Part A
ADS7844EB
Texas Instruments
- Lifecycle
- Active
- Stock
- 3681 PCS
- Package
- SSOP-20
- Series
- Acquisition de données - Convertisseur analogique - numérique (ADC)
Replacement verdict
Compatible functional replacement candidate
The ADS7841E/2K5G4 is a functionally compatible replacement candidate for the ADS7844EB in many 12-bit SAR ADC applications, sharing the same resolution, SPI-compatible serial interface, and single-supply operation. However, the ADS7844EB offers a 4-channel input multiplexer with single-ended or differential configurations, while the ADS7841E/2K5G4 provides a 4-channel single-ended input structure, so channel configuration flexibility and package footprint must be validated against the target design before substitution.
Resolution
High match
Serial Interface
High match
Input Configuration
Validation required
Package Type
Validation required
Parts at a glance
Part B
ADS7841E/2K5G4
Texas Instruments
- Lifecycle
- Active
- Stock
- 5974 PCS
- Package
- SSOP-16
- 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 | ADS7844EB | ADS7841E/2K5G4 | Why it matters |
|---|---|---|---|
| Number of Input Channels | 8 (single-ended) / 4 (differential) | 4 (single-ended) / 2 (differential) | Determines how many analog signals can be measured; the ADS7844 supports twice as many channels, so it is not a drop-in replacement where 8 channels are required. |
| Resolution | 12 bit | 12 bit | Both provide 12-bit resolution, so measurement precision is equivalent and substitutable in this respect. |
| Sampling Rate | 200 kSPS | 200 kSPS | Identical maximum throughput means timing and bandwidth requirements are met by either device. |
| Supply Voltage | 2.7 V to 5.25 V | 2.7 V to 5.25 V | Same supply range allows operation from common 3 V or 5 V rails without redesign. |
| Interface | SPI / QSPI / Microwire compatible serial | SPI / QSPI / Microwire compatible serial | Identical serial interface protocol simplifies firmware and hardware substitution. |
| Package | SSOP-20 | SOIC-16 | Different package and pin count require PCB footprint changes; the parts are not physically interchangeable. |
| Input Type | Single-ended / differential | Single-ended / differential | Both support single-ended and differential inputs, preserving signal conditioning flexibility. |
| Operating Temperature Range | -40 °C to +85 °C | -40 °C to +85 °C | Same industrial temperature range means both suit the same environmental conditions. |
Need help validating a replacement?
Send your BOM and application constraints for technical and sourcing review.
Full specification comparison
Use manufacturer datasheets as the final authority.
| Specification | ADS7844EB | ADS7841E/2K5G4 |
|---|---|---|
| Supplier | - | Texas Instruments |
| Part Status | Active | Obsolete |
| Number of Bits | 12 | 12 |
| Sampling Rate(Per Second) | 200k | 200k |
| Number of Inputs | 4, 8 | 4 |
| Input Type | Differential, 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 ~ 3.6V, 5V | 2.7V ~ 3.6V, 5V |
| Voltage - Supply, Digital | 2.7V ~ 3.6V, 5V | 2.7V ~ 3.6V, 5V |
| Operating Temperature | -40°C ~ 85°C | -40°C ~ 125°C |
Frequently asked questions
What are the key architectural differences between the ADS7844EB and the ADS7841E/2K5G4?
The ADS7844EB is an 8-channel, 12-bit successive-approximation register (SAR) analog-to-digital converter with a serial interface, housed in a 20-lead SSOP package. The ADS7841E/2K5G4 is a 4-channel, 12-bit SAR ADC in a 16-lead SSOP package, supplied in tape-and-reel format (2K5 indicates 2500 units per reel). The primary differences are channel count (8 vs. 4) and package pin count (20 vs. 16).
Are the ADS7844EB and ADS7841E/2K5G4 pin-compatible?
No. The ADS7844EB uses a 20-lead SSOP package, while the ADS7841E/2K5G4 uses a 16-lead SSOP package. The differing pin counts and pin functions prevent direct PCB footprint compatibility without layout changes.
Do both devices share the same resolution and sampling rate?
Yes. Both the ADS7844EB and ADS7841E/2K5G4 are 12-bit SAR ADCs with a specified throughput of 200 kSPS, per the respective Texas Instruments datasheets.
What is the difference in input channel configuration between the two parts?
The ADS7844EB provides 8 input channels that can be configured as single-ended or differential pairs. The ADS7841E/2K5G4 provides 4 input channels, also configurable as single-ended or differential. Designs requiring more than four analog inputs must use the ADS7844EB or an external multiplexer.
Are the supply voltage and reference requirements the same for both devices?
Both devices operate from a single supply in the 2.7 V to 5.25 V range and support an external reference voltage (VREF) that sets the full-scale input range. The reference input range and supply specifications are consistent across both datasheets, allowing similar analog front-end design practices.
What is the significance of the "2K5" suffix on the ADS7841E/2K5G4?
The "2K5" suffix denotes tape-and-reel packaging with 2,500 units per reel, and the "G4" suffix indicates Pb-free (RoHS-compliant) construction per Texas Instruments ordering conventions. The ADS7844EB is supplied in tube packaging; designers should confirm the exact ordering code for reel availability if automated assembly is required.
Can the ADS7841E/2K5G4 be used as a drop-in replacement for the ADS7844EB in an existing design?
No. Despite sharing 12-bit resolution, 200 kSPS throughput, and a similar serial interface, the devices differ in channel count (4 vs. 8) and package (16-lead vs. 20-lead SSOP). A drop-in replacement is not possible; the PCB layout, channel count requirements, and firmware channel-addressing must be revalidated.