My Inquiry
My Account
Analog Devices Inc. AD7997BRU-0
- Part No.:
- AD7997BRU-0
- Manufacturer:
- Analog Devices Inc.
- Category:
- Analog to Digital Converters (ADC)
- Package:
- 20-TSSOP (0.173", 4.40mm Width)
- Datasheet:
-
AD7997BRU-0.pdf
- Description:
- IC ADC 10BIT SAR 20TSSOP
- Quantity:
- Payment:
- Shipping:
Inventory:2,295
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
AD7997BRU-0 from Analog Devices is a 10-bit, 8-channel successive approximation ADC with I²C-compatible serial interface, 2 µs conversion time, 2.7 V to 5.5 V supply range, and −40°C to +85°C operating temperature. It integrates an 8:1 analog multiplexer, track-and-hold amplifier, and out-of-range alert function for industrial sensor monitoring systems.
For engineers reviewing the AD7997BRU-0 datasheet, AD7997BRU-0 pinout, AD7997BRU-0 application, or AD7997BRU-0 equivalent, key selection criteria include I²C address configurability via AS pin, 1 µA shutdown current, 188 kSPS maximum throughput in Mode 2 at 5 V, and support for external reference from 1.2 V to VDD - critical for precision multi-sensor data acquisition in space-constrained embedded designs.
Technical Context
The AD7997BRU-0 implements a successive approximation register (SAR) architecture with integrated 8-channel analog multiplexer and track-and-hold, enabling single-supply operation and full-scale input bandwidth up to 11 MHz. Its I²C interface supports standard (100 kHz) and fast (400 kHz) modes only - unlike the -1 variant - and uses pin-selectable addressing (AGND/VDD/floating) to allow up to five devices on one bus.
Conversion control is configurable across three modes: CONVST-triggered (Mode 1), command-mode writes (Mode 2), or automatic cycle interval (Mode 3). The ALERT/BUSY pin serves dual function - as open-drain out-of-range indicator (programmable high/low limits per channel) or BUSY status flag - with hysteresis registers for noise immunity.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Resolution | 10 bits - guarantees monotonic transfer function and no missing codes over full temperature range. |
| Conversion Time | 2 µs typical - enables high-speed sampling of transient analog signals without pipeline latency. |
| Supply Voltage Range | 2.7 V to 5.5 V - supports direct interfacing with 3.3 V and 5 V microcontrollers and sensors. |
| I²C Interface Modes | Standard (100 kHz) and Fast (400 kHz) - no high-speed mode; simplifies timing compliance in legacy I²C systems. |
| Shutdown Current | 1 µA maximum at 3 V - minimizes quiescent power in battery-powered or always-on sensor nodes. |
| Analog Input Channels | 8 single-ended inputs (VIN1–VIN8) - eliminates need for external multiplexing in multi-point measurement systems. |
| Reference Input Range | 1.2 V to VDD - allows flexible scaling: e.g., 2.5 V reference for 0–2.5 V sensor outputs or VDD-referenced ratiometric sensing. |
Pinout & Package
AD7997BRU-0 is housed in a 20-lead TSSOP package (RU suffix), 4.4 mm × 6.5 mm body, 0.65 mm pitch, with exposed pad for thermal enhancement. Pin 1 marked by dot; pins 1, 3, 4, 20 are AGND; pins 2 and 5 are VDD; pin 17 is dual-function ALERT/BUSY; pin 15 is AS for I²C address selection.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1, 3, 4, 20 | AGND | Analog ground reference for all internal circuitry; must be connected to low-impedance system analog ground plane. |
| 2, 5 | VDD | Main power supply input; decoupling capacitor required close to pin for noise suppression during conversion. |
| 6 | REFIN | External voltage reference input; accepts 1.2 V to VDD; requires 0.1 µF + 1 µF bypass capacitors to AGND. |
| 7, 8, 9, 10, 11, 12, 13, 14 | VIN1–VIN8 | Single-ended analog inputs; each accepts 0 V to REFIN; input capacitance 30 pF typical affects anti-alias filter design. |
| 15 | AS | Address select logic input; sets I²C slave address to 0x41, 0x42, or 0x40 depending on AGND/VDD/floating state. |
| 16 | CONVST | Edge-triggered convert start signal; rising edge powers up device; falling edge initiates conversion after ≥1 µs setup. |
| 17 | ALERT/BUSY | Open-drain output; configurable as out-of-range interrupt (per-channel limit violation) or BUSY indicator during conversion. |
| 18 | SDA | I²C bidirectional data line; requires external pull-up resistor; supports standard/fast mode timing only. |
| 19 | SCL | I²C clock input; open-drain compatible; timing compliant up to 400 kHz; no high-speed mode support. |
Key Features
| Feature | Design Value |
|---|---|
| Sequencer operation | Automatically cycles through selected input channels without host intervention - reduces firmware overhead in multi-channel polling. |
