MAX165ACWN+ - 5µs 8-Bit ADC w/ T/H + Reference | Maxim
MPN: MAX165ACWN+ ⚠ Last Time Buy| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $12.5 | $12.50 |
| 10 | $11.2 | $112.00 |
| 100 | $9.85 | $985.00 |
| 500 | $8.65 | $4,325.00 |
| 1,000 | $7.4 | $7,400.00 |
MAX165ACWN+ Overview
An 8-bit ADC is the lowest-resolution member of the successive-approximation family and is typically chosen when conversion latency and BOM cost dominate the design rather than dynamic range. Within the data-converter hierarchy, this device sits as: ADC -> SAR ADC -> 8-bit precision ADC -> data converter -> signal chain IC -> integrated circuit. The internal 2.46 V reference gives a 0–2.46 V analog input range by default, but the reference can be overdriven to extend the input span to 0–VD for higher-voltage signals.
Key specifications include 5 µs conversion time, 8-bit resolution with ±½ LSB linearity, single +5 V supply operation, internal 2.46 V reference, on-chip track-and-hold, and a ratiometric conversion mode that cancels reference drift. The 18-pin SOIC (Wide) package provides 18 gull-wing leads suitable for standard surface-mount assembly. Typical operating power is around 7 mW at 5 V, making the part well-suited to battery-instrumented designs and embedded controllers. The MAX165ACWN+ is the commercial-temperature (0 °C to +70 °C) variant; the MAX165AEWN+ offers the -40 °C to +85 °C extended industrial grade.
The MAX165ACWN+ uses a switched-capacitor SAR architecture followed by a CMOS DAC; the track-and-hold acquires the analog input during the first clock cycles and holds it constant while the SAR determines the bit pattern. The internal reference is a buried Zener with a low-temperature coefficient; the reference buffer can source/sink the dynamic currents demanded by the DAC without distorting the reference node. Ratiometric conversion is supported by tying REF low and applying a full-scale voltage directly to the AIN pin.
Typical applications include digital panel meters, process-control front-ends, portable data loggers, battery chargers with current monitoring, and any microcontroller- or microprocessor-based system requiring an 8-bit analog front-end. The parallel interface maps cleanly onto 8051, PIC, and ARM Cortex-M data buses via simple glue logic or a single I/O port.
When designing with this part, observe the manufacturer's acquisition-time recommendations in the AC Electrical Characteristics table and place the analog input bypass capacitor as close as possible to the AIN pin to avoid kickback-induced error. Note that the MAX165ACWN+ is no longer in active production — the CWN commercial-temperature variant is approaching end-of-life, while the MAX165BEWN+ and A/E temperature-grade variants remain active for new designs.
This page synthesizes distributor pricing, drop-in same-package alternatives (MAX165BCWN+, MAX165BEWN+, MAX165AEWN+), and practical design notes not found in the manufacturer datasheet alone.
Drop-in alternatives for MAX165ACWN+ — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Variants in this series
Same-series models that are drop-in compatible with MAX165ACWN+ (same form factor and footprint) — differing in Conversion Time, Input Voltage Range, Operating Temperature, Package, Data Interface.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
MAX165BCWN+
✅ Drop-In📋 Reference alternative (not in catalog)
MAX165BEWN+
✅ Drop-In📋 Reference alternative (not in catalog)
MAX165AEWN+
✅ Drop-In📋 Reference alternative (not in catalog)
MAX165ACWN+T
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
MAX165BCWN
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
$12.4 / Unit
View Datasheet →MAX165ACWN+ Maximum Ratings & Electrical Characteristics
| Resolution | 8 bit |
| Conversion Method | SAR (Successive Approximation) |
| Number of Inputs | 1 |
| Conversion Time | 5 µs (max) |
| Input Voltage Range | 0 V to 2.46 V (or 0 to VDD ratiometric) |
| Internal Reference Voltage | 2.46 V |
| Reference Type | Internal (external overdrive supported) |
| Supply Voltage | +5 V (single supply) |
| Supply Current (typical) | 1.4 mA |
| Power Dissipation (typical) | 7 mW at 5 V |
| Track-and-Hold | Yes (on-chip) |
| Interface | Parallel, µP-compatible |
| Linearity (INL/DNL) | ±½ LSB (max) |
| Operating Temperature | 0 °C to +70 °C (commercial, CWN grade) |
| Package | 18-pin SOIC (Wide) |
| Mounting Type | Surface Mount |
MAX165ACWN+ Pin Configuration
| Pin 1 | VIN+ — Analog input positive |
| Pin 2 | VIN- — Analog input negative / signal ground |
| Pin 3 | REF — Reference voltage input/output (2.46 V internal) |
| Pin 4 | AGND — Analog ground |
| Pin 5 | DB0 — Data bit 0 (LSB) |
| Pin 6 | DB1 — Data bit 1 |
| Pin 7 | DB2 — Data bit 2 |
| Pin 8 | DB3 — Data bit 3 |
| Pin 9 | DB4 — Data bit 4 |
| Pin 10 | DB5 — Data bit 5 |
| Pin 11 | DB6 — Data bit 6 |
| Pin 12 | DB7 — Data bit 7 (MSB) |
| Pin 13 | CS — Chip select (active low) |
| Pin 14 | RD — Read strobe (active low) |
| Pin 15 | DGND — Digital ground |
| Pin 16 | VDD — +5 V supply |
| Pin 17 | CLK — Conversion clock input |
| Pin 18 | INT — Interrupt / end-of-conversion output (active low) |
Typical Applications
MAX165ACWN+ is suitable for 6 applications: Digital Panel Meter Front-End, Process Control Analog Input Module, Portable Data Logger Front-End, Battery Charger Current Monitor, Embedded Microprocessor Analog Front-End, Load Cell / Bridge Sensor Digitizer.
Digital Panel Meter Front-End
The MAX165ACWN+'s 8-bit resolution and 0–2.46 V input range make it a direct fit for 3½-digit digital panel meters measuring 0–200 mV or 0–2 V signals. Its 5 µs conversion enables 100 kHz effective sample rates for fast-update panel displays, and the internal reference and on-chip track-and-hold reduce the BOM to a single bypass capacitor and the ADC. When the panel meter is built around a PIC or 8051 microcontroller, the parallel interface maps cleanly onto a single 8-bit port, and ratiometric mode lets a precision resistor-divider drive AIN for direct ohms measurement.
Recommended
Process Control Analog Input Module
In a 4–20 mA or 0–10 V process-control input module, the MAX165ACWN+ digitizes the conditioned analog signal with ±½ LSB linearity, more than adequate for 8-bit PLC and DCS analog input cards. The internal 2.46 V reference accepts a resistor-divider-scaled 0–10 V input directly when overdriven, eliminating a separate reference IC. The CMOS low-power core (7 mW typical) suits DIN-rail-mounted modules with shared +24 V / +5 V rails, and the 18-pin SOIC footprint allows compact multi-channel modules where eight MAX165ACADC packages share a single 8051 data bus via address decoding.
Recommended
Portable Data Logger Front-End
Battery-powered portable data loggers use the MAX165ACWN+ because its