MAX1246BCEE - 12-Bit, 133ksps, 4-Ch SAR ADC | Maxim Integrated
MPN: MAX1246BCEE ✓ AktifMAX1246BCEE Ringkasan
A SAR ADC is a type of analog-to-digital converter that uses a binary search algorithm with an internal capacitive DAC and a comparator to resolve one bit per clock cycle, delivering deterministic latency and excellent DC accuracy without pipeline delay. SAR ADCs are widely favored for multiplexed multi-channel data acquisition systems where precise, low-noise measurements of slowly-changing sensor signals are required, occupying a position above general-purpose integrating ADCs and below higher-speed pipeline ADCs in the data-converter hierarchy.
Key specifications include ±1 LSB INL (B-grade), ±1 LSB DNL (no missing codes), an internal 2.048V reference, a hardware SHDN-bar pin plus software-controlled power-down that drops supply current to under 1 µA between conversions, and an external differential reference option. The MAX1246 family also provides automatic end-of-conversion shutdown for true micropower operation, making it well suited to battery-powered instrumentation.
The 16-QSOP pinout exposes AIN0–AIN3 (or AIN0/1+ and AIN2/3-), REF, REFADJ, SHDN-bar, CS-bar, SCLK, DOUT, and DGND/SGND. Hardware-programmable channel-count and reference mode pins allow the same silicon to be configured as 2-channel differential or 4-channel single-ended without software overhead.
Typical applications include portable data loggers, 4-20 mA loop-powered sensors, battery stack monitors, isolated transducer front ends, panel meters, and medical instrumentation front ends. For multi-rail designs needing more channels or higher speed, consider the MAX1230 family; for lower-power 8-channel needs, the MAX1247 is pin-compatible.
Designers should place 0.1 µF ceramic bypass close to VDD and REF, route AIN traces away from SCLK/DOUT, and use the SHDN-bar pin to gate conversions for sub-microamp idle current. Compared with the MAX1246AEEE+, the B-grade guarantees tighter ±1 LSB INL/DNL across the full operating range.
Alternatif penggantian untuk MAX1246BCEE — paket yang sama, pin-pada-pin kompatibel. Bagian paket yang berbeda memerlukan kerja ulang PCB diabaikan.
Variasi di dalam seri ini
Model-series yang sama yang kompatibel dengan penggantian MAX1246BCEE (sama faktor bentuk dan footprint) — berbeda di dalam Architecture, Input Type, Operating Temperature, Resolution.
MAX1246BCEE+T
✅ Drop-In📋 Alternatif referensi (tidak dalam katalog)
MAX1246ACEE+
✅ Drop-In📋 Alternatif referensi (tidak dalam katalog)
MAX1246AEEE+
✅ Drop-In📋 Alternatif referensi (tidak dalam katalog)
MAX1246AEEE+T
✅ Drop-In📋 Alternatif referensi (tidak dalam katalog)
MAX1247CEE+
✅ Drop-In📋 Alternatif referensi (tidak dalam katalog)
MAX1246BCEE Rating Maksimal & Karakteristik Listrik
| Resolusi | 12 bit |
| Laju Pengambilan Sampel | 133 ksps |
| Number of Input Channels | 2 differential / 4 single-ended |
| Input Type | Differential, Single-Ended |
| Tegangan Pemuat | +2.7 V to +3.6 V |
| Supply Current (full throughput) | 0.9 mA typ |
| Power Consumption | 2.7 mW at 133 ksps |
| Arus Menutup | < 1 µA |
| INL (B-grade) | ±1 LSB (max) |
| DNL (B-grade) | ±1 LSB (no missing codes) |
| Internal Reference | 2.048 V |
| Data Interface | SPI / QSPI / MICROWIRE-compatible serial |
| Configuration | MUX-S/H-ADC |
| Architecture | SAR |
| Paket | 16-pin QSOP |
| Suhu Kerja | 0°C to +70°C (commercial) |
| Status RoHS | Compliant |
Konfigurasi Pin MAX1246BCEE
| Pin produk 1 | AIN0 — Analog input channel 0 |
| Pin produk 2 | AIN1 — Analog input channel 1 |
| Pin produk 3 | AIN2 — Analog input channel 2 |
| Pin produk 4 | AIN3 — Analog input channel 3 |
| Pin produk 5 | SGND — Signal ground |
