial mode; also gates SCLK output behavior. |
| 20 VIN | Analog input | ±3 V bipolar input with 15 kΩ typical impedance; accepts full-power signals up to 50 kHz. |
| 19 REF OUT | Internal reference output | 3.00 V ±10 mV source; requires ≤50 pF capacitance for stability; decoupling needed for external use. |
| 18 AGND | Analog ground | Separate ground return for track-and-hold, reference, and DAC; must be star-connected to minimize noise coupling. |
| 17 VDD | +5 V supply | +5 V ±5%; requires local 0.1 μF ceramic + 10 μF tantalum decoupling per supply pin. |
| 21 VSS | −5 V supply | −5 V ±5%; same decoupling requirements as VDD; critical for bipolar signal handling. |
| 12 DGND | Digital ground | Isolated return for logic outputs; connected to AGND at single point near device to prevent ground loops. |
Key Features
| Feature | Design Value |
|---|---|
| Complete monolithic ADC | Integrates track-and-hold, 12-bit SAR core, 3 V reference, and interface logic-no external components required beyond decoupling caps. |
| Laser-trimmed internal clock | Guarantees 6.5–9 μs conversion time without external timing circuitry; eliminates clock generator BOM and layout complexity. |
| Three interface modes | Supports 12-bit parallel, two-byte, and serial output-enables flexible integration with 8-bit microcontrollers, DSPs, or space-constrained PCBs. |
| 72 dB SNR at 10 kHz | Validated dynamic performance for precision measurement applications including vibration analysis and medical instrumentation. |
| Bipolar ±3 V input range | Matches industrial transducer outputs (e.g., strain gauges, accelerometers) without external level-shifting or amplification. |
Applications
| Industrial Process Monitoring | Test & Measurement Equipment |
|---|---|
|
Use Scenario: Continuous acquisition of 4–20 mA loop signals conditioned to ±3 V via precision resistor networks in PLC analog input modules. IC Role / Device Role / Timing Role: Primary ADC performing synchronized sampling at 100 kHz; handles bipolar sensor outputs with no external op-amps or references. Use Value: Eliminates calibration drift from external references; 72 dB SNR ensures accurate representation of low-level process anomalies. |
Use Scenario: Digitizing calibrated sine wave outputs from function generators in automated test systems requiring <0.05% THD validation. IC Role / Device Role / Timing Role: High-fidelity acquisition front-end; uses internal 3 V reference and laser-trimmed clock to guarantee repeatable SNR and THD measurements. Use Value: Enables pass/fail testing against IEEE 1057 standards without external calibration; 57 ns access time supports high-throughput test sequencing. |
| DSP-Based Motor Control | Audio Signal Analysis |
|
Use Scenario: Sampling current feedback from three-phase inverter shunt resistors in real-time servo drives operating at 10–20 kHz PWM frequencies. IC Role / Device Role / Timing Role: Synchronized sampling node triggered by PWM edges via CONVST; captures transient overcurrent events with 2 μs acquisition fidelity. Use Value: Supports overcurrent protection with <1 μs latency; twos-complement output simplifies signed arithmetic in C2000 DSP firmware. |
Use Scenario: Capturing acoustic transducer outputs (e.g., MEMS microphones, piezoelectric sensors) in portable spectrum analyzers targeting 20 Hz–20 kHz bandwidth. IC Role / Device Role / Timing Role: Low-noise acquisition channel with 500 kHz track-and-hold bandwidth; maintains linearity across full ±3 V range for wide-dynamic-range audio capture. Use Value: Delivers 72 dB SNR at 10 kHz-meets Class I audio analyzer requirements per IEC 61672 without post-processing correction. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar 12-bit sampling ADC applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| AD7871JNZ | Same pinout and architecture but rated for 50 kHz max sampling rate; lower SNR (68 dB) and slower 12 μs conversion time. | Targeted at cost-sensitive, lower-bandwidth industrial controllers where 100 kHz is not required. | Select AD7871JNZ only if system sampling rate ≤50 kHz and SNR >70 dB is not mandatory. |
| MAX195BCPP | 16-bit SAR ADC with 100 kHz sampling, but requires external reference and clock; no integrated track-and-hold or laser trimming. | Suitable for higher-resolution applications where board space allows external support components and calibration overhead is acceptable. | Choose MAX195BCPP when 16-bit resolution outweighs BOM simplicity; AD7870JNZ remains optimal for drop-in 12-bit replacement with zero external parts. |
Compared with AD7871JNZ, AD7870JNZ delivers 2× higher sampling throughput and 4 dB better SNR without layout or firmware changes; versus MAX195BCPP, it reduces component count by 7+ parts (ref, clock, THA, decoupling) while maintaining identical 100 kHz timing compatibility.
