Part A
ADS7955QDBTRQ1
STマイクロエレクトロニクス
- Lifecycle
- Active
- Stock
- 7159 個数
- Package
- TSSOP-30
- Series
- データ取得 - アナログ/デジタルコンバータ (ADC)
Replacement verdict
Compatible functional replacement candidate
The ADS7955QDBTRQ1 and ADS7961SDBTRG4 are both automotive-qualified, 12-bit SAR ADCs in a 38-pin TSSOP package with an SPI-compatible serial interface, making them strong functional replacement candidates. The primary distinction is channel count: the ADS7955 provides 8 single-ended channels, while the ADS7961 offers 16 single-ended channels. Designers must confirm that the higher channel count and the associated pin-mux configuration of the ADS7961 are acceptable for the target socket, and verify the exact input configuration and reference settings against the system requirements before committing to a drop-in substitution.
Resolution
High match
Package Type
High match
Interface Type
High match
Channel Count
Validation required
Parts at a glance
Part B
ADS7961SDBTRG4
STマイクロエレクトロニクス
- Lifecycle
- Active
- Stock
- 7627 個数
- Package
- TFSOP-38
- Series
- データ取得 - アナログ/デジタルコンバータ (ADC)
Key differences
Rows are prioritized by design impact. Highlighted values require attention during substitution.
Key electrical and mechanical differences between the two devices
| Parameter | ADS7955QDBTRQ1 | ADS7961SDBTRG4 | Why it matters |
|---|---|---|---|
| Resolution | 10 bit | 8 bit | Resolution determines the smallest analog voltage change the ADC can distinguish; a 10-bit device provides four times finer quantization than an 8-bit device, directly affecting measurement accuracy. |
| Number of Input Channels | 8 single-ended | 16 single-ended | Channel count defines how many analog signals can be monitored; the 16-channel device supports twice as many inputs, which affects system architecture and multiplexing needs. |
| Supply Voltage (Analog) | 2.7 V to 5.25 V | 2.7 V to 5.25 V | The analog supply range determines compatibility with the system's voltage rails; identical ranges mean both parts can operate from the same power source. |
| Interface Type | SPI (Serial) | SPI (Serial) | The digital interface must match the host controller; both using SPI allows a common firmware and bus design without rework. |
| Sampling Rate | 1 MSPS | 1 MSPS | Maximum sampling rate sets the bandwidth of signals that can be captured; matching rates means timing performance is equivalent for both parts. |
| Package / Mounting | TSSOP-30 (Surface Mount) | TSSOP-30 (Surface Mount) | Package and footprint must match the PCB layout; identical packages allow drop-in replacement without board redesign. |
| Operating Temperature Range | -40 °C to +125 °C | -40 °C to +125 °C | The temperature range determines suitability for automotive or industrial environments; matching ranges ensure equivalent environmental robustness. |
| Automotive Qualification | AEC-Q100 Qualified | Not AEC-Q100 Qualified | AEC-Q100 qualification indicates the part is validated for automotive reliability; only the Q1 variant is suitable for automotive applications requiring this standard. |
Need help validating a replacement?
Send your BOM and application constraints for technical and sourcing review.
Full specification comparison
Use manufacturer datasheets as the final authority.
| Specification | ADS7955QDBTRQ1 | ADS7961SDBTRG4 |
|---|---|---|
| Supplier | - | Texas Instruments |
| Series | Automotive, AEC-Q100 | microPOWER™ |
| Part Status | Active | Discontinued at Digi-Key |
| Number of Bits | 10 | 8 |
| Sampling Rate(Per Second) | 1M | 1M |
| Number of Inputs | 8 | 16 |
| Input Type | Single Ended | Single Ended |
| Data Interface | SPI | SPI |
| Configuration | MUX-PGA-S/H-ADC | MUX-S/H-ADC |
| Ratio - S / H: ADC | 1:1 | 1:1 |
| Number of A/D Converters | 1 | 1 |
| Architecture | SAR | SAR |
| Reference Type | External | External |
| Voltage - Supply, Analog | 2.7V ~ 5.25V | 2.7V ~ 5.25V |
| Voltage - Supply, Digital | 1.7V ~ 5.25V | 1.7V ~ 5.25V |
| Operating Temperature | -40°C ~ 125°C | -40°C ~ 125°C |
| Features | PGA | - |
Frequently asked questions
What are the key differences between the ADS7955QDBTRQ1 and the ADS7961SDBTRG4?
The ADS7955QDBTRQ1 is an automotive-qualified (AEC-Q100 Grade 1) 10-bit, 8-channel, 1 MSPS SAR ADC in a 30-pin TSSOP (DBT) package, specified over -40°C to +125°C. The ADS7961SDBTRG4 is a 12-bit, 16-channel, 1 MSPS SAR ADC in a 38-pin TSSOP (DBT) package, specified over -40°C to +125°C. The primary differences are resolution (10-bit vs 12-bit), channel count (8 vs 16), package pin count (30 vs 38), and automotive qualification (Q1 vs non-Q1).
Are the ADS7955QDBTRQ1 and ADS7961SDBTRG4 pin-compatible?
No. The ADS7955QDBTRQ1 uses a 30-pin TSSOP package, while the ADS7961SDBTRG4 uses a 38-pin TSSOP package. The different pin counts and pinouts prevent direct PCB footprint compatibility, so a board redesign is required to interchange them.
Do both devices support the same serial interface?
Yes. Both the ADS7955QDBTRQ1 and ADS7961SDBTRG4 use a SPI-compatible serial interface for configuration and data readback, allowing connection to common host controllers and DSPs. However, command framing and channel addressing differ because of the different channel counts, so firmware must be adapted accordingly.
What are the sampling rate and supply requirements for these ADCs?
Both devices are specified for a maximum throughput of 1 MSPS. Both operate from a single analog supply in the 2.7 V to 5.25 V range, with a separate digital I/O supply (VBD) for host interfacing. Designers should confirm exact supply limits and timing in the respective manufacturer datasheets before finalizing the design.
Is the ADS7955QDBTRQ1 automotive qualified while the ADS7961SDBTRG4 is not?
Yes. The ADS7955QDBTRQ1 carries the Q1 suffix indicating AEC-Q100 automotive qualification (Grade 1, -40°C to +125°C), making it suitable for automotive and harsh-environment applications. The ADS7961SDBTRG4 is an industrial-grade device without the Q1 automotive qualification suffix.
Can the ADS7961SDBTRG4 replace the ADS7955QDBTRQ1 in an existing automotive design?
Not directly. Although both are 1 MSPS SAR ADCs, the ADS7961SDBTRG4 is not AEC-Q100 qualified, has a different package (38-pin vs 30-pin TSSOP), and provides 12-bit resolution with 16 channels versus 10-bit with 8 channels. An automotive design requiring Q1 qualification and the existing footprint cannot substitute the non-Q1 part without requalification and PCB redesign.
Which device offers higher resolution and more input channels?
The ADS7961SDBTRG4 offers 12-bit resolution and 16 input channels, whereas the ADS7955QDBTRQ1 offers 10-bit resolution and 8 input channels. The ADS7961SDBTRG4 is therefore better suited to applications needing finer resolution and a larger number of sensor inputs, provided automotive qualification is not required.
What package types do these two ADCs use?
Both devices are offered in TSSOP packages designated by the DBT suffix. The ADS7955QDBTRQ1 is in a 30-pin TSSOP, and the ADS7961SDBTRG4 is in a 38-pin TSSOP. The differing pin counts mean the PCB land patterns are not interchangeable.