Part A
ADS7951SBDBT
Texas Instruments
- Lifecycle
- Active
- Stock
- 5323 PCS
- Package
- TSSOP-30
- Series
- Acquisition de données - Convertisseur analogique - numérique (ADC)
Replacement verdict
Compatible functional replacement candidate
The ADS7951SBDBT and ADS7953SBDBTG4 are both 12-bit, 1-MSPS SAR ADCs from the Texas Instruments ADS795x family, sharing the same TSSOP-38 package, SPI interface, and 2.7 V to 5.25 V supply range. The primary functional divergence is channel count: the ADS7951 provides 8 single-ended inputs, while the ADS7953 provides 16 single-ended inputs (or 8 differential pairs). For designs requiring only 8 channels, the ADS7951SBDBT is a viable functional substitute; designs needing 16 channels must retain the ADS7953SBDBTG4. Pinout and footprint are identical, but channel-count-dependent register configuration and input multiplexer behavior must be validated against the target application.
Channel Count
Validation required
Resolution and Sampling Rate
High match
Package and Pinout
High match
Supply Voltage and Interface
High match
Parts at a glance
Part B
ADS7953SBDBTG4
Texas Instruments
- Lifecycle
- Active
- Stock
- 4855 PCS
- Package
- TFSOP-38
- Series
- Acquisition de données - Convertisseur analogique - numérique (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 | ADS7951SBDBT | ADS7953SBDBTG4 | Why it matters |
|---|---|---|---|
| Number of Input Channels | 8 single-ended | 16 single-ended | Channel count determines how many analog signals can be monitored; a 16-channel part cannot be substituted where 8 channels suffice without layout changes, and vice versa. |
| Resolution | 12 bit | 12 bit | Resolution sets the smallest measurable voltage step; matching 12-bit resolution preserves measurement accuracy and system precision. |
| Sampling Rate | 1 MSPS | 1 MSPS | Maximum throughput must meet the signal bandwidth requirements; identical 1 MSPS rates allow equivalent timing performance. |
| Supply Voltage (Analog) | 2.7 V to 5.25 V | 2.7 V to 5.25 V | Analog supply range must match the system rail; identical ranges ensure the same input signal swing and reference headroom. |
| Interface Type | SPI | SPI | The digital interface must be compatible with the host controller; matching SPI simplifies firmware and hardware reuse. |
| Package | TSSOP-30 | TSSOP-30 | Package footprint and pinout must match for board-level drop-in compatibility; identical TSSOP-30 packages allow the same PCB land pattern. |
| Operating Temperature Range | -40 °C to +125 °C | -40 °C to +125 °C | Temperature range must cover the application environment; identical industrial ranges ensure equivalent reliability. |
| Input Type | Single-ended | Single-ended | Input configuration affects signal conditioning and grounding strategy; both being single-ended means the same front-end design approach applies. |
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Full specification comparison
Use manufacturer datasheets as the final authority.
| Specification | ADS7951SBDBT | ADS7953SBDBTG4 |
|---|---|---|
| Supplier | - | Texas Instruments |
| Series | microPOWER™ | microPOWER™ |
| Part Status | Active | Discontinued at Digi-Key |
| Number of Bits | 12 | 12 |
| Sampling Rate(Per Second) | 1M | 1M |
| Number of Inputs | 8 | 16 |
| Input Type | Single Ended | Single Ended |
| Data Interface | SPI | SPI |
| Configuration | MUX-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 |
Frequently asked questions
What are the key differences between the ADS7951SBDBT and ADS7953SBDBTG4?
The primary difference is channel count and resolution. The ADS7951SBDBT is a 12-bit, 8-channel SAR ADC, while the ADS7953SBDBTG4 is a 12-bit, 16-channel SAR ADC. Both are pin-compatible in the same TSSOP-38 (DBT) package but differ in the number of analog input channels and the corresponding internal multiplexer configuration.
Are the ADS7951SBDBT and ADS7953SBDBTG4 pin-compatible?
Both devices are offered in the same 38-pin TSSOP (DBT) package, but they are not functionally pin-compatible for direct substitution because the analog input channel assignments and multiplexer control differ. The ADS7953SBDBTG4 provides 16 input channels, whereas the ADS7951SBDBT provides 8, so PCB routing and channel mapping must be validated before any replacement.
What is the resolution and sampling rate of these ADCs?
Both the ADS7951SBDBT and ADS7953SBDBTG4 are 12-bit successive-approximation register (SAR) ADCs with a maximum sampling rate of 1 MSPS, as specified in the Texas Instruments ADS795x datasheet.
What is the analog input voltage range and supply requirement?
Both devices operate from a single analog supply (AVDD) of 2.7 V to 5.25 V and a digital supply (DVDD) of 1.7 V to 5.25 V. The analog input range is 0 V to VREF, where VREF is externally supplied and can range from 1.7 V to AVDD, per the ADS795x datasheet.
What serial interface do the ADS7951SBDBT and ADS7953SBDBTG4 use?
Both devices use an SPI-compatible serial interface supporting clock frequencies up to 20 MHz, with a dedicated CS, SCLK, SDI, and SDO. This allows direct connection to most microcontrollers and DSPs without additional glue logic.
Can the ADS7953SBDBTG4 replace the ADS7951SBDBT in an existing design?
Not as a drop-in replacement without design review. Although both share the same package and interface, the ADS7953SBDBTG4 has 16 channels versus 8 on the ADS7951SBDBT, so the multiplexer control words, channel sequencing, and PCB input routing must be revalidated against the target design and the TI datasheet.
What are the operating temperature ranges for these devices?
Both the ADS7951SBDBT and ADS7953SBDBTG4 are specified over the industrial temperature range of -40°C to +125°C, as stated in the Texas Instruments ADS795x datasheet.