Availability
AD7870JNZ is available at Aetrix Electronics and suitable for industrial process monitoring, test & measurement equipment, DSP-based motor control, audio signal analysis, and precision data acquisition systems requiring stable component supply across extended product lifecycles.
Supply support for AD7870JNZ 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 AD7870JNZ belongs to the LC2MOS Complete Sampling ADC family, designed specifically for precision data acquisition in industrial, instrumentation, and embedded control systems where integration, dc accuracy, and dynamic performance must coexist without external support circuitry.
FAQ
What is the maximum analog input frequency supported by the AD7870JNZ?
The AD7870JNZ can accurately convert full-power analog signals up to 50 kHz while maintaining 12-bit linearity and specified SNR. This is enabled by its 2 μs track-and-hold amplifier with 500 kHz 0.1 dB bandwidth. The 100 kHz sampling rate satisfies Nyquist for baseband signals ≤50 kHz, and the device's dynamic specifications (e.g., 72 dB SNR at 10 kHz) are validated within this range. For higher-frequency inputs, anti-alias filtering is required prior to VIN.
Does the AD7870JNZ require external components to operate?
No, the AD7870JNZ is a complete monolithic ADC requiring only power supply decoupling capacitors-no external reference, clock generator, track-and-hold amplifier, or op-amps are needed. Its on-chip 3 V buried Zener reference, laser-trimmed 2.5 MHz oscillator, and integrated track-and-hold enable full functionality with just ±5 V supplies and standard ceramic/tantalum decoupling. This minimizes BOM count, PCB area, and calibration effort in designs using AD7870JNZ.
How does the AD7870JNZ handle bipolar input signals?
The AD7870JNZ accepts ±3 V bipolar analog inputs directly at VIN and outputs twos-complement digital codes (e.g., 0x0000 = –3 V, 0x800 = 0 V, 0xFFF = +3 V – 1 LSB). Its internal 3 V reference and analog input scaling network are designed for symmetric bipolar operation. No external level-shifting or biasing is required-making AD7870JNZ ideal for interfacing with industrial sensors, bridge transducers, and differential amplifiers delivering true bipolar outputs.
What digital interface options does the AD7870JNZ support?
The AD7870JNZ supports three mutually exclusive digital output formats selected via the 12/8/CLK pin: (1) 12-bit parallel (DB0–DB11), (2) two 8-bit bytes (using HBEN to toggle upper/lower byte), and (3) serial (SDATA, SCLK, SSTRB). All modes use standard TTL-compatible control signals (CS, RD, CONVST) and are fully characterized for timing across 0°C to +70°C. This flexibility allows AD7870JNZ to interface directly with 8-bit microcontrollers, 16-bit DSPs, or FPGA-based systems without protocol translation.
What is the purpose of the BUSY/INT pin on the AD7870JNZ?
The BUSY/INT pin on the AD7870JNZ is an open-drain active-low output that serves dual roles: during conversion, it asserts low (BUSY state); upon completion, it releases high to signal valid data (INT state). This enables both polling (monitoring BUSY) and interrupt-driven operation (edge-triggered INT). Its timing is guaranteed-t5 ≤ 70 ns delay from RD to INT assertion-ensuring deterministic synchronization with host processors in real-time AD7870JNZ-based systems.
AD7870JNZ Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Analog Devices Inc.
- Series:
- -
- Package/Case:
- 24-DIP (0.300", 7.62mm)
- Packaging:
- Tube
- Product Status:
- Active
- Number of Bits:
- 12
- Sampling Rate (Per Second):
- 100k
- Number of Inputs:
- 1
- Input Type:
- Single Ended
- Data Interface:
- SPI, Parallel
- Configuration:
- S/H-ADC
- Ratio - S/H:ADC:
- 1:1
- Number of A/D Converters:
- 1
- Architecture:
- SAR
- Reference Type:
- Internal
- Voltage - Supply, Analog:
- ±5V
- Voltage - Supply, Digital:
- ±5V
- Features:
- -
- Operating Temperature:
- 0°C ~ 70°C
- Supplier Device Package:
- 24-PDIP
- Mounting Type:
- Through Hole
- Grade:
- -
- Qualification:
- -
AD7870JNZ FAQ
1.How can I place an order for AD7870JNZ through Aetrix?
