Part A
ADC128S022CIMTX
STマイクロエレクトロニクス
- Lifecycle
- Active
- Stock
- 1255 個数
- Package
- TSSOP-16
- Series
- データ取得 - アナログ/デジタルコンバータ (ADC)
Replacement verdict
Not a drop-in replacement
The ADC128S022CIMTX and ADC12138CIMSA are not drop-in replacements for one another. The ADC128S022CIMTX is an 8-channel, 12-bit successive-approximation ADC with a serial (SPI/QSPI/MICROWIRE/DSP-compatible) interface in a TSSOP-16 package, while the ADC12138CIMSA is a 4-channel, 12-bit successive-approximation ADC with a serial interface in an SOIC-20W package. The differences in channel count, package footprint, and pinout mean the two devices are not functionally interchangeable on the same PCB without redesign, and the ADC12138CIMSA should be evaluated as a separate design choice rather than a direct substitute.
Different channel count
Different package footprint
Different pinout
Different input configuration
Parts at a glance
Part B
ADC12138CIMSA
STマイクロエレクトロニクス
- Lifecycle
- Active
- Stock
- 8410 個数
- 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 | ADC128S022CIMTX | ADC12138CIMSA | Why it matters |
|---|---|---|---|
| Resolution | 12 bit | 12 bit | Both are 12-bit converters, so nominal quantization resolution is equivalent for substitutability. |
| Number of Input Channels | 8 single-ended | 4 differential / 8 single-ended | The ADC12138 supports differential inputs, enabling better common-mode rejection and noise immunity than the single-ended-only ADC128S022. |
| Sampling Rate | 200 kSPS | 114 kSPS | The ADC128S022 offers a higher maximum throughput, which matters for faster signal acquisition requirements. |
| Interface Type | SPI (serial) | SPI / Microwire (serial) | Both use serial interfaces, but the ADC12138 also supports Microwire, affecting host compatibility. |
| Supply Voltage | 2.7 V to 5.25 V | 3.0 V to 5.5 V | Slightly different supply ranges affect low-voltage operation and system rail compatibility. |
| Package | TSSOP-16 | SOIC-28 | Different package footprints and pin counts prevent direct drop-in board replacement. |
| Operating Temperature Range | -40 °C to +105 °C | -40 °C to +85 °C | The wider temperature range of the ADC128S022 suits harsher environments. |
| Input Type | Single-ended | Differential / single-ended | Differential capability in the ADC12138 enables measurement of floating or bipolar signals not directly supported by the ADC128S022. |
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Full specification comparison
Use manufacturer datasheets as the final authority.
| Specification | ADC128S022CIMTX | ADC12138CIMSA |
|---|---|---|
| Part Status | Obsolete | Obsolete |
| Number of Bits | 12 | 12 |
| Sampling Rate (Per Second) | - | 114k |
| Number of Inputs | 8 | 4, 8 |
| Input Type | Single Ended | Differential, Pseudo-Differential, Single Ended |
| Data Interface | SPI, DSP | SPI |
| Configuration | MUX-S/H-ADC | MUX-S/H-ADC |
| Ratio - S / H: ADC | 1:1 | 1:1 |
| Number of A / D Converters | - | 1 |
| Architecture | SAR | SAR |
| Reference Type | Supply | External |
| Voltage - Supply, Analog | 2.7V ~ 5.25V | 3V ~ 5.5V |
| Voltage - Supply, Digital | 2.7V ~ 5.25V | 3V ~ 5.5V |
| Operating Temperature | -40°C ~ 105°C | -40°C ~ 85°C |
| Mounting Type | - | Surface Mount |
| Base Product Number | - | ADC121 |
| Sampling Rate(Per Second) | 200k | - |
| Number of A/D Converters | 1 | - |
Frequently asked questions
What are the key differences between the ADC128S022CIMTX and the ADC12138CIMSA?
The ADC128S022CIMTX is an 8-channel, 12-bit successive-approximation ADC with a maximum throughput of 200 kSPS, supplied in a 16-pin TSSOP package and operating from a 2.7 V to 5.25 V supply. The ADC12138CIMSA is a 12-bit successive-approximation ADC with a 4-channel differential/8-channel single-ended input multiplexer, a maximum conversion rate of 114 kSPS, supplied in a 28-pin SSOP package and operating from a 3.0 V to 5.5 V supply. They differ in channel configuration, throughput, package, and supply range.
Are the ADC128S022CIMTX and ADC12138CIMSA pin-to-pin compatible?
No. The ADC128S022CIMTX uses a 16-pin TSSOP package, while the ADC12138CIMSA uses a 28-pin SSOP package. The pin counts and package footprints differ, so they are not drop-in replacements and require different PCB land patterns.
What is the maximum sampling rate of each device?
The ADC128S022CIMTX supports a maximum throughput of 200 kSPS. The ADC12138CIMSA supports a maximum conversion rate of 114 kSPS. The ADC128S022CIMTX therefore offers a higher maximum sampling rate.
How do the input channel configurations compare?
The ADC128S022CIMTX provides 8 single-ended input channels. The ADC12138CIMSA provides a multiplexer that can be configured as 4 differential input pairs or 8 single-ended inputs. Designs requiring differential inputs should account for this difference.
What are the supply voltage ranges for these two ADCs?
The ADC128S022CIMTX operates from a single supply of 2.7 V to 5.25 V. The ADC12138CIMSA operates from a single supply of 3.0 V to 5.5 V. Both are compatible with common 3.3 V and 5 V system rails, but the ADC128S022CIMTX supports a slightly lower minimum supply voltage.
Do both devices use a serial interface?
Yes. Both the ADC128S022CIMTX and the ADC12138CIMSA use an SPI-compatible serial interface for communication with a host controller, which allows them to share a common serial bus architecture in most system designs.
Can the ADC12138CIMSA be used as a direct substitute for the ADC128S022CIMTX?
Not directly. Although both are 12-bit successive-approximation ADCs with serial interfaces, they differ in package (28-pin SSOP vs 16-pin TSSOP), maximum throughput (114 kSPS vs 200 kSPS), input multiplexer configuration, and supply range. A substitution requires PCB redesign and validation against the target design requirements.