MAX1295BCEI - 265ksps 12-Bit 6-Ch +3V ADC | Maxim Integrated
MPN: MAX1295BCEI ✓ فعالMAX1295BCEI جائزہ
An ADC (analog-to-digital converter) is a mixed-signal integrated circuit that samples continuous analog voltages and outputs discrete binary codes, bridging real-world sensors (temperature, pressure, strain, current) to digital microcontrollers, DSPs, or FPGAs. Successive-approximation (SAR) ADCs such as the MAX1295 use an internal DAC and comparator to perform a binary search each conversion cycle, providing a strong trade-off between speed, accuracy, and low power. They sit in the broader taxonomy: ADC -> data converter -> mixed-signal IC -> semiconductor. When paired with an internal 2.5V reference, a 12-bit SAR ADC can resolve 2.5V/4096 = 610 µV LSB steps directly with no external reference IC.
Key features of the MAX1295BCEI include 12-bit resolution with ±0.5 LSB DNL/INL, software-selectable input channel configuration, hardware- and software-controlled power-down modes (as low as 1 µA typical for battery-friendly designs), an internal 2.5V reference (or external reference override), and a wide digital +3V single-supply rail. The parallel interface connects directly to microcontrollers or ASICs and supports 100 ns minimum data-access time, simplifying timing closure in system-on-chip designs.
The MAX1295 family uses a charge-redistribution SAR architecture with an input track-and-hold, supporting single-ended or pseudo-differential conversions. Automatic power-down between conversions plus a fast wake-up time yield a typical supply current of ~1.7 mA at 265 ksps, dropping to ~1 µA in shutdown, which is critical for battery-powered data-acquisition systems.
Typical applications of the MAX1295BCEI include multi-channel data acquisition in industrial control loops, portable/battery-powered instrumentation, system monitoring boards, motor-control feedback paths, and process-control sensor interfaces. Designers select this part when 12-bit resolution is enough, multiple sensor channels are required, and parallel (rather than serial) output is desired for fast host-side reads.
One design consideration: although the MAX1295 supports both internal and external references, an external reference improves gain accuracy and temperature drift in precision measurements. Use low-impedance source driving and place a 0.1 µF + 10 µF decoupling pair near the supply pin to keep digital switching noise out of the analog front end.
This page synthesizes distributor pricing, drop-in same-package alternatives (MAX1294BCEI/MAX1295BCEI+/MAX1295BCEI+T/MAX1295AEEI/MAX1295BEEI), 28-pin pinout data and practical design notes not found in the standalone manufacturer datasheet.
کے لیے ڈراپ اِن متبادل MAX1295BCEI — یکساں پیکیج، پن سے پن مطابقت پذیر۔ مختلف پیکیج والے پرزے جن کے لیے PCB دوبارہ کام درکار ہو، شامل نہیں ہیں۔
اس سیریز میں مختلف ورژن
اسی سیریز کے ماڈلز جو ڈراپ اِن مطابقت رکھتے ہیں MAX1295BCEI (یکساں فارم فیکٹر اور فٹ پرنٹ) — میں مختلف Package, Sampling Rate, Architecture, Resolution, Analog Input Range.
