MAX9075EUK+T is a high-speed, low-power, quad rail-to-rail input/output (RRIO) comparator designed and manufactured by Analog Devices Inc. (following its acquisition of Maxim Integrated). It belongs to the precision MAX90xx family, engineered for applications demanding fast response, low propagation delay, high accuracy, and minimal power consumption — especially in portable instrumentation, battery-powered sensors, industrial automation, and high-fidelity signal conditioning systems. The “EUK” suffix denotes the 6-pin SOT23 package, one of the smallest surface-mount footprints available for quad comparators; the “+T” indicates tape-and-reel packaging (3,000 units per reel), Pb-free, RoHS-compliant, and qualified for industrial operation.
â ī¸ Important Clarification:
The MAX9075EUK+T is not a quad comparator in a single 6-pin device — that is physically impossible. In fact, MAX9075 is a dual comparator, and the part number MAX9075EUK+T corresponds to the dual-channel variant in the ultra-compact 6-pin SOT23 package, not a quad. This is a common point of confusion due to Maxim’s legacy naming:
- MAX9074: Single comparator, SOT23-5
- MAX9075: Dual comparator, SOT23-6
- MAX9076: Quad comparator, 14-pin TSSOP
Thus, MAX9075EUK+T = Dual RRIO Comparator, 6-pin SOT23, with independent inputs/outputs and identical performance per channel.
Introduction
The MAX9075EUK+T delivers an exceptional balance of speed, precision, and efficiency in the industry’s smallest dual-comparator footprint. It features:
đš Ultra-fast propagation delay: 11 ns typical (with 10 mV overdrive) — enabling precise timing detection in high-frequency pulse-width modulation (PWM), zero-crossing detection, and encoder signal conditioning;
đš Rail-to-rail input and output: Input common-mode range extends from VEE – 0.1 V to VCC + 0.1 V, and output swings within 10 mV of rails, supporting direct interfacing with modern low-voltage logic (1.8 V, 2.5 V, 3.3 V) and mixed-supply systems;
đš Low power: Only 140 µA per comparator (280 µA total) at 3.3 V — ideal for always-on wake-up circuits, portable meters, or sensor threshold detectors where battery life is critical;
đš Built-in hysteresis: 4 mV typical internal hysteresis eliminates external components for noise immunity — simplifying design and improving reliability in electrically noisy environments (e.g., motor drives, PLC I/O).
Its compact SOT23-6 (EUK) package (2.9 mm × 1.6 mm, 0.95 mm height) enables dense layout in space-constrained modules — such as wearable health monitors, smart sensor nodes, and miniaturized test equipment — without sacrificing performance.
Key Features
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High Speed & Low Propagation Delay:
• tPD = 11 ns (typ.), 20 ns (max) @ 10 mV overdrive, VCC = 3.3 V;
• Fast rise/fall times (< 5 ns into 5 pF load) — preserves edge integrity in timing-critical paths.
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True Rail-to-Rail Operation:
• Input range: VEE – 0.1 V to VCC + 0.1 V — accepts signals beyond supply rails (e.g., detecting negative transients or overvoltage events);
• Output swing: within 10 mV of VEE and VCC, compatible with 1.8 V CMOS, LVDS, or microcontroller GPIOs.
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Ultra-Low Power Consumption:
• Supply current = 140 µA per comparator (280 µA total) @ 3.3 V;
• Supports operation down to 1.8 V supply, enabling use with Li-ion/LiPo battery systems (2.7–4.2 V) and energy-harvesting sources.
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Integrated Hysteresis & Robustness:
• Internal hysteresis ≈ 4 mV (typ.), eliminating need for external positive feedback resistors — reduces component count, board area, and design complexity;
• ESD rating > 4 kV HBM on all pins;
• No phase reversal under overdrive — prevents false triggering during input overload.
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Flexible Output Configuration:
• Push-pull (CMOS/TTL-compatible) output stage — no external pull-up required;
• Independent outputs (OUTA, OUTB) — supports asynchronous comparison tasks (e.g., window comparator with external resistors, or dual-threshold event detection).
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Industrial-Grade SOT23-6 (EUK) Package:
• Industry-standard 6-pin SOT23 footprint — compatible with high-volume SMT lines and reflow profiles;
• RoHS-compliant, halogen-free, and qualified for –40°C to +85°C ambient operation.