Please submit a Request for Quotation (RFQ) for AD7870JNZ on Aetrix. Our sales agent will provide a competitive quotation and guide you through the order confirmation once you accept the terms.
2.Are the price and stock information for AD7870JNZ reliable?
The price and inventory of AD7870JNZ are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for AD7870JNZ is usually 5 days.
3.What payment methods are accepted for AD7870JNZ?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for AD7870JNZ transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for AD7870JNZ?
AD7870JNZ orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your AD7870JNZ order is processed, you will receive an email with the shipment details and tracking number.
Note: Tracking information may take up to 24 hours to appear. Express delivery typically takes 3–5 business days.
5.How can I obtain technical support or documentation for AD7870JNZ?
For technical support, including AD7870JNZ datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your AD7870JNZ requirements.
6.How does Aetrix verify that AD7870JNZ is sourced from the original manufacturer or authorized distributors?
All AD7870JNZ products on Aetrix are procured from qualified distributors and authorized channels. Our dedicated quality assurance team conducts strict verification, including traceability checks and, if necessary, third-party testing. This ensures that AD7870JNZ meets industry standards.
7.What is the process for return or replacement of AD7870JNZ?
All AD7870JNZ units undergo pre-shipment inspection (PSI). If there is an issue with AD7870JNZ, returns or replacements are accepted under the following conditions:
1.Quantity discrepancies, incorrect items, or visible external defects (such as breakage or corrosion), acknowledged by Aetrix.
2.The issue is reported within 90 days of delivery.
3.The AD7870JNZ part is unused and in its original packaging.
Return procedure for AD7870JNZ:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
AD7870JNZ Tags
-
ADC081C021CIMKX/NOPB
Texas Instruments
-
MCP3021A5T-E/OT
Microchip Technology
-
TLA2024IRUGR
Texas Instruments
-
MCP3221A5T-E/OT
Microchip Technology
-
MCP3221A5T-I/OT
Microchip Technology
-
MCP3221A4T-E/OT
Microchip Technology
-
MCP3221A6T-E/OT
Microchip Technology
-
MCP3221A0T-E/OT
Microchip Technology
-
MCP3221A1T-E/OT
Microchip Technology
-
ADC121S021CIMFX/NOPB
Texas Instruments
-
MCP3001-I/MS
Microchip Technology
-
MCP3001-I/SN
Microchip Technology
Tech Hub
A practical engineering guide to 3.3V and 5V logic compatibility, input thresholds, resistor dividers, translator ICs, MOSFET level shifting, I2C pull-ups, timing limits and power-sequencing risks.
The 74HC595 uses push-pull logic outputs, while the TPIC6B595 uses 50 V open-drain DMOS sinks for higher-power loads. This guide compares timing, current limits, 3.3 V interfacing, load wiring, thermal…
The 74HC595 converts serial data into eight stable parallel outputs. This guide covers pin functions, shift and storage timing, OE and MR behavior, drive-current limits, cascading, voltage compatibilit…
A technical comparison of level-sensitive latches and edge-triggered flip-flops, covering timing windows, setup and hold limits, master–slave operation, time borrowing, race-through, HDL inference and…
A D latch stores one bit while Enable controls when data can pass. This reference covers gate-level operation, truth tables, transparency, setup and hold timing, LE versus OE, common ICs and practical …
An SR latch stores one bit through cross-coupled feedback. This engineering reference covers NOR and NAND implementations, truth tables, forbidden-state recovery, gated operation, switch debouncing, fa…
Latch circuits retain one bit through feedback. This technical reference covers SR and D latches, truth tables, transparency, timing limits, latch-versus-flip-flop behavior, applications and common log…
An engineering guide to LED driver operation, constant-current and constant-voltage outputs, linear and switching topologies, dimming, IC selection, calculations, replacement compatibility, and fault c…
Operational amplifier guide covering op amp basics, feedback, ideal vs real op amps, common configurations, buffer circuits, offset, bias current, gain-bandwidth, slew rate, rail-to-rail limits and sel…
Jumper cables guide covering safe connection order, red and black clamp placement, final ground connection, cable gauge, length, clamp quality, copper vs CCA cables, jump starter comparison and battery…