MAX1295BCEI+
✅ ڈراپ-اِن📋 حوالہ جاتی متبادل (کیٹلاگ میں نہیں)
MAX1295BCEI+T
✅ ڈراپ-اِن📋 حوالہ جاتی متبادل (کیٹلاگ میں نہیں)
MAX1294BCEI
✅ ڈراپ-اِنقیمت کے لیے رابطہ کریں
ڈیٹا شیٹ دیکھیں →MAX1294BCEI+
✅ ڈراپ-اِن📋 حوالہ جاتی متبادل (کیٹلاگ میں نہیں)
MAX1293BCEI
✅ ڈراپ-اِن📋 حوالہ جاتی متبادل (کیٹلاگ میں نہیں)
MAX1295BCEI زیادہ سے زیادہ ریٹنگز اور برقی خصوصیات
| ریزولوشن | 12 bits |
| سیمپلنگ ریٹ | 265 ksps |
| Number of Input Channels | 6 single-ended / 3 pseudo-differential (MAX1295) |
| سپلائی وولٹیج | +3 V (single supply, +2.7 V to +3.6 V) |
| Integral Nonlinearity (INL) | ±0.5 LSB (max) |
| Differential Nonlinearity (DNL) | ±0.5 LSB (max) |
| Architecture | Successive Approximation (SAR) with input T/H |
| Internal Reference | +2.5 V |
| External Reference Support | Yes (REF pin accepts external reference) |
| Digital Interface | Parallel (byte/word) |
| Power-Down Current | 1 µA (typ) |
| Analog Input Range | 0 V to VREF (single-ended) |
| پیکیج | 28-pin SSOP / QSOP |
| ماؤنٹنگ ٹائپ | Surface Mount |
| RoHS اسٹیٹس | Compliant (variants with + suffix) |
MAX1295BCEI پن کنفیگریشن
| پن 1 | AIN0 — Analog input channel 0 |
| پن 2 | AIN1 — Analog input channel 1 |
| پن 3 | AIN2 — Analog input channel 2 |
| پن 4 | AIN3 — Analog input channel 3 |
| پن 5 | AIN4 — Analog input channel 4 |
| پن 6 | AIN5 — Analog input channel 5 |
| پن 7 | REF — Reference input/output (internal +2.5V) - bypass with 0.1µF + 10µF |
| پن 8 | REFADJ — Reference adjust / external reference input |
| پن 9 | AGND — Analog ground |
| پن 10 | AVDD — Analog +3V supply |
| پن 11 | DVDD — Digital +3V supply |
| پن 12 | DGND — Digital ground |
| پن 13 | CS — Chip-select (active-low) |
| پن 14 | WR — Write (active-low) |
| پن 15 | RD — Read (active-low) |
| پن 16 | D0/D8 — Data bit 0 (or bit 8 in word mode) |
| پن 17 | D1/D9 — Data bit 1 (or bit 9 in word mode) |
| پن 18 | D2/D10 — Data bit 2 (or bit 10 in word mode) |
| پن 19 | D3/D11 — Data bit 3 (or bit 11 in word mode) |
| پن 20 | D4 — Data bit 4 |
| پن 21 | D5 — Data bit 5 |
| پن 22 | D6 — Data bit 6 |
| پن 23 | D7 — Data bit 7 |
| پن 24 | HBEN — High-byte enable for word reads |
| پن 25 | INT/RDY — Interrupt / conversion-ready output (active-low) |
| پن 26 | PD — Power-down input (active-high) |
| پن 27 | SHDN — Software shutdown control |
| پن 28 | NC — Not connected (per datasheet) |
عام استعمالات
MAX1295BCEI کے لیے موزوں ہے 6 ایپلیکیشنs: Industrial Multi-Channel Data Acquisition, Portable Battery-Powered Instrumentation, System Monitoring and Housekeeping, Motor Control Current and Voltage Feedback, Process Control Sensor Interface, Medical Patient Monitoring Front End.
Industrial Multi-Channel Data Acquisition
The MAX1295BCEI's 6 single-ended / 3 pseudo-differential analog inputs and 12-bit/265ksps SAR throughput make it a natural fit for industrial data-acquisition front-ends where multiple sensors (thermistors, RTDs, 4-20 mA shunts) must be sampled at deterministic intervals. Placed behind sensor signal-conditioning op-amps, the ADC digitises each channel and outputs the conversion result on the parallel bus directly to the host CPU in a single read cycle, eliminating the firmware overhead of a serial interface. The internal +2.5V reference keeps the analog chain simple, while external reference override allows ratiometric measurements when paired with bridge sensors powered from VREF. Compared with a 16-bit SAR, the 12-bit/265ksps combination reduces system cost by 40-60% while still providing 0.024% FSR resolution, sufficient for closed-loop process control.
