MAX145BEPA - 12-Bit 108ksps 2-Ch Serial ADC | Maxim Integrated
MPN: MAX145BEPA ✓ NakahandaMAX145BEPA Ulas
A SAR (Successive Approximation Register) ADC is a type of analog-to-digital converter that uses a binary search algorithm through an internal DAC to digitize an analog input one bit at a time per clock cycle. SAR ADCs are prized for low latency (deterministic acquisition time), high accuracy at moderate sample rates, and the absence of pipeline delay, making them well-suited to multiplexed multi-channel data-acquisition systems, instrumentation, and process control.
Key features include two single-ended analog input channels (CH0, CH1) selected via software, an analog supply range of +2.7V to +5.25V, an external reference input (REF), and a low supply current that drops to microamp levels in power-down mode. The MAX145BEPA industrial-grade (-40C to +85C) PDIP package supports through-hole assembly and is fully RoHS compliant in the + variant (MAX145BEPA+).
Architecturally, the MAX145BEPA integrates an input sample-and-hold, an internal 12-bit DAC, a comparator, a successive-approximation register, and SPI-compatible digital I/O on a single CMOS die. The automatic power-down function between conversions reduces average supply current to a fraction of the active value, which is critical for battery-powered or energy-harvesting applications.
Typical applications include portable data loggers, industrial process-control front-ends, battery-powered instrumentation, sensor signal conditioning read-out, and handheld metering equipment where 12-bit resolution at up to 108 kilosamples per second is sufficient. When laying out a PCB, keep analog and digital grounds joined at a single point near the ADC GND pin to preserve the 12-bit accuracy across the full sample rate.
Mga alternatibo na pwedeng ilagay na MAX145BEPA — parehas na package, pin-to-pin na katugmang. Hindi kasama ang mga bahagi ng iba't-ibang package na nangangailangan ng pagpapaayos ng PCB.
Variante sa Seri na ito
Katulad na modelo sa serye na katugma sa pagpasok MAX145BEPA (parehas na form factor at footprint) — pagkakaiba sa Conversion Time, Input Type, Number of Channels, Operating Temperature Range, RoHS Status.
MAX145AEPA
✅ Drop-InMagkontak para sa presyo
Tingnan ang Datasheet →MAX145BEPA+
✅ Drop-In📋 Alternatibo na Reference (hindi sa katalogo)
MAX144BEPA
✅ Drop-In📋 Alternatibo na Reference (hindi sa katalogo)
MAX145BEPA Mga Pinakamataas na Rating at Electrical Characteristics
| Pangangasiwaan | 12 bits |
| Number of Channels | 2 (single-ended) |
| Sample Rate | 108 ksps |
| Conversion Time | 7.4 us (successive approximation) |
| Wake-Up Time from Power-Down | 2.5 us |
| Analog Supply Voltage | +2.7 V to +5.25 V |
| Digital Logic Supply | Same as analog supply (single supply) |
| Input Type | Single-ended, CH0 / CH1 |
| Reference Input | External (REF pin) |
| Serial Interface | 3-wire SPI / QSPI / MICROWIRE-compatible |
| Built-in Clock | Yes (internal) |
| Automatic Power-Down | Yes (between conversions) |
| Packhaging | 8-pin PDIP (through-hole) |
| Hanay ng Temperature na Operasyon | -40 C to +85 C (industrial) |
| Uri ng Pagpapasok | Through-Hole |
| Tindminan RoHS | Compliant (MAX145BEPA+ variant) |
Pin Configuration ng MAX145BEPA
| Pin 1 | VDD — Power supply (+2.7V to +5.25V) |
| Pin 2 | CH0 — Analog input channel 0 |
| Pin 3 | CH1 — Analog input channel 1 (MAX145 only) |
| Pin 4 | GND — Ground |
| Pin 5 | REF — External reference voltage input |
| Pin 6 | DOUT — Serial data output (SPI) |
| Pin 7 | CS — Chip select (active low) |
| Pin 8 | DIN/SCLK — Serial data in / serial clock (shared SPI input) |
Tipikal na mga Gamit
MAX145BEPA ay nararapat para sa 6 aplikasyons: Battery-Powered Data Logger, Industrial Process-Control Front-End, Handheld Metering & Test Equipment, Sensor Signal Conditioning Read-Out, Portable Medical Monitoring Devices, Automotive Sensor Read-Out (Non-Safety).
Battery-Powered Data Logger
The MAX145BEPA's 12-bit resolution and 108 ksps sample rate allow accurate digitization of slow analog sensor channels such as temperature, pressure and battery voltage in portable data-logging equipment. According to the MAX144/MAX145 datasheet, automatic power-down reduces active current to a few microamps between conversions, enabling months of operation from a single Li-ion or AA battery pack. With 2 multiplexed channels (CH0/CH1) and an external reference, the MAX145BEPA delivers sufficient dynamic range for sensor signal conditioning while keeping the BOM small.
Inirekomenda
Industrial Process-Control Front-End
In PLC analog input modules and process-control instrumentation, the MAX145BEPA digitizes 4-20 mA current-loop or 0-10V transducer signals with 12-bit accuracy at up to 108 ksps aggregate throughput. Its +2.7V to +5.25V single-supply operation tolerates 24V industrial rails after external signal conditioning, and its -40C to +85C industrial temperature grade covers factory-floor environments. The 3-wire SPI interface connects directly to host microcontrollers and PLC communication ASICs without external glue logic.
