Part A
ADC121S101CIMF
Texas Instruments
- Lifecycle
- Active
- Stock
- 3205 PCS
- Package
- SOT-23-6
- Series
- Acquisition de données - Convertisseur analogique - numérique (ADC)
Replacement verdict
Compatible functional replacement candidate
The ADC121S101CIMF is a functionally compatible replacement candidate for the ADC121S021CIMF, sharing the same 12-bit SAR architecture, single-channel single-ended input, SPI interface, and SOT-23-6 footprint. The primary distinction is conversion throughput, where the ADC121S101 offers a higher sampling rate; designers should validate timing margins and power budget against the target application before substitution.
Resolution
High match
Package Type
High match
Interface Type
High match
Sampling Rate
Validation required
Parts at a glance
Part B
ADC121S021CIMF
Texas Instruments
- Lifecycle
- Active
- Stock
- 6879 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 | ADC121S021CIMF | ADC121S101CIMF | 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. |
| Interface Type | SPI / QSPI / MICROWIRE compatible | SPI / QSPI / MICROWIRE compatible | Identical serial interfaces allow either part to connect to the same host controller without protocol changes. |
| Supply Voltage Range | 2.7 V to 5.25 V | 2.7 V to 5.25 V | Matching supply ranges mean both parts can operate from the same system rail without level shifting. |
| Power Consumption (Typical at 3.6 V) | Approximately 1.5 mW at 200 kSPS | Approximately 2.5 mW at 1 MSPS | Lower power per conversion in the ADC121S021 benefits battery-powered designs, while the ADC121S101 trades power for speed. |
| Package | SOT-23-6 | SOT-23-6 | Identical package and pinout allow drop-in PCB replacement without layout changes. |
| Operating Temperature Range | -40 °C to +125 °C | -40 °C to +125 °C | Same industrial temperature range ensures both parts suit the same environmental conditions. |
| Input Bandwidth / Throughput Class | Up to 200 kSPS conversion rate | Up to 1 MSPS conversion rate | The higher conversion rate of the ADC121S101 supports faster-changing signals, while the ADC121S021 is adequate for slower sensors. |
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Full specification comparison
Use manufacturer datasheets as the final authority.
| Specification | ADC121S101CIMF | ADC121S021CIMF |
|---|---|---|
| Part Status | Obsolete | Not For New Designs |
| Number of Bits | 12 | 12 |
| Sampling Rate(Per Second) | 1M | 200k |
| 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 ~ 125°C | -40°C ~ 85°C |
Frequently asked questions
What are the key differences between the ADC121S021CIMF and ADC121S101CIMF?
The ADC121S021CIMF is a 12-bit, 200 kSPS successive-approximation ADC with a single-ended input and an SPI-compatible serial interface, while the ADC121S101CIMF is a 12-bit, 1 MSPS successive-approximation ADC with a single-ended input and the same SPI-compatible serial interface. The primary difference is the maximum sampling rate: 200 kSPS for the ADC121S021 versus 1 MSPS for the ADC121S101.
Are the ADC121S021CIMF and ADC121S101CIMF pin-compatible?
Yes. Both devices are offered in the same 6-pin SOT-23 package (CIMF suffix) with the same pinout: VIN, GND, VA, CS, SCLK, and DOUT. This pin compatibility allows the ADC121S101CIMF to be used as a higher-speed drop-in alternative to the ADC121S021CIMF, provided the system timing and power budget support the higher sampling rate.
What is the resolution and interface type of both devices?
Both the ADC121S021CIMF and ADC121S101CIMF are 12-bit resolution ADCs featuring a serial peripheral interface (SPI) compatible with standard microcontrollers and DSPs. They support a 3-wire or 4-wire SPI connection using CS, SCLK, and DOUT pins.
What are the supply voltage and power consumption specifications?
Both devices operate from a single analog supply (VA) of 2.7 V to 5.25 V. The ADC121S021CIMF typically consumes about 1.5 mW at 3.3 V and 200 kSPS, while the ADC121S101CIMF typically consumes about 2.5 mW at 3.3 V and 1 MSPS. Both feature a power-down mode that reduces consumption to a few microwatts when not converting.
Can the ADC121S101CIMF replace the ADC121S021CIMF in an existing design?
In most cases yes, because both share the same package, pinout, supply range, and SPI interface. However, the designer must verify that the host SPI clock and timing can support the higher 1 MSPS throughput of the ADC121S101CIMF, and that the increased power consumption is acceptable. The ADC121S101CIMF can also be operated at lower sampling rates if needed.
What is the input voltage range and reference configuration of these ADCs?
Both the ADC121S021CIMF and ADC121S101CIMF use the supply voltage (VA) as the reference, so the input voltage range is 0 V to VA. They are single-ended input devices with a track-and-hold front end, suitable for DC and low-frequency AC signals within the supply rail.
What are the operating temperature ranges for these components?
Both the ADC121S021CIMF and ADC121S101CIMF are specified over the industrial temperature range of −40 °C to +85 °C, making them suitable for industrial and embedded applications.