ADC0844CCN/NOPB - 8-Bit 4-Ch SAR ADC, 25ksps, 20-PDIP | TI
MPN: ADC0844CCN/NOPB ✓ פעילADC0844CCN/NOPB סקירה
An SAR ADC is a type of data converter that uses a binary search algorithm implemented with a capacitive DAC and a comparator to resolve one bit per clock cycle. SAR converters offer deterministic latency, low power, and excellent DC accuracy for moderate-speed precision measurements. ADC0844 sits within the data-converter IC family in the broader signal-chain hierarchy of analog->conditioning->conversion->processor, and bridges real-world sensors to microprocessors or microcontrollers.
Key features of the ADC0844 include 4 software-configurable analog input channels, an on-chip track-and-hold, ratiometric conversion that eliminates the need for an external precision reference, a microprocessor-compatible parallel interface with chip-select and read/write controls, and a maximum ±0.39% (1 LSB) linearity error. The 4/8-channel multiplexer can be set up as single-ended, differential, or pseudo-differential inputs without external signal conditioning.
The device's architecture uses a successive approximation register with an internal 256R resistor ladder. The reference input can be tied to the analog supply for direct ratiometric transducer measurements (potentiometers, strain gauges, thermistors) or to a precision external reference for absolute accuracy. The /CS, /RD, /WR, and /INT control the conversion sequence and allow easy interface to most 8-bit microprocessors.
Typical applications include process-control instrumentation, portable data loggers, multi-channel sensor front-ends, panel meters, and embedded measurement boards. Its parallel bus and 4-channel mux make it a natural fit for legacy 8051/PIC/HC11 designs that need multi-channel analog without an external analog MUX.
When designing with this part, observe proper PCB layout: keep analog and digital grounds separated and joined at a single point near the ADC ground pin. Add a 0.01uF bypass capacitor close to the VCC pin and a 0.1uF capacitor near the reference input to minimize digital switching noise coupling into the conversion result.
חלופות תחליף ישיר עבור ADC0844CCN/NOPB — אותו מארז, תואם פין-לפין. חלקים במארז שונה הדורשים עיבוד מחדש של ה-PCB אינם נכללים.
וריאנטים בסדרה זו
דגמים מאותה סדרה התואמים Drop-in עם ADC0844CCN/NOPB (אותו גורם צורה וטביעת רגל) — שונים ב Architecture, Data Interface, Sampling Rate, Input Type, Number of Input Channels.
ADC0848CCN/NOPB
✅ Drop-In📋 חלופה להתייחסות (לא בקטלוג)
ADC0844CCN
✅ Drop-In📋 חלופה להתייחסות (לא בקטלוג)
ADC0834BCN/NOPB
✅ Drop-Inצור קשר לקבלת מחיר
הצג גיליון נתונים ←ADC0838CCN/NOPB
✅ Drop-Inצור קשר לקבלת מחיר
הצג גיליון נתונים ←ADC0844CCJ
✅ Drop-In ⚠️ מפרטים לא מאומתים📋 חלופה להתייחסות (לא בקטלוג)
ADC0844BCN/NOPB
✅ Drop-In ⚠️ מפרטים לא מאומתים📋 חלופה להתייחסות (לא בקטלוג)
ADC0844CCN/NOPB דירוגים מרביים ומאפיינים חשמליים
| רזולוציה | 8 bit |
| Number of Channels | 4 |
| Conversion Type | SAR (Successive Approximation) |
| קצב דגימה | 25 ksps |
| Input Configuration | Single-Ended / Differential / Pseudo-Differential |
| Analog Supply Voltage | 4.5 V to 6.0 V |
| Digital Supply Voltage | 4.5 V to 6.0 V |
| טווח מתח כניסה | 0 V to VREF (single-ended) |
| Reference Input Resistance | 1.1 kohm minimum |
| Linearity Error (Max) | ±0.39% (1 LSB) |
| ממשק | Parallel (8-bit) with /CS, /RD, /WR, /INT |
| טמפרטורת פעולה | 0C to +70C (commercial) |
| מארז | 20-pin PDIP (N) |
| סוג הרכבה | Through-Hole |
| סטטוס RoHS | Compliant (NOPB suffix) |
תצורת פינים של ADC0844CCN/NOPB
| פין 1 | CH0 — Analog input channel 0 |
| פין 2 | CH1 — Analog input channel 1 |
| פין 3 | CH2 — Analog input channel 2 |
| פין 4 | CH3 — Analog input channel 3 |
| פין 5 | VREF — Voltage reference input |
| פין 6 | VCC — Analog +5V supply |
