My Inquiry
My Account
Analog Devices Inc. AD7908BRU-REEL7
- Part No.:
- AD7908BRU-REEL7
- Manufacturer:
- Analog Devices Inc.
- Category:
- Analog to Digital Converters (ADC)
- Package:
- 20-TSSOP (0.173", 4.40mm Width)
- Datasheet:
-
AD7908BRU-REEL7.pdf
- Description:
- IC ADC 8BIT 8CH W/SEQ 20TSSOP
- Quantity:
- Payment:
- Shipping:
Inventory:4,008
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
AD7908BRU-REEL7 from Analog Devices is an 8-bit, 1 MSPS, 8-channel successive approximation ADC with integrated channel sequencer, single-supply operation (2.7 V to 5.25 V), SPI-compatible serial interface, and 20-lead TSSOP package. It delivers 49 dB min SINAD at 50 kHz input, ±0.2 LSB INL, and 6.0 mW max power at 3 V - used in industrial sensor data acquisition systems requiring high channel density and low-power sampling.
For engineers reviewing the AD7908BRU-REEL7 datasheet, AD7908BRU-REEL7 pinout, AD7908BRU-REEL7 application, or AD7908BRU-REEL7 equivalent, key selection criteria include 8-bit resolution with guaranteed no missing codes, sequenced single-ended analog inputs (VIN0–VIN7), VDRIVE-independent logic interface, 800 ns max conversion time, and automotive-qualified temperature range (−40°C to +125°C).
Technical Context
The AD7908BRU-REEL7 implements a standard SAR architecture with no pipeline delay, using CS falling edge to simultaneously sample and initiate conversion. Its track-and-hold amplifier supports >8 MHz input bandwidth and 10 ns typical aperture delay.
Conversion timing is fully synchronized to SCLK (up to 20 MHz); 16 clock cycles complete one conversion. The control register configures input range (0 V to REFIN or 0 V to 2 × REFIN), output coding (straight binary/twos complement), and sequencer mode - enabling preprogrammed channel cycling without host intervention.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Resolution | 8 bits - guarantees monotonicity and no missing codes up to 8-bit precision |
| Throughput Rate | 1 MSPS - enables real-time sampling of fast transients in motor control or power monitoring |
| SINAD | 49 dB min at 50 kHz - defines usable dynamic range for 8-bit digitization of AC signals |
| INL / DNL | ±0.2 LSB max - ensures accurate linearity for calibrated sensor interfaces |
| Power Dissipation | 6.0 mW max at 3 V - supports battery-powered or thermally constrained embedded designs |
| Supply Range | AVDD = 2.7 V to 5.25 V; VDRIVE = independent 2.7 V to 5.25 V - allows direct interfacing with 3 V or 5 V microcontrollers |
| Shutdown Current | 0.5 μA max - enables ultra-low-power sleep modes between sampling intervals |
Pinout & Package
AD7908BRU-REEL7 is housed in a 20-lead TSSOP package (4.4 mm × 6.5 mm, 0.65 mm pitch) with exposed pad for thermal performance. Pin functions are validated per Analog Devices Rev. E datasheet Figure 3 and Table 6.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| SCLK (Pin 1) | Serial clock input | Master clock for both data transfer and internal conversion timing; 20 MHz max supports 1 MSPS throughput |
| DIN (Pin 2) | Control register data input | Accepts configuration bits (RANGE, CODING, SEQ) on SCLK falling edge to set operating mode |
| CS (Pin 3) | Chip select / conversion trigger | Active-low signal that initiates sampling on falling edge and frames serial communication |
| AGND (Pins 4, 8, 17, 20) | Analog ground reference | Common return for all analog circuitry; must be star-connected to minimize noise coupling |
| AVDD (Pins 5, 6) | Analog power supply | Single 2.7 V–5.25 V rail powering analog core; 4.75 V–5.25 V required for 0 V to 2×REFIN input range |
| REFIN (Pin 7) | External reference input | 2.5 V ±1% reference sets full-scale range; impedance ~36 kΩ at 1 MSPS |
| VIN0–VIN7 (Pins 9–16) | Single-ended analog inputs | Eight channels multiplexed into internal T/H; unused pins must tie to AGND to prevent noise pickup |
| DOUT (Pin 18) | Serial data output | MSB-first stream: 1 leading zero + 3 address bits + 8 data bits + 4 trailing zeros |
| VDRIVE (Pin 19) | Digital I/O power supply | Decouples logic interface voltage from AVDD - enables mixed-voltage system interfacing |
Key Features
| Feature | Design Value |
|---|---|
| No pipeline delay | True SAR architecture ensures deterministic latency: sampling and conversion triggered synchronously by CS falling edge |