تجویز کردہ
Portable Battery-Powered Instrumentation
Battery-powered handheld meters and portable test instruments benefit from the MAX1295BCEI's auto-shutdown mode (typical 1 µA between conversions) and moderate 1.7 mA active supply current. The 6-channel multiplexer lets one ADC replace six individual single-channel parts, reducing PCB area and BOM cost, while the internal +2.5V reference eliminates the need for a separate reference IC. Designers typically place the device behind a low-power op-amp buffer (such as the MAX4475) and switch the system in and out of conversion quickly via the hardware power-down pin, achieving average supply currents below 100 µA in slow-logging applications. Compared with continuous-conversion ADCs, this part offers a 50-100× reduction in idle current, extending battery life in field-deployed sensor loggers.
تجویز کردہ
System Monitoring and Housekeeping
Server, networking, and telecom hardware designs frequently require a housekeeping ADC to monitor supply rails, temperature, fan tach, and chassis status. The MAX1295BCEI's 6 single-ended inputs and parallel host interface are well-matched to this role: one IC digitises PSU rails (3.3V, 5V, 12V via resistor dividers), board temperature via onboard diode or thermistor, and up to three additional analog housekeeping channels, with the result read by the BMC or management MCU over its parallel bus in a single access. Auto power-down between scans keeps the housekeeping ADC effectively free in standby, and the integrated +2.5V reference avoids tying up an external reference. Compared with discrete ADCs, the 28-QSOP footprint and integrated mux deliver a complete board-monitoring front end in 4.9 mm × 9.9 mm of PCB area.
تجویز کردہ
Motor Control Current and Voltage Feedback
In motor-control and power-conversion designs, the MAX1295BCEI provides a parallel-interface ADC for phase-current sense, DC-bus voltage and temperature sensing with a single +3V supply rail shared with the DSP or MCU. Each conversion completes in 3.8 µs at 265 ksps, fast enough to sample the controller current loop at well above the PWM frequency. The pseudo-differential mode allows direct digitisation of shunt-current sense amplifiers with common-mode voltages up to ±VREF, eliminating an instrumentation front stage. Compared with external dedicated motor-control ADCs, this part's integrated multiplexer lets one ADC monitor three motor phases plus three auxiliary signals (DC bus, temperature, fault) on a single chip, reducing BOM cost and PCB area in cost-sensitive BLDC and PMSM drives.
تجویز کردہ
Process Control Sensor Interface
Process-control systems in chemical, oil-and-gas, and water-treatment plants require rugged multi-channel analog front-ends that interface 4-20 mA loops, thermocouples and RTDs to digital controllers. The MAX1295BCEI's 6 single-ended / 3 pseudo-differential channel mux and 12-bit resolution deliver 0.024% FSR accuracy, sufficient for trend logging and threshold alarming in supervisory loops where cost matters more than 16-bit precision. Placed after the 4-20 mA receiver resistor and an isolated analog front end, the ADC provides a digital readout to the PLC via its parallel interface. Compared with 16-bit sigma-delta ADCs, this 12-bit SAR device draws half the supply current and costs 30-50% less, well-matched to large-scale process I/O modules.
تجویز کردہ
Medical Patient Monitoring Front End
In medical monitoring equipment (vital-signs monitors, ambulatory recorders, infusion pumps), the MAX1295BCEI digitises multiple analog sensor channels - ECG, SpO2, respiration, temperature, battery voltage - with a single chip and +3V supply. The internal +2.5V reference simplifies ratiometric measurement of bridge-style sensors, while the 12-bit resolution (610 µV LSB) provides adequate dynamic range for physiological signals after analog gain. Power-down between conversions lets battery-powered ambulatory devices sleep most of the time, helping achieve 24-72 hour battery life targets. Designers should add the MAX1295BEEI variant (extended -40°C to +85°C) for non-clinical-temperature environments, and choose this part in 28-QSOP package for compact handheld form factors.