| Out-of-range alert with hysteresis | Programmable high/low limit registers per channel plus hysteresis register prevent false triggers from noise near threshold boundaries. |
| Automatic shutdown between conversions | Consumes ≤1 µA in shutdown; powers up only during conversion - extends battery life in intermittent-sampling applications. |
| Pin-selectable I²C addressing | Three unique addresses (0x40, 0x41, 0x42) via AS pin state - enables daisy-chaining up to five AD7997BRU-0 devices on same I²C bus. |
| 2 µs conversion with 11 MHz full-power bandwidth | Supports accurate digitization of fast transients (e.g., motor current spikes, vibration bursts) without aliasing up to 11 MHz. |
Applications
| Industrial Sensor Hub | Smart Energy Metering |
|---|---|
Use Scenario: Simultaneous monitoring of 8 temperature, pressure, and current sensors in a PLC backplane module. IC Role / Device Role / Timing Role: Central 10-bit SAR ADC performing sequenced conversions with I²C readback; ALERT pin flags out-of-spec sensor readings as interrupts. Use Value: Eliminates external multiplexer and level-shifting components; 2 µs conversion enables 188 kSPS aggregate throughput for real-time diagnostics. |
Use Scenario: Multi-phase electricity meter measuring voltage/current across L1/L2/L3/N with auxiliary parameters (temperature, tamper detection). IC Role / Device Role / Timing Role: Precision analog front-end ADC acquiring synchronized samples from shunt/CT circuits; REFIN tied to stable 2.5 V reference for ratiometric accuracy. Use Value: 10-bit resolution and ±0.5 LSB INL ensure Class 0.5 metering compliance; low 1 µA shutdown current supports battery backup during mains failure. |
| Medical Patient Monitor | Automotive Cabin Environment Control |
Use Scenario: Compact wearable vital sign monitor acquiring ECG leads, skin temperature, SpO₂ photodiode outputs, and respiration impedance. IC Role / Device Role / Timing Role: Low-power 8-channel ADC interfaced to ARM Cortex-M0+ MCU via I²C; operates from 3.3 V supply with internal sequencer managing channel order. Use Value: 2.7–5.5 V supply range accommodates coin-cell or USB power; 1 µA shutdown extends runtime between charges; ALERT pin triggers immediate firmware response to abnormal physiological thresholds. |
Use Scenario: HVAC control unit measuring cabin air temperature (4 sensors), humidity, sunlight intensity, and seat occupancy pressure. IC Role / Device Role / Timing Role: Analog acquisition engine converting multiple thermistor, capacitive, and resistive sensor outputs into digital values for PID loop computation. Use Value: Single 20-lead TSSOP replaces discrete ADC + mux solution; I²C address flexibility allows co-location with other I²C peripherals (EEPROM, fan controller); −40°C to +85°C rating ensures reliability in vehicle cabin extremes. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar 8-channel, I²C-compatible ADC applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| AD7997BRU-1 | Supports I²C high-speed mode (3.4 MHz); identical 10-bit resolution, 8-channel, and pinout. | Required when system clock budget demands >400 kHz I²C throughput or lower latency reads. | Select AD7997BRU-1 only if high-speed I²C infrastructure is present; AD7997BRU-0 is optimal for cost-sensitive, legacy I²C designs. |
| AD7992BRU-0 | 2-channel version in same 20-lead TSSOP; shares I²C interface, shutdown mode, and REFIN range but lacks sequencer and ALERT functionality. | Suitable for simpler dual-sensor systems where channel count and alert features are unnecessary. | Choose AD7992BRU-0 when only two analog inputs are needed and board space permits reuse of same footprint with reduced feature set. |
Compared with AD7997BRU-1, the AD7997BRU-0 trades high-speed I²C capability for broader timing margin and lower system complexity; versus AD7992BRU-0, it delivers 4× channel density and integrated alert logic - making it the optimal choice for compact, multi-sensor industrial and medical data loggers requiring deterministic I²C timing and fault detection.
Availability
AD7997BRU-0 is available at Aetrix Electronics and suitable for industrial sensor hubs, smart energy metering, medical patient monitors, and automotive cabin environment control systems requiring stable component supply, long-term lifecycle support, and guaranteed traceable sourcing.
Supply support for AD7997BRU-0 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, with design centers worldwide and ISO 9001-certified manufacturing.
The AD7997/AD7998 product line was designed specifically for space-constrained, low-power, multi-channel data acquisition in industrial automation, building controls, and portable instrumentation - emphasizing integration, I²C simplicity, and robustness across extended temperature ranges.