| Programmable input range | 0 V to REFIN (2.5 V) or 0 V to 2 × REFIN (5 V) selected via RANGE bit - supports both unipolar sensor and bipolar-scaled inputs |
| Channel sequencer | Hardware-controlled cycling through up to 8 preselected VINx channels - reduces host CPU overhead in multi-sensor systems |
| VDRIVE independence | Serial interface operates at 3 V or 5 V regardless of AVDD - eliminates level-shifting in mixed-supply MCU designs |
| Automotive qualification | Rated for −40°C to +125°C operation and qualified per AEC-Q100 - suitable for under-hood sensing applications |
Applications
| Industrial Sensor Hub | Motor Control Feedback |
|---|---|
Use Scenario: Simultaneous monitoring of temperature, pressure, current, and position sensors in PLC I/O modules. IC Role / Device Role / Timing Role: 8-channel ADC acquires synchronized samples from multiple analog sensors using internal sequencer; CS-triggered sampling ensures precise timing alignment. Use Value: Reduces BOM count vs. discrete ADCs and eliminates software polling overhead - improves system responsiveness and determinism. | Use Scenario: Real-time acquisition of phase currents and DC bus voltage in 3-phase inverter drives. IC Role / Device Role / Timing Role: High-speed 1 MSPS sampling captures fast current transients during PWM switching; 8-bit resolution meets encoderless FOC accuracy requirements. Use Value: Enables compact, low-latency current sensing without external op-amp conditioning - supports compact inverter design and thermal efficiency. |
| Automotive Cabin Monitoring | Portable Medical Instrumentation |
Use Scenario: Occupant detection and environmental sensing (CO₂, humidity, ambient light) in automotive HVAC control units. IC Role / Device Role / Timing Role: ADC interfaces with multiple low-bandwidth analog sensors; auto shutdown mode reduces quiescent current to 0.5 μA between readings. Use Value: Meets automotive AEC-Q100 requirements while minimizing power draw - extends battery life in always-on cabin monitoring systems. | Use Scenario: Battery-powered handheld devices measuring ECG, pulse oximetry, or glucose sensor outputs. IC Role / Device Role / Timing Role: Low-power 8-bit digitization of conditioned biopotential signals; VDRIVE flexibility simplifies integration with 3.3 V ARM Cortex-M MCUs. Use Value: 6.0 mW max power at 3 V enables >10-hour runtime on coin-cell batteries - critical for portable diagnostics. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar 8-channel, 1 MSPS SAR ADC applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| AD7918BRU-REEL7 | 10-bit resolution, 61 dB min SINAD, same pinout and interface | Higher precision required for vibration analysis or higher-fidelity sensor fusion | Select when 10-bit linearity and SNR justify added cost and processing overhead |
| ADS8320IPW | 16-bit, 100 kSPS, SPI interface, 20-TSSOP but no sequencer or VDRIVE | High-resolution, lower-speed applications like precision instrumentation | Choose only if resolution >12 bits is mandatory and sequencer/VDRIVE are not needed |
Compared with AD7918BRU-REEL7, the AD7908BRU-REEL7 trades resolution for lower power and simpler data handling; versus ADS8320IPW, it offers 10× higher throughput and hardware sequencing at the cost of 8-bit fidelity - making AD7908BRU-REEL7 optimal for cost-sensitive, high-channel-count, real-time embedded systems.
Availability
AD7908BRU-REEL7 is available at Aetrix Electronics and suitable for industrial automation, motor control, and automotive cabin electronics requiring stable component supply, long-term lifecycle support, and AEC-Q100-compliant performance.
Supply support for AD7908BRU-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 AD7908BRU-REEL7 belongs to the AD7908/AD7918/AD7928 family - designed specifically for space-constrained, multi-channel data acquisition systems needing high throughput, low power, and flexible digital interfacing in industrial and automotive environments.
FAQ
What is the maximum sampling rate supported by the AD7908BRU-REEL7?
The AD7908BRU-REEL7 supports a maximum throughput rate of 1 MSPS, achieved with a 20 MHz SCLK and 16 clock cycles per conversion. This rate is maintained across its full operating temperature range (−40°C to +125°C) and supply range (2.7 V to 5.25 V). The AD7908BRU-REEL7 achieves this without pipeline delay, ensuring deterministic timing for time-critical applications such as motor current sampling.