| פין 7 | GND — Analog ground |
| פין 8 | DB0 — Digital output bit 0 (LSB) |
| פין 9 | DB1 — Digital output bit 1 |
| פין 10 | DB2 — Digital output bit 2 |
| פין 11 | DB3 — Digital output bit 3 |
| פין 12 | DB4 — Digital output bit 4 |
| פין 13 | DB5 — Digital output bit 5 |
| פין 14 | DB6 — Digital output bit 6 |
| פין 15 | DB7 — Digital output bit 7 (MSB) |
| פין 16 | /CS — Chip select (active low) |
| פין 17 | /RD — Read strobe (active low) |
| פין 18 | /WR — Write strobe (active low) |
| פין 19 | /INT — Interrupt output (active low) |
| פין 20 | CLK IN — Clock input |
יישומים טיפוסיים
ADC0844CCN/NOPB מתאים עבור 6 יישוםs: Process Control Instrumentation, Portable Data Loggers, Multi-Channel Sensor Front-Ends, Digital Panel Meters, Legacy Embedded Measurement Boards, Industrial Automation I/O Modules.
Process Control Instrumentation
The ADC0844CCN/NOPB is well-suited for process-control panels where 4 channels of sensor data (temperature, pressure, flow, level) must be digitized for a PLC or HMI. The 25 ksps sampling rate easily handles typical 1-100 Hz transducer signals, while the 4-channel on-chip mux eliminates the need for an external analog MUX. The 8-bit parallel interface connects directly to legacy 8051 or PIC microcontrollers common in factory equipment. The ratiometric conversion feature ties VREF to the sensor excitation supply, automatically cancelling excitation drift for accurate bridge transducer readings.
מומלץ
Portable Data Loggers
Battery-powered data loggers benefit from the ADC0844CCN/NOPB's single +4.5V to +6.0V supply operation and CMOS low-power SAR design. Typical active supply current is approximately 1 mA per the TI datasheet - not in the recommended low-power range - so duty-cycling the conversions keeps average consumption low. The 4-channel mux allows logging of multiple environmental sensors (thermistor, humidity, light) through a single converter. The on-chip track-and-hold simplifies the analog front-end for slow-moving signals typical in environmental monitoring applications.
מומלץ
Multi-Channel Sensor Front-Ends
Embedded sensor boards reading multiple analog transducers benefit from the ADC0844CCN/NOPB's 4 input channels and parallel 8-bit interface. Each channel can be configured as single-ended, differential, or pseudo-differential without external signal conditioning. The SAR architecture provides deterministic conversion latency (one fixed number of clock cycles per conversion), which simplifies timing analysis in real-time sensor fusion firmware. The 20-pin PDIP through-hole package also suits hobbyist and prototyping applications where through-hole soldering is preferred over SMD.
מומלץ
Digital Panel Meters
Digital panel meters and bench instruments commonly integrate the ADC0844CCN/NOPB for its 4-channel capability and easy parallel interface to display-driver MCUs. The ratiometric conversion eliminates the need for an external precision reference when measuring potentiometric or bridge-type sensors, reducing BOM cost and calibration effort. The 25 ksps sampling rate is overkill for panel-meter update rates of 1-10 Hz, providing high noise averaging headroom. The commercial 0°C to +70°C temperature range covers indoor panel-meter operating environments.
מומלץ
Legacy Embedded Measurement Boards
Legacy 8051, HC11, and PIC-based measurement boards leverage the ADC0844CCN/NOPB's parallel 8-bit interface and memory-mapped read/write control. The /CS, /RD, /WR, /INT signals map directly to standard 8-bit microprocessor bus cycles, allowing the ADC to occupy a memory-mapped I/O address range with minimal glue logic. The 4-channel mux simplifies firmware by allowing sequential channel registration through the MUX address bus rather than channel-switching I/O expander chips.