| Pin produk 6 | REFADJ — Reference adjust / external reference select |
| Pin produk 7 | REF — Reference bypass / external reference input |
| Pin produk 8 | VDD — Positive supply (+2.7 V to +3.6 V) |
| Pin produk 9 | SCLK — Serial clock input |
| Pin produk 10 | CS-bar — Active-low chip select |
| Pin produk 11 | DOUT — Serial data output |
| Pin produk 12 | SHDN-bar — Active-low hardware shutdown |
| Pin produk 13 | NC — Not connected (per datasheet) |
| Pin produk 14 | DGND — Digital ground |
| Pin produk 15 | NC — Not connected (per datasheet) |
| Pin produk 16 | NC — Not connected (per datasheet) |
Aplikasi Umum
MAX1246BCEE cocok untuk 6 aplikasis: Portable Data Loggers, 4-20 mA Loop-Powered Sensors, Battery Stack Monitors, Panel Meters and Digital Multimeters, Medical Instrumentation Front Ends, Industrial Isolated Transducer Front Ends.
Portable Data Loggers
The MAX1246BCEE is well suited for handheld 4-channel data loggers digitizing thermocouples, RTDs, and battery voltages. Its 12-bit resolution, ±1 LSB INL (B-grade), and 133 ksps throughput let it capture multi-sensor bursts without aliasing, while the integrated 4:1 MUX eliminates an external analog switch. At 2.7 mW full-speed power and <1 µA in shutdown, it lets the logger sleep for months on a single CR2032 cell. The SHDN-bar pin enables firmware to gate conversions, so the same silicon can also serve 2-wire loop-powered loggers.
Direkomendasikan
4-20 mA Loop-Powered Sensors
In 2-wire 4-20 mA loop transmitters the MAX1246BCEE digitizes the sensor bridge with a 12-bit, ±1 LSB DNL core while drawing only 2.7 mW. Its 2.7 V minimum supply lets it run directly off the 12-24 V loop after a small shunt regulator, and the internal 2.048 V reference is calibrated for ratiometric measurement of strain gauges and RTDs. SHDN-bar plus auto power-down between conversions keeps loop current budget under 3 mA, leaving the 4-20 mA signal range untouched for live transmission back to the PLC.
Direkomendasikan
Battery Stack Monitors
Battery-management boards for lithium-ion packs use the MAX1246BCEE to digitize per-cell voltages and pack current at 133 ksps with ±1 LSB DNL. The internal MUX accepts up to four cell-sense inputs without an external switch, simplifying the BMS BOM, while the 2.7 V minimum supply rides directly on the lowest cell rail. The SHDN-bar pin is asserted between cell scans so total quiescent draw drops below 1 µA, extending shelf life. Built-in internal reference also reduces external components in cost-sensitive BMS modules.
Direkomendasikan
Panel Meters and Digital Multimeters
Handheld digital multimeters and panel meters rely on the MAX1246BCEE for its 12-bit ±1 LSB INL B-grade accuracy and 4-channel muxed input. The internal 2.048 V reference allows direct measurement of low-voltage signals after a precision resistor divider, and the SPI-compatible serial interface is easy to drive from low-cost 8-bit microcontrollers. The <1 µA shutdown current extends battery life between measurements, and the QSOP-16 footprint is small enough for sub-100 mm² meter PCBs.
Direkomendasikan
Medical Instrumentation Front Ends
Patient monitors, infusion pumps, and portable diagnostic devices use the MAX1246BCEE to digitize sensor outputs from thermistors, pulse oximeters, and pressure transducers. The 12-bit B-grade INL/DNL guarantees clinical accuracy over the full commercial temperature range, and the 2.7 V minimum supply supports single-cell lithium or 2x alkaline operation. SPI/QSPI compatibility enables firmware to integrate cleanly with low-power ARM Cortex-M microcontrollers, and the <1 µA shutdown supports strict IEC 60601 idle-current budgets in battery-powered carts.
Direkomendasikan
Industrial Isolated Transducer Front Ends
Isolated current, voltage, and temperature transducers digitize on the field side with the MAX1246BCEE before crossing an isolation barrier. The QSOP-16 package fits inside the small transducer head, and the 12-bit ±1 LSB B-grade accuracy meets Class 0.5 metering requirements. SPI output drives an isolator such as a digital isolator or opto-coupler with minimal firmware overhead, and the integrated MUX handles up to four sense channels per chip. The 2.7-3.6 V supply is conveniently compatible with 3.3 V isolated rails.
Direkomendasikan
Ringkasan Produk Direkomendasikan
Data referensi engineering untuk MAX1246BCEE — pembandingan, panduan desain, dan informasi konformitas.
Panduan Pemilihan
Pembandingan dengan Alternatif
| Parameter Umum | Produk Ini | MAX1246BCEE+T | MAX1246ACEE+ | MAX1246AEEE+ | MAX1246AEEE+T | MAX1247CEE+ |
|---|---|---|---|---|---|---|
| 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 | 16-QSOP | 16-QSOP - same | 16-QSOP - same | 16-QSOP - same | 16-QSOP - same | 16-QSOP - same |
| Resolution | 12 bit | 12 bit | 12 bit | 12 bit | 12 bit | 12 bit |
| Sampling Rate | 133 ksps | 133 ksps | 133 ksps | 133 ksps | 133 ksps | 133 ksps |
| Input Channels (single-ended / differential) | 4 / 2 | 4 / 2 | 4 / 2 | 4 / 2 | 4 / 2 | 8 / 4 |
| DNL (no missing codes) | ±1 LSB | ±1 LSB | ±1 LSB | ±1 LSB | ±1 LSB | ±1 LSB |
| Supply Voltage | +2.7 V to +3.6 V | +2.7 V to +3.6 V | +2.7 V to +3.6 V | +2.7 V to +3.6 V | +2.7 V to +3.6 V | +2.7 V to +3.6 V |
| Internal Reference | 2.048 V | 2.048 V | 2.048 V | 2.048 V | 2.048 V | 2.048 V |
Diferensiator Kunci
- B-grade INL/DNL with no missing codes (vsMAX1246ACEE+)
- 4-channel internal MUX in QSOP-16 (vsMAX1247CEE+)
- Hardware SHDN-bar plus auto end-of-conversion power-down (vsMAX1246AEEE+)
Catatan Desain
Place a 0.1 µF X7R ceramic bypass capacitor within 5 mm of the VDD pin and a 10 µF tantalum or ceramic bulk capacitor at the board supply input. The MAX1246BCEE draws 0.9 mA typ at 133 ksps, so a small ferrite bead on the VDD trace improves noise rejection from upstream switching regulators. Use the SHDN-bar pin to gate conversions; pulling it low drops quiescent current below 1 µA per the datasheet, so battery-powered designs should idle in shutdown whenever idle.
Route AIN0-AIN3 traces symmetrically and away from SCLK/DOUT to avoid digital coupling. Use a star ground topology with SGND and DGND joined only at the ADC GND pins to prevent ground-loop noise from coupling into the reference. The QSOP-16 package has a 0.635 mm pitch, so use 0.20 mm/0.25 mm trace-and-space design rules and a continuous ground pour under the part to act as a guard ring for analog traces.
Do not leave REF un-bypassed: a 4.7 µF tantalum plus 0.1 µF ceramic on REF is required for low noise. Avoid applying analog inputs before VDD is stable; the part latches up if any AIN pin exceeds VDD + 0.3 V. When switching to external reference mode, drive REFADJ before CS-bar falling edge per datasheet timing. Finally, do not exceed the 133 ksps throughput even briefly - the internal S/H settling becomes the bottleneck above rated speed.
Informasi Konformitas
RoHS compliant and lead-free per Maxim/ADI material declaration. AEC-Q100 not applicable (commercial grade). For automotive applications, consult Maxim/ADI for available AEC-Q100 qualified SAR ADCs in the MAX11xx/MAX12xx families.