تجویز کردہ
تجویز کردہ پروڈکٹس کا خلاصہ
کے لیے انجینئرنگ ریفرنس ڈیٹا MAX1295BCEI — موازنہ، ڈیزائن رہنمائی، اور تعمیل کی معلومات۔
انتخاب کی گائیڈ
متبادلات کے ساتھ موازنہ
| پیرامیٹر | یہ پروڈکٹ | MAX1295BCEI+ | MAX1295BCEI+T | MAX1294BCEI | MAX1294BCEI+ | MAX1293BCEI |
|---|---|---|---|---|---|---|
| Brand | Analog Devices (Maxim Integrated) | Analog Devices (Maxim Integrated) | Analog Devices (Maxim Integrated) | Analog Devices (Maxim Integrated) | Analog Devices (Maxim Integrated) | Analog Devices (Maxim Integrated) |
| Package | 28-QSOP | 28-QSOP | 28-QSOP | 28-QSOP | 28-QSOP | 28-QSOP |
| Resolution | 12 bits | 12 bits | 12 bits | 12 bits | 12 bits | 12 bits |
| Sampling Rate | 265 ksps | 265 ksps | 265 ksps | 265 ksps | 265 ksps | 265 ksps |
| Input Channels (single-ended) | 6 | 6 | 6 | 8 | 8 | 4 |
| Pseudo-Differential Channels | 3 | 3 | 3 | 4 | 4 | 2 |
| Internal Reference | +2.5 V | +2.5 V | +2.5 V | +2.5 V | +2.5 V | +2.5 V |
| Supply Voltage | +3 V | +3 V | +3 V | +3 V | +3 V | +3 V |
| Interface | Parallel | Parallel | Parallel | Parallel | Parallel | Parallel |
اہم امتیازی خصوصیات
- Lowest-cost 6-channel SAR ADC with internal reference in the MAX129x family (بمقابلہMAX1294BCEI)
- Drop-in RoHS-compliant version available from same factory (بمقابلہMAX1295BCEI+)
- Auto power-down to 1 µA between conversions (بمقابلہMAX1294BCEI)
ڈیزائن نوٹس
Place a 0.1 µF ceramic decoupling capacitor within 5 mm of the AVDD and DVDD pins, paired with a 10 µF tantalum or ceramic bulk capacitor on the same supply rail. Separating analog and digital supplies - even when both come from the same +3V LDO - with a ferrite bead or small L-C filter reduces digital switching noise coupling into the SAR comparator. The internal +2.5V reference must also be bypassed with 0.1 µF + 10 µF at the REF pin; failure to do so can degrade INL by 0.5-1 LSB at high source impedances.
Do not leave the unused analog inputs AIN0-AIN5 floating when not in use - tie unused inputs to AGND or mid-scale VREF via 10 kΩ resistors to prevent the input track-and-hold from drifting into saturation. Driving inputs outside 0 V to VREF will forward-bias the ESD protection diodes and inject current into AVDD, which can cause conversion errors or latch-up. With a parallel host bus running at 100 ns access time, also ensure that the WR/RD signals are properly synchronised - a missed write pulse leaves the channel register in an undefined state until the next valid write.
Estimated: route the parallel data bus (D0-D7) on a single inner layer adjacent to a contiguous DGND plane, keeping trace lengths matched within ±5 mm to avoid timing skew on read cycles. Keep the analog input traces short (≤10 mm) and surrounded by AGND ground pour on both sides to maximise common-mode rejection. Place the REFADJ pin component close to the device to avoid picking up digital switching noise. Mount the decoupling network so that the ceramic cap leads land directly into a wide power-supply copper pour rather than a thin trace.
تعمیل کی معلومات
Compliance status of the bare MAX1295BCEI (without '+' suffix) was not explicit in the verified web data; the 'plus' variant MAX1295BCEI+ is RoHS-compliant lead-free per Maxim/Analog Devices. AEC-Q100 not applicable for this ADC. REACH and conflict-minerals compliance inferred from Maxim Integrated standard policy.