מומלץ
Industrial Automation I/O Modules
Industrial I/O modules measuring 4-20 mA or 0-10 V field signals benefit from the ADC0844CCN/NOPB's differential input capability and ratiometric operation. Pseudo-differential mode allows rejection of common-mode ground offsets between the field wiring and the module's local ground - critical for industrial installations with long cable runs. The ±0.39% (1 LSB) linearity error suits general-purpose process monitoring where 1% accuracy is acceptable. The commercial-grade 0°C to 20°C range covers indoor industrial enclosure environments.
מומלץ
סיכום מוצרים מומלצים
נתוני עזר הנדסיים עבור ADC0844CCN/NOPB — השוואה, הנחיות תכנון ומידע על תאימות.
מדריך בחירה
השוואה עם חלופות
| פרמטר | מוצר זה | ADC0848CCN/NOPB | ADC0844CCN | ADC0834BCN/NOPB | ADC0838CCN/NOPB | ADC0844CCJ | ADC0844BCN/NOPB |
|---|---|---|---|---|---|---|---|
| Package | 20-PDIP (N) | 20-PDIP (N) - same | 20-PDIP (N) - same | 20-PDIP (N) - same | 20-PDIP (N) - same | 20-PDIP (N) - same | 20-PDIP (N) - same |
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments |
| Resolution | 8 bit | 8 bit | 8 bit | 8 bit | 8 bit | 8 bit | 8 bit |
| Number of Channels | 4 | 8 | 4 | 4 | 8 | 4 | 4 |
| Sampling Rate | 25 ksps | 25 ksps | 25 ksps | 25 ksps | 25 ksps | 25 ksps | 25 ksps |
| Digital Interface | Parallel (8-bit) | Parallel (8-bit) | Parallel (8-bit) | Serial MICrowire | Serial MICrowire | Parallel (8-bit) | Parallel (8-bit) |
| Supply Voltage | 4.5V to 6.0V | 4.5V to 6.0V | 4.5V to 6.0V | 4.5V to 6.0V | 4.5V to 6.0V | 4.5V to 6.0V | 4.5V to 6.0V |
| Linearity Error | ±0.39% (1 LSB) | ±0.39% (1 LSB) | ±0.39% (1 LSB) | ±0.39% (1 LSB) | ±0.39% (1 LSB) | ±0.39% (1 LSB) | Tighter (improved linearity grade) |
| RoHS Compliant | Yes (NOPB) | Yes (NOPB) | No (no NOPB) | Yes (NOPB) | Yes (NOPB) | No (no NOPB) | Yes (NOPB) |
מבדילים עיקריים
- 4-channel on-chip mux eliminates external MUX hardware (לעומתADC0808 (external-mux 8-bit ADC))
- Parallel 8-bit bus interface for high-throughput direct CPU access (לעומתADC0834BCN/NOPB (serial MICrowire))
- Ratiometric conversion eliminates need for external precision reference (לעומתExternal-precision-reference ADC designs)
הערות תכנון
Route the analog and digital grounds as separate traces that join at a single point near the ADC0848 GND pin (pin 7). Avoid running digital outputs (DB0-DB7) directly over the analog input traces or near the VREF pin to minimize digital switching noise coupling into the analog signal path. Place the 0.01uF and 0.1uF VCC bypass capacitors as close as physically possible to the VCC pin. The reference input pin (pin 5) must have a 0.1uF bypass capacitor within 5 mm of the pin.
Do not leave the /CS pin floating - tie it to logic high through a pull-up resistor to avoid spurious conversions. The /INT pin must be pulled high with a 10kohm pull-up to VCC; do not leave it floating or you will observe intermittent interrupts. When using the on-chip mux in differential or pseudo-differential configuration, both inputs must share a common-mode voltage within the input range specified by the TI datasheet - otherwise the converter will produce off-scale readings.
For ratiometric transducer measurements (potentiometers, strain gauges, thermistors), tie VREF directly to the transducer excitation supply. This automatic cancellation of supply drift is one of the ADC0844's key advantages. For absolute voltage measurements, use a precision external reference such as the TI REF02 or REF5050 to achieve better than ±0.5 LSB absolute error. Drive the reference pin with a low-impedance buffer if the source impedance exceeds the datasheet minimum of 1.1 kohm.
מידע על תאימות
NOPB suffix indicates lead-free (Pb-free) and RoHS-compliant packaging. AEC-Q100 not applicable for commercial-temperature-grade ADC. Halogen-free status not explicitly stated in source data - marked unknown per Data Authenticity Rules.