FAQ
What is the maximum I²C clock frequency supported by the AD7997BRU-0?
The AD7997BRU-0 supports I²C standard mode (100 kHz) and fast mode (400 kHz) only. It does not support high-speed mode (3.4 MHz), which is exclusive to the AD7997BRU-1 variant. This limitation simplifies timing compliance in legacy microcontroller-based systems but caps maximum throughput at 121 kSPS in Mode 1 at 400 kHz SCL. The AD7997BRU-0 datasheet specifies tHIGH ≥ 0.6 µs and tLOW ≥ 1.3 µs under fast mode conditions.
How does the AS pin configure the I²C address of the AD7997BRU-0?
The AS pin on the AD7997BRU-0 selects one of three I²C slave addresses: 0x40 when floating, 0x41 when tied to AGND, and 0x42 when tied to VDD. This pin-driven addressing enables up to five AD7997BRU-0 devices on a single I²C bus without external address jumpers. The configuration is latched at power-up and remains static until reset; no software register write is required to set the address.
Can the AD7997BRU-0 operate with a 1.8 V supply?
No, the AD7997BRU-0 requires a minimum VDD of 2.7 V and is specified for operation from 2.7 V to 5.5 V. A 1.8 V supply falls outside its absolute maximum ratings and will not power the internal reference buffer, SAR core, or I²C interface reliably. For 1.8 V systems, consider the AD7091R-8 (12-bit, 8-channel, SPI interface) or redesign with level-shifting and 3.3 V LDO regulation before the AD7997BRU-0.
What is the purpose of the ALERT/BUSY pin on the AD7997BRU-0?
The ALERT/BUSY pin on the AD7997BRU-0 is a dual-function open-drain output. When configured as ALERT (default), it asserts low when any enabled channel's conversion result exceeds programmable high or low limits stored in DATALOWLIMIT/DATAHIGHLIMIT registers. When configured as BUSY, it goes low during conversion and returns high upon completion. Configuration is controlled via bit 7 of the Configuration Register (0x01).
Does the AD7997BRU-0 require an external reference, and what is its valid voltage range?
Yes, the AD7997BRU-0 requires an external reference applied to the REFIN pin. The valid range is 1.2 V to VDD, allowing ratiometric operation (e.g., REFIN = VDD for sensor bridges) or precision referencing (e.g., REFIN = 2.5 V from REF192). Input impedance is 69 kΩ typical during conversion; 0.1 µF and 1 µF capacitors must be placed between REFIN and AGND to suppress noise and maintain stability.
AD7997BRU-0 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Analog Devices Inc.
- Series:
- -
- Package/Case:
- 20-TSSOP (0.173", 4.40mm Width)
- Packaging:
- Tube
- Product Status:
- Obsolete
- Number of Bits:
- 10
- Sampling Rate (Per Second):
- 188k
- Number of Inputs:
- 8
- Input Type:
- Single Ended
- Data Interface:
- I2C
- Configuration:
- MUX-S/H-ADC
- Ratio - S/H:ADC:
- 1:1
- Number of A/D Converters:
- 1
- Architecture:
- SAR
- Reference Type:
- External
- Voltage - Supply, Analog:
- 2.7V ~ 5.5V
- Voltage - Supply, Digital:
- 2.7V ~ 5.5V
- Features:
- -
- Operating Temperature:
- -40°C ~ 85°C
- Supplier Device Package:
- 20-TSSOP
- Mounting Type:
- Surface Mount
- Grade:
- -
- Qualification:
- -
AD7997BRU-0 FAQ
1.How can I place an order for AD7997BRU-0 through Aetrix?
Please submit a Request for Quotation (RFQ) for AD7997BRU-0 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 AD7997BRU-0 reliable?
The price and inventory of AD7997BRU-0 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for AD7997BRU-0 is usually 5 days.
3.What payment methods are accepted for AD7997BRU-0?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for AD7997BRU-0 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for AD7997BRU-0?
AD7997BRU-0 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your AD7997BRU-0 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 AD7997BRU-0?
For technical support, including AD7997BRU-0 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your AD7997BRU-0 requirements.
6.How does Aetrix verify that AD7997BRU-0 is sourced from the original manufacturer or authorized distributors?
All AD7997BRU-0 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 AD7997BRU-0 meets industry standards.
7.What is the process for return or replacement of AD7997BRU-0?
All AD7997BRU-0 units undergo pre-shipment inspection (PSI). If there is an issue with AD7997BRU-0, 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 AD7997BRU-0 part is unused and in its original packaging.
Return procedure for AD7997BRU-0:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
AD7997BRU-0 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…
