Part A
ADC121S051CIMF
Texas Instruments
- Lifecycle
- Active
- Stock
- 1513 PCS
- Package
- SOT-23-6
- Series
- Acquisition de données - Convertisseur analogique - numérique (ADC)
Replacement verdict
Compatible functional replacement candidate
The ADC121S101CIMFX is a functional replacement candidate for the ADC121S051CIMF, sharing the same 12-bit SAR architecture, SOT-23-6 footprint, and single-supply operating range, while offering a higher throughput rate of up to 1 MSPS versus 500 kSPS. Designers should validate timing margins and SPI clock compatibility in the target application before substituting, as the faster conversion rate may require adjusted interface timing.
Resolution
High match
Package Type
High match
Supply Voltage Range
High match
Sampling Rate
Validation required
Parts at a glance
Part B
ADC121S101CIMFX
Texas Instruments
- Lifecycle
- Active
- Stock
- 8967 PCS
- Package
- SOT-23-6
- 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 | ADC121S051CIMF | ADC121S101CIMFX | Why it matters |
|---|---|---|---|
| Resolution | 12 bit | 12 bit | Both are 12-bit ADCs, so they provide the same quantization resolution and are interchangeable in terms of measurement precision. |
| Sampling Rate | 200 kSPS | 1 MSPS | The ADC121S101 supports a much higher throughput (1 MSPS vs 200 kSPS), which matters for higher-bandwidth signal acquisition and may not be substitutable in timing-critical designs. |
| Number of Input Channels | 1 single-ended | 1 single-ended | Both provide a single single-ended input channel, so channel count and input configuration are equivalent for substitution. |
| Supply Voltage Range | 2.7 V to 5.25 V | 2.7 V to 5.25 V | Identical supply range means both can operate from the same system rails without level shifting or regulator changes. |
| Interface Type | SPI / QSPI / MICROWIRE compatible serial | SPI / QSPI / MICROWIRE compatible serial | Same serial interface protocol allows drop-in replacement on the digital side without firmware or bus reconfiguration. |
| Package / Mounting | SOT-23-6, surface mount | SOT-23-6, surface mount | Identical package and footprint enable direct PCB substitution without layout changes. |
| Operating Temperature Range | -40 °C to +125 °C | -40 °C to +125 °C | Same industrial temperature range ensures both parts meet the same environmental requirements. |
| Power Consumption (Typical) | Lower due to 200 kSPS throughput | Higher due to 1 MSPS throughput | The faster ADC121S101 typically draws more supply current at full rate, which matters for low-power or thermally constrained designs. |
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Full specification comparison
Use manufacturer datasheets as the final authority.
| Specification | ADC121S051CIMF | ADC121S101CIMFX |
|---|---|---|
| Supplier | - | Texas Instruments |
| Part Status | Obsolete | Obsolete |
| Number of Bits | 12 | 12 |
| Sampling Rate(Per Second) | 500k | 1M |
| Number of Inputs | 1 | 1 |
| Input Type | Single Ended | Single Ended |
| Data Interface | SPI, DSP | SPI, DSP |
| Configuration | S/H-ADC | S/H-ADC |
| Ratio - S / H: ADC | 1:1 | 1:1 |
| Number of A/D Converters | 1 | 1 |
| Architecture | SAR | SAR |
| Reference Type | Supply | Supply |
| Voltage - Supply, Analog | 2.7V ~ 5.25V | 2.7V ~ 5.25V |
| Voltage - Supply, Digital | 2.7V ~ 5.25V | 2.7V ~ 5.25V |
| Operating Temperature | -40°C ~ 85°C | -40°C ~ 125°C |
Frequently asked questions
What are the key differences between the ADC121S051CIMF and the ADC121S101CIMFX?
The primary difference is resolution and sample rate. The ADC121S051CIMF is a 12-bit, 500 kSPS successive-approximation ADC, while the ADC121S101CIMFX is a 12-bit, 1 MSPS successive-approximation ADC. Both are single-channel, single-ended devices in a SOT-23-6 package and share the same pinout, but the ADC121S101CIMFX offers twice the throughput of the ADC121S051CIMF.
Are the ADC121S051CIMF and ADC121S101CIMFX pin-compatible?
Yes. Both devices are offered in the same 6-pin SOT-23 package with an identical pinout (VIN, GND, CS, SCLK, SDATA, VA). This allows the ADC121S101CIMFX to be used as a higher-speed drop-in replacement for the ADC121S051CIMF, provided the system clock and timing are validated for the higher sample rate.
What is the resolution and sample rate of each device?
Both parts provide 12-bit resolution. The ADC121S051CIMF has a maximum throughput of 500 kSPS, whereas the ADC121S101CIMFX supports up to 1 MSPS. The higher sample rate of the ADC121S101CIMFX requires a correspondingly faster SCLK to complete conversion within the shorter acquisition window.
What supply voltage and reference configuration do these ADCs use?
Both devices operate from a single analog supply (VA) in the range of 2.7 V to 5.25 V and use the supply voltage as the reference, so the full-scale input range equals VA. They are specified for operation over the -40 °C to +85 °C industrial temperature range and are offered in the CIMFX/CIMF ordering variants.
What serial interface do the ADC121S051CIMF and ADC121S101CIMFX use?
Both use a SPI-compatible serial interface with chip-select (CS), serial clock (SCLK), and serial data out (SDATA) signals. The interface is compatible with standard SPI, QSPI, MICROWIRE, and DSP serial ports, allowing direct connection to most microcontrollers and digital signal processors.
Can the ADC121S101CIMFX replace the ADC121S051CIMF in an existing design?
In most cases yes, because the package, pinout, supply range, and interface are identical. However, the higher 1 MSPS rate of the ADC121S101CIMFX requires the host to supply a faster SCLK and to respect the shorter conversion/acquisition timing. The firmware timing and PCB signal integrity should be verified against the ADC121S101CIMFX datasheet before substitution.
What are the power consumption characteristics of these two ADCs?
Both devices are low-power CMOS ADCs that draw supply current proportional to throughput. Because the ADC121S101CIMFX can run at up to 1 MSPS, its power consumption at full rate is higher than that of the ADC121S051CIMF at 500 kSPS; at reduced throughput both parts scale down similarly. Consult the respective manufacturer datasheets for verified supply-current specifications at specific sample rates.
What input configuration and package do these ADCs provide?
Both are single-channel, single-ended ADCs with a 0 V to VA input range, housed in a 6-pin SOT-23 package. They are specified for the industrial temperature range and are intended for portable instrumentation, battery-powered systems, and general-purpose data acquisition where a small footprint and serial interface are required.