ADS7841PBG4 - 12-Bit 4-Ch 200kHz SAR ADC | Texas Instruments
MPN: ADS7841PBG4 ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $7.42 | $7.42 |
| 10 | $6.68 | $66.80 |
| 100 | $5.21 | $521.00 |
| 500 | $4.67 | $2,335.00 |
| 1,000 | $4.12 | $4,120.00 |
ADS7841PBG4 Overview
A SAR ADC is a type of data converter that uses a binary-search successive-approximation algorithm to digitize an analog input in N clock cycles for N bits of resolution. SAR ADCs sit in the broader data-converter hierarchy of analog-to-digital converters, which also include delta-sigma, pipeline, and flash architectures. Within TI's portfolio, SAR ADCs are the workhorse choice for medium-speed (10 kSPS to 1 MSPS), medium-resolution (8 to 16 bit) multiplexed applications where low latency, deterministic throughput, and simple SPI/QSPI/MICROWIRE-compatible serial interfaces are required.
Key features of the ADS7841 include single +2.7V to +5.5V supply operation, a software-controlled shutdown mode that drops supply current to under 1 uA, an analog input range of 0V to VREF, and a reference voltage (VREF) that can be varied from 100 mV to VCC. The four analog inputs are selected by a 2-bit address and a 1-bit single-ended/differential control word clocked into the DIN pin, making the part pin-compatible with industry-standard touch-screen controllers of the same era. The 16-PDIP package supports breadboard and through-hole prototyping as well as legacy industrial backplanes.
Typical applications include industrial process control, portable data acquisition, isolated sensor front ends, pen/touch input replacement, and battery-powered instrumentation. The wide supply range and 1 uA shutdown current also make the part suitable for power-constrained remote-sensor nodes where the ADC is duty-cycled awake only when a measurement is needed.
When designing with the ADS7841PBG4, decouple VCC with a 0.1 uF ceramic capacitor placed within 5 mm of the supply pin, and bypass VREF with at least 1 uF of effective capacitance to keep the reference stable across conversions. The serial clock (DCLK) frequency is limited to 2.048 MHz at VCC = 5V (derate to 1.2 MHz at 2.7V) - the host MCU must respect this ceiling for reliable conversions. CS must be brought high after the 24th SCLK to complete the conversion cycle; floating CS mid-frame yields a corrupted sample. This page synthesizes distributor pricing, verified drop-in alternatives, and practical design notes that go beyond the manufacturer datasheet to help engineers select, source, and integrate the ADS7841PBG4 with confidence.
Drop-in alternatives for ADS7841PBG4 — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Variants in this series
Same-series models that are drop-in compatible with ADS7841PBG4 (same form factor and footprint) — differing in Package, Sampling Rate, Input Type, Resolution, Operating Temperature.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
ADS7841P
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
ADS7841PB
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
ADS7841-Q1
✅ Drop-In📋 Reference alternative (not in catalog)
ADS7841EG4
✅ Drop-In📋 Reference alternative (not in catalog)
ADS7841E/2K5G4
✅ Drop-In✓ In Stock
$5.7 / Unit
View Datasheet →ADS7841PBG4 Maximum Ratings & Electrical Characteristics
| Resolution | 12 bits (programmable to 8 bits) |
| Number of Input Channels | 4 single-ended or 2 differential |
| Architecture | SAR (Successive Approximation) |
| Sampling Rate | 200 kSPS |
| Conversion Time | 3.75 us |
| Data Interface | Serial (SPI/QSPI/MICROWIRE-compatible) |
| INL (Max) | +/-1 LSB |
| DNL (Max) | +/-1 LSB |
| SINAD | 72 dB |
| Missing Codes | None (guaranteed) |
| Supply Voltage | 2.7 V to 5.5 V (single supply) |
| Reference Voltage (VREF) | 100 mV to VCC |
| Analog Input Range | 0 V to VREF |
| Power Dissipation (Typ, 200 kHz, VCC=5V) | 2 mW |
| Shutdown Current | < 1 uA |
| Operating Temperature | -40 C to +85 C (industrial) |
| Package | 16-PDIP (0.300 in, 7.62 mm) |
| Mounting Type | Through-Hole |
| MSL Level | 1 (unlimited) |
| RoHS Status | Compliant |
| Lead-Free | Yes |
ADS7841PBG4 Pin Configuration
| Pin 1 | VCC — Analog +2.7V to +5.5V supply |
| Pin 2 | AIN0 — Analog input channel 0 |
| Pin 3 | AIN1 — Analog input channel 1 |
| Pin 4 | AIN2 — Analog input channel 2 |
| Pin 5 | AIN3 — Analog input channel 3 |
| Pin 6 | COM — Common reference for single-ended conversions |
| Pin 7 | VREF — Reference voltage input (100 mV to VCC) |
| Pin 8 | AGND — Analog ground |
| Pin 9 | DGND — Digital ground |
| Pin 10 | SHDN — Shutdown control (active low, tie high for normal operation) |
| Pin 11 | DOUT — Serial data output |
| Pin 12 | DIN — Serial data input (channel select) |
| Pin 13 | CS — Chip select (active low) |
| Pin 14 | DCLK — Serial data clock |
| Pin 15 | BUSY — Conversion-in-progress output (active high) |
| Pin 16 | VCC — Digital +2.7V to +5.5V supply (tied to pin 1) |
Typical Applications
ADS7841PBG4 is suitable for 6 applications: Industrial Process Control Multi-Sensor Acquisition, Portable Battery-Powered Data Acquisition, Legacy Touch-Screen Controller Replacement, Isolated Multi-Channel Sensor Front End, Test and Measurement Instrumentation, Pen-Digitizer and Graphics Tablet Input.