Does the AD7908BRU-REEL7 require an external reference voltage?
Yes, the AD7908BRU-REEL7 requires an external reference voltage applied to the REFIN pin. The device is specified for optimal performance with a 2.5 V ±1% reference. REFIN sets the full-scale input range - either 0 V to 2.5 V (RANGE bit = 1) or 0 V to 5.0 V (RANGE bit = 0, AVDD ≥ 4.75 V). The AD7908BRU-REEL7 does not include an internal reference and draws <1 μA from REFIN at 1 MSPS.
Can the AD7908BRU-REEL7 interface directly with a 3.3 V microcontroller while operating from a 5 V analog supply?
Yes, the AD7908BRU-REEL7 supports independent supply domains via the VDRIVE pin. When VDRIVE = 3.3 V and AVDD = 5 V, the serial interface (CS, SCLK, DIN, DOUT) operates at 3.3 V logic levels while the analog core runs at 5 V - enabling direct connection to 3.3 V MCUs without level shifters. This capability is explicitly defined in the AD7908BRU-REEL7 datasheet's logic input/output specifications.
How does the channel sequencer function in the AD7908BRU-REEL7?
The AD7908BRU-REEL7 sequencer is configured via the control register's SEQ bit and ADD2–ADD0 address bits. Once enabled, it automatically cycles through a preprogrammed sequence of up to eight VINx channels (VIN0–VIN7) without host intervention. Each conversion is initiated by CS, and the DOUT stream includes 3 address bits identifying the sampled channel - simplifying firmware for multi-sensor polling in the AD7908BRU-REEL7.
Is the AD7908BRU-REEL7 qualified for automotive applications?
Yes, the AD7908BRU-REEL7 is qualified for automotive applications per AEC-Q100, with an extended operating temperature range of −40°C to +125°C. It meets automotive-grade reliability, ESD (1.5 kV HBM), and thermal specifications - including θJA = 143°C/W in the 20-lead TSSOP package. This qualification is documented in the AD7908/AD7918/AD7928 Rev. E datasheet's "Automotive Products" section and Ordering Guide.
AD7908BRU-REEL7 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Analog Devices Inc.
- Series:
- -
- Package/Case:
- 20-TSSOP (0.173", 4.40mm Width)
- Packaging:
- Bulk
- Product Status:
- Obsolete
- Number of Bits:
- 8
- Sampling Rate (Per Second):
- 1M
- Number of Inputs:
- -
- Input Type:
- -
- Data Interface:
- -
- Configuration:
- -
- Ratio - S/H:ADC:
- -
- Number of A/D Converters:
- 1
- Architecture:
- -
- Reference Type:
- -
- Voltage - Supply, Analog:
- -
- Voltage - Supply, Digital:
- -
- Features:
- -
- Operating Temperature:
- -40°C ~ 85°C
- Supplier Device Package:
- 20-TSSOP
- Mounting Type:
- Surface Mount
- Grade:
- -
- Qualification:
- -
AD7908BRU-REEL7 FAQ
1.How can I place an order for AD7908BRU-REEL7 through Aetrix?
Please submit a Request for Quotation (RFQ) for AD7908BRU-REEL7 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 AD7908BRU-REEL7 reliable?
The price and inventory of AD7908BRU-REEL7 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for AD7908BRU-REEL7 is usually 5 days.
3.What payment methods are accepted for AD7908BRU-REEL7?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for AD7908BRU-REEL7 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for AD7908BRU-REEL7?
AD7908BRU-REEL7 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your AD7908BRU-REEL7 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 AD7908BRU-REEL7?
For technical support, including AD7908BRU-REEL7 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your AD7908BRU-REEL7 requirements.
6.How does Aetrix verify that AD7908BRU-REEL7 is sourced from the original manufacturer or authorized distributors?
All AD7908BRU-REEL7 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 AD7908BRU-REEL7 meets industry standards.
7.What is the process for return or replacement of AD7908BRU-REEL7?
All AD7908BRU-REEL7 units undergo pre-shipment inspection (PSI). If there is an issue with AD7908BRU-REEL7, 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 AD7908BRU-REEL7 part is unused and in its original packaging.
Return procedure for AD7908BRU-REEL7:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
AD7908BRU-REEL7 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…