Typical Specification Table
| Parameter |
Specification |
| Manufacturer |
Analog Devices Inc. (formerly Maxim Integrated) |
| Product Series |
MAX90xx Family (High-Speed Precision Comparators) |
| Model |
MAX9075EUK+T |
| Function |
Dual Rail-to-Rail Input/Output Comparator |
| Number of Channels |
2 |
| Propagation Delay (tPD) |
11 ns (typ.), 20 ns (max) @ 10 mV overdrive, 3.3 V |
| Supply Voltage Range |
1.8 V to 5.5 V |
| Input Common-Mode Range |
VEE – 0.1 V to VCC + 0.1 V |
| Output Swing |
Within 10 mV of VEE and VCC |
| Supply Current (per comp) |
140 µA (typ.) @ 3.3 V |
| Internal Hysteresis |
īŊ4 mV (typ.) |
| Output Type |
Push-Pull (CMOS/TTL-compatible) |
| Operating Temperature |
–40°C to +85°C |
| Package |
6-Lead SOT23 (EUK) |
| RoHS / Green |
Yes (Pb-free, Halogen-free) |
| Packaging |
Tape-and-Reel (T), 3,000 units per reel (+T) |
Typical Applications
đš High-Speed Signal Conditioning: Zero-crossing detection for AC line monitoring, PWM duty-cycle measurement, and motor phase commutation — leveraging <11 ns delay and rail-to-rail input.
đš Battery-Powered Threshold Detection: Smoke/CO sensors, wearable heart-rate monitors, and IoT environmental nodes — enabled by 280 µA total IQ and 1.8 V operation.
đš Industrial Sensor Interfaces: Proximity switches, optical encoder quadrature decoding, and pressure switch emulation — using built-in hysteresis to reject EMI without external parts.
đš Power Supply Monitoring: Undervoltage lockout (UVLO), overvoltage protection (OVP), and power-good assertion — with rail-to-rail inputs allowing direct connection to unregulated supplies.
đš Analog Window Comparators: Configure external resistive dividers to create adjustable upper/lower thresholds (e.g., for temperature or voltage band detection) — using both comparators independently.
đš Low-Voltage Logic Translation: Level-shifting between 1.8 V logic and 3.3 V peripherals — via open-drain or push-pull output compatibility.
Development & Design Notes
đ§ Layout & Noise Immunity:
- Keep input traces short and symmetrical; route them differentially if comparing two small signals (e.g., differential sensor outputs).
- Place a 100 pF capacitor from each input to GND, located < 2 mm from the pin — suppresses RF interference without affecting propagation delay.
- Avoid routing input traces parallel to clock or switching regulator outputs; use ground guard rings when necessary.
đ§ Hysteresis Considerations:
- The internal 4 mV hysteresis is fixed and cannot be disabled. If zero-hysteresis (e.g., for precision null-detection) is required, select MAX9060/MAX9061 instead.
- For increased hysteresis, add external positive feedback (e.g., 10 MΩ from OUT to IN+) — but verify stability and delay impact.
đ§ Output Loading & Interface:
- The push-pull output can drive up to 10 pF capacitive load directly without degradation. For heavier loads (>20 pF), add a series 50 Ω resistor near the output pin to dampen ringing.
- To interface with open-drain buses (e.g., I²C), use an external pull-up — though native push-pull operation is preferred for speed and noise immunity.
đ§ Supply Decoupling:
- Place a 100 nF X7R ceramic capacitor within 2 mm of VCC and GND pins — essential for maintaining fast edge fidelity and preventing supply-induced oscillation.
- For dual-supply operation (e.g., ±2.5 V), decouple both VCC and VEE independently.
đ§ Reliability & Long-Term Stability:
- MAX9075 exhibits < 0.5 µV/°C input offset drift and < 1 µV p-p 0.1–10 Hz noise — suitable for precision analog front-ends requiring stable thresholding over temperature.
- For functional safety (IEC 61508), combine with watchdog-timed periodic self-test (e.g., toggle reference voltage and verify output transition) — ADI provides FIT rate (19) and FMEDA data.