Industrial Process Control Multi-Sensor Acquisition
The ADS7841PBG4's 4-channel single-ended or 2-channel differential input multiplexer makes it a strong fit for industrial process control front ends where multiple sensors (temperature, pressure, flow, level) must be sampled from a single ADC. Its 200 kSPS throughput is well matched to multiplexed multi-sensor loops that need 1-10 kHz per-channel update rates. The 72 dB SINAD and +/-1 LSB INL/DNL deliver the linearity required for closed-loop control. Placed downstream of a 4-20 mA loop receiver or a thermocouple/RTD signal conditioner, the part provides the channel density and accuracy PLC and SCADA systems require.
Recommended
Portable Battery-Powered Data Acquisition
The ADS7841PBG4's 2 mW typical power dissipation at 200 kHz and sub-1 uA shutdown current suit battery-powered portable data acquisition loggers. The 2.7V-5.5V single-supply range is compatible with 2-3 cell alkaline, 1-2 cell Li-Ion, or 3.3V system rails. The serial interface (SPI/QSPI/MICROWIRE) interfaces directly to low-power MCUs like MSP430 or STM32L. For remote sensor nodes, the host can duty-cycle the ADC awake for short measurement bursts and return it to shutdown mode, stretching battery life across multi-year deployments.
Recommended
Legacy Touch-Screen Controller Replacement
The ADS7841PBG4 was originally designed as a 4-wire resistive touch-screen controller and remains pin-compatible with that legacy interface. Its 4 single-ended analog inputs connect to the X+, X-, Y+, Y- touch-panel signals, and its 12-bit resolution delivers approximately 0.025% of full-scale touch-position accuracy - adequate for industrial HMI and POS terminals. The synchronous serial interface is identical to legacy touch-screen controllers, so firmware rarely needs modification. Industrial -40C to +85C operation supports outdoor and factory-floor HMI panels.
Recommended
Isolated Multi-Channel Sensor Front End
The ADS7841PBG4's 4-channel mux combined with low 2 mW dissipation simplifies isolated front-end design: drive the ADC from the isolated side and route the digital serial interface across an optocoupler or digital isolator. Each of the four inputs can connect to a different isolated sensor (current shunt, thermocouple, RTD bridge), and a single isolation barrier serves all four channels, reducing BOM cost. The 2.7V-5.5V supply is compatible with isolated 5V or 3.3V rails generated from small isolated DC-DC modules. The serial interface is inherently low-EMI, simplifying isolation barrier design.
Recommended
Test and Measurement Instrumentation
The ADS7841PBG4's 12-bit resolution with pin-programmable 8-bit mode and 200 kSPS throughput fits bench-top test and measurement instruments that need fast, accurate multi-channel acquisition. The 8-bit mode is useful for high-speed scope-like digitizers where 1 MSPS effective aggregate throughput across 4 channels is desired, while 12-bit mode delivers precision for DMM and LCR meter front ends. The 16-PDIP through-hole package is ideal for hand-built prototypes and small-batch lab instruments. The synchronous serial interface simplifies connection to FPGAs and high-speed DSPs.
Recommended
Pen-Digitizer and Graphics Tablet Input
The ADS7841PBG4 was originally designed for pen-digitizer and graphics-tablet applications, with its 4 single-ended input channels connecting to the X-plate, Y-plate, and pressure-sensor signals of an EMR pen system. Its 200 kSPS sampling rate supports real-time pen tracking at 100-200 points per second, and its 12-bit resolution gives approximately 4096 x 4096 coordinate resolution across a standard A4 digitizing surface. The synchronous serial interface connects to the host MCU with minimal GPIO, and the 1 uA shutdown mode extends battery life in wireless pen tablets.