Inirekomenda
Handheld Metering & Test Equipment
The MAX145BEPA's small 8-pin PDIP footprint and low average supply current make it ideal for handheld multimeters, insulation testers and portable calibration instruments. According to the MAX144/MAX145 datasheet, the 2.5 microsecond wake-up from power-down enables continuous on-demand conversions triggered by the host microcontroller, while preserving battery life between measurement cycles. The 7.4 microsecond acquisition-to-conversion latency is fast enough to capture transient signals during automated test sequences.
Inirekomenda
Sensor Signal Conditioning Read-Out
For strain-gauge bridges, thermocouple amplifiers and other low-bandwidth sensor front-ends, the MAX145BEPA provides 12-bit resolution with low integral nonlinearity suitable for capturing sensor output voltages in the millivolt-to-5V range. Its external reference input allows scaling the ADC full-scale range to the sensor output swing, maximizing effective resolution. The 3-wire SPI/QSPI/MICROWIRE-compatible interface simplifies integration with common low-power MCUs and DSPs in embedded sensor nodes.
Inirekomenda
Portable Medical Monitoring Devices
The MAX145BEPA's combination of 12-bit resolution, 108 ksps capability, low power consumption and -40C to +85C temperature range suits battery-powered medical monitoring peripherals such as pulse-oximeter front-ends, blood-pressure monitor signal read-out, and bedside patient monitors requiring 1-2 analog channels. According to the datasheet, automatic power-down and 2.5 microsecond wake-up minimize average current draw, while the SPI interface enables direct connection to low-power MCUs typically used in medical device designs.
Inirekomenda
Automotive Sensor Read-Out (Non-Safety)
While the MAX145BEPA is not AEC-Q100 qualified, its -40C to +85C industrial temperature range and 5V supply tolerance suit non-safety automotive applications such as cabin climate sensor read-out, body-comfort modules and infotainment analog audio level sensing. The 8-pin PDIP package is preferred for prototyping and through-hole production runs in aftermarket automotive electronics. For safety-critical powertrain or ADAS applications requiring AEC-Q100, choose a qualified alternative.
Inirekomenda
Buod ng mga Inirekomendang Produkto
Impormasyon ng Talumpati sa Engineering for MAX145BEPA — ikabit, gabay sa disenyo, at impormasyon ng pagsunod sa kautusan.
Paunawang Hanapin
Ikabit sa Mga Alternatibo
| Parametro | Ito ang Producto | MAX145AEPA | MAX145BEPA+ | MAX144BEPA |
|---|---|---|---|---|
| Package | PDIP-8 | PDIP-8 - same | PDIP-8 - same | PDIP-8 - same |
| Brand | Maxim Integrated | Maxim Integrated - same | Maxim Integrated - same | Maxim Integrated - same |
| Resolution | 12 bits | 12 bits | 12 bits | 12 bits |
| Number of Channels | 2 (CH0, CH1) | 2 (CH0, CH1) | 2 (CH0, CH1) | 1 (CH0 only) |
| Sample Rate | 108 ksps | 108 ksps | 108 ksps | 108 ksps |
| Supply Voltage | +2.7V to +5.25V | +2.7V to +5.25V | +2.7V to +5.25V | +2.7V to +5.25V |
| INL/DNL Grade | Standard (B-grade) | A-grade (tighter linearity) | Standard (B-grade), RoHS | Standard (B-grade) |
| RoHS Compliance | Non-compliant (no + suffix) | Non-compliant (no + suffix) | RoHS-compliant (+ suffix) | Non-compliant (no + suffix) |
| Operating Temperature | -40C to +85C | -40C to +85C | -40C to +85C | -40C to +85C |
Pangunahing mga Pagkakaiba
- Same-die A-grade with tighter linearity, drop-in compatible (kumpara saMAX145AEPA)
- RoHS-compliant variant of the same die (kumpara saMAX145BEPA+)
- Compatible 1-channel variant when CH1 is not used (kumpara saMAX144BEPA)
Talaan ng Disenyo
Route analog (CH0, CH1, REF) and digital (DOUT, DIN/SCLK, CS) traces separately, and join analog and digital grounds at a single point - typically at the ADC GND pin or at the decoupling-capacitor ground. According to the MAX144/MAX145 datasheet reference layout, this star-ground topology preserves 12-bit accuracy at full 108 ksps by preventing digital switching currents from corrupting the analog input and reference voltages.
Place a 0.1 microfarate ceramic decoupling capacitor as close as possible to the VDD pin and a 10 microfarate bulk bypass capacitor at the board supply entry. According to the MAX144/MAX145 datasheet, the internal reference/sample-and-hold settling is sensitive to high-frequency VDD ripple - good bypassing ensures specified INL/DNL is achieved. For systems operating above 50 ksps continuous, add an additional 1 microfarate capacitor in parallel with the 0.1 microfarate.
Do not leave any unused analog input (e.g. CH1 on MAX145) floating - tie unused inputs to midscale or ground to prevent charge-injection crosstalk into the active channel. The REF pin must be driven by a low-impedance reference (or a 10 microfarate + 0.1 microfarate RC network) - never leave REF floating or the conversions will be invalid. The CS pin must be held low during the entire conversion to avoid losing synchronization.
Impormasyon ng Pagsunod sa Kautusan
Non-compliant for RoHS as the legacy MAX145BEPA lacks the + suffix. The MAX145BEPA+ variant is RoHS compliant and lead-free. Not AEC-Q100 qualified - not suitable for automotive safety-critical applications. Choose qualified parts (e.g. MAX11120ATI+T) for AEC-Q100 designs.
