Part A
ADC121S021CIMF
Texas Instruments
- Lifecycle
- Active
- Stock
- 6879 PCS
- Package
- SOT-23-6
- Series
- Acquisição de dados - Analogo para Convertedores Digitais (ADC)
Replacement verdict
Compatible functional replacement candidate
The ADC121S021CIMF and ADC121S101CIMFX are both 12-bit, single-channel SAR ADCs from Texas Instruments in the same SOT-23-6 package, sharing an identical pinout and SPI-compatible serial interface. The primary distinction is sampling rate: the ADC121S101CIMFX offers a higher throughput of up to 1 MSPS versus 200 kSPS for the ADC121S021CIMF. Because the faster device is form-factor and interface compatible, it can generally serve as a functional substitute where the higher conversion rate is acceptable, provided the system timing and power budget are validated against the target design.
Resolution
High match
Package Type
High match
Interface Type
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
- Acquisição de dados - Analogo para Convertedores Digitais (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 | ADC121S021CIMF | ADC121S101CIMFX | Why it matters |
|---|---|---|---|
| Resolution | 12 bit | 12 bit | Both converters provide 12-bit resolution, so quantization step size is equivalent for a given reference voltage. |
| Sampling Rate | 200 kSPS | 1 MSPS | The ADC121S101 supports a much higher throughput, enabling faster signal acquisition and wider input bandwidth than the ADC121S021. |
| Number of Input Channels | 1 single-ended | 1 single-ended | Both are single-channel devices, so channel count does not differentiate them for multi-signal applications. |
| Supply Voltage Range | 2.7 V to 5.25 V | 2.7 V to 5.25 V | Identical supply range allows either part to operate from the same system rail without level shifting. |
| Interface Type | SPI / QSPI / MICROWIRE compatible | SPI / QSPI / MICROWIRE compatible | Both use the same serial interface, simplifying firmware and pin-compatible drop-in replacement. |
| Package | SOT-23-6 | SOT-23-6 | Same package footprint enables direct board-level substitution without layout changes. |
| Operating Temperature Range | -40 °C to +85 °C | -40 °C to +85 °C | Equivalent temperature ratings mean both suit the same industrial and commercial environments. |
| Power Consumption (Typical) | Lower (200 kSPS throughput) | Higher (1 MSPS throughput) | The faster ADC121S101 generally draws more supply current at full rate, affecting power budget in battery-powered designs. |
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Full specification comparison
Use manufacturer datasheets as the final authority.
| Specification | ADC121S021CIMF | ADC121S101CIMFX |
|---|---|---|
| Supplier | - | Texas Instruments |
| Part Status | Not For New Designs | Obsolete |
| Number of Bits | 12 | 12 |
| Sampling Rate(Per Second) | 200k | 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 ADC121S021CIMF and the ADC121S101CIMFX?
The ADC121S021CIMF is a 12-bit, 200 kSPS successive-approximation ADC with a single-ended input and an SPI-compatible serial interface, supplied in a 6-pin SOT-23 package. The ADC121S101CIMFX is a 12-bit, 1 MSPS successive-approximation ADC with a single-ended input and an SPI-compatible serial interface, supplied in a 6-pin SOT-23 package. The primary differences are the maximum sampling rate (200 kSPS vs 1 MSPS) and the corresponding power consumption and timing characteristics.
Are the ADC121S021CIMF and ADC121S101CIMFX pin-compatible?
Both devices are offered in the same 6-pin SOT-23 package with the same pin functions (VIN, GND, VA, CS, SCLK, and DOUT), so they are pin-compatible. However, the higher sampling rate of the ADC121S101CIMFX requires the host to support the faster SCLK timing, so firmware and timing must be validated before substitution.
What is the maximum sampling rate of each device?
The ADC121S021CIMF supports a maximum conversion rate of 200 kSPS. The ADC121S101CIMFX supports a maximum conversion rate of 1 MSPS. Both are 12-bit successive-approximation ADCs, so the ADC121S101CIMFX provides five times the throughput of the ADC121S021CIMF.
Do both devices use the same serial interface?
Yes. Both the ADC121S021CIMF and the ADC121S101CIMFX use an SPI-compatible serial interface with CS, SCLK, and DOUT signals. The interface protocol is compatible, but the maximum SCLK frequency and conversion timing differ because of the different sampling rates, so the host clock must be configured accordingly.
What is the supply voltage range for these ADCs?
Both the ADC121S021CIMF and the ADC121S101CIMFX operate from a single analog supply (VA) in the 2.7 V to 5.25 V range, as specified in the manufacturer datasheets. The digital interface levels are referenced to the same supply, so the host logic level should match the selected VA.
Can the ADC121S101CIMFX replace the ADC121S021CIMF in an existing design?
Because both parts share the same 6-pin SOT-23 footprint and SPI-compatible interface, the ADC121S101CIMFX can generally replace the ADC121S021CIMF when the host can support the higher 1 MSPS throughput and the associated faster SCLK timing. The design should be validated against the ADC121S101CIMFX datasheet for timing, power, and accuracy before substitution.
How does power consumption compare between the two devices?
Power consumption scales with sampling rate in successive-approximation ADCs. The ADC121S101CIMFX, operating at up to 1 MSPS, draws more supply current at full rate than the ADC121S021CIMF at its 200 kSPS maximum. For low-power, low-throughput designs the ADC121S021CIMF is the lower-power choice, while the ADC121S101CIMFX is intended for higher-speed applications.
What is the resolution and input configuration of these ADCs?
Both the ADC121S021CIMF and the ADC121S101CIMFX are 12-bit successive-approximation ADCs with a single-ended analog input. They are members of the same ADC121S0xx family, differing primarily in maximum sampling rate rather than resolution or input topology.