Recommended
Recommended Products Summary
Engineering reference data for ADS7841PBG4 — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ADS7841P | ADS7841PB | ADS7841-Q1 | ADS7841EG4 | ADS7841E/2K5G4 |
|---|---|---|---|---|---|---|
| Package | 16-PDIP (through-hole) | 16-PDIP - same | 16-PDIP - same | 16-PDIP - same | 16-SSOP (SMT) | 16-SSOP (SMT) |
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments |
| Resolution | 12 bits (8-bit programmable) | 12 bits | 12 bits | 12 bits | 12 bits | 12 bits |
| Sampling Rate | 200 kSPS | 200 kSPS | 200 kSPS | 200 kSPS | 200 kSPS | 200 kSPS |
| Input Channels | 4 SE / 2 DIFF | 4 SE / 2 DIFF | 4 SE / 2 DIFF | 4 SE / 2 DIFF | 4 SE / 2 DIFF | 4 SE / 2 DIFF |
| Supply Voltage | 2.7V to 5.5V | 2.7V to 5.5V | 2.7V to 5.5V | 2.7V to 5.5V | 2.7V to 5.5V | 2.7V to 5.5V |
| Temperature Range | -40C to +85C (industrial) | 0C to +70C (commercial) | 0C to +70C (commercial) | -40C to +125C (automotive) | -40C to +85C (industrial) | -40C to +85C (industrial) |
| Automotive Grade (AEC-Q100) | No | No | No | Yes | No | No |
| Power Dissipation (Typ) | 2 mW | 2 mW | 2 mW | 2 mW | 2 mW | 2 mW |
Key Differentiators
- Through-hole 16-PDIP package for legacy and breadboard designs (vs ADS7841EG4 (16-SSOP surface-mount))
- Industrial temperature range -40C to +85C (vs ADS7841P (commercial 0C to +70C))
- Programmable 8-bit or 12-bit resolution (vs Fixed-resolution 12-bit SAR ADCs)
- Sub-1 uA shutdown current for battery-powered duty-cycled operation (vs ADS1110 (continuous-conversion 16-bit delta-sigma))
Design Notes
Decouple VCC (pins 1 and 16) with a 0.1 uF ceramic capacitor placed within 5 mm of the supply pins, plus a bulk 1-10 uF tantalum or ceramic capacitor on the same rail. The ADS7841PBG4 draws brief current spikes during SAR conversion, and insufficient decoupling causes reference sag that degrades linearity. For lowest noise, use a separate analog LDO (e.g., TPS7A4533) for the ADS7841 VCC rather than sharing the digital 3.3V or 5V rail directly with the host MCU.
Route analog signals (AIN0-AIN3, COM, VREF) and digital signals (DCLK, DIN, DOUT, CS, BUSY) on opposite sides of the package to minimize digital-to-analog crosstalk. Place the AGND and DGND pins on a single low-impedance ground plane, with a star-ground connection at the ADC's AGND pin. Keep the DCLK trace short and route it away from the analog inputs; clock edges couple into the sample-and-hold and degrade SNR if the trace is long or parallel to analog traces.
The DCLK frequency is limited to 2.048 MHz at VCC = 5V and 1.2 MHz at VCC = 2.7V. Exceeding these limits yields corrupted conversion results because the internal SAR timing margin is violated. CS must be brought high after the 24th SCLK falling edge to complete the conversion; if CS is left low, the BUSY signal stays asserted and no new conversion is initiated. According to the TI datasheet, the part requires 24 DCLK cycles per conversion in 12-bit mode and 16 DCLK cycles in 8-bit mode.
Do not operate the ADS7841PBG4 below VREF < 100 mV or above VREF = VCC - the input multiplexer and reference buffer are not specified outside this range. The SHDN pin must be tied high (or driven by a GPIO) for normal operation; floating SHDN puts the part in an indeterminate state. The BUSY signal is open-drain on some revisions and push-pull on others - check your silicon revision and use the appropriate pull-up if needed. The COM pin must be connected to the low-side of the signal source for single-ended conversions; leaving it floating introduces large gain errors.
Compliance Information
RoHS compliant and lead-free per TI product page. The PBG4 (industrial) is not AEC-Q100 qualified; choose ADS7841-Q1 for automotive applications. Halogen-free status not explicitly stated in available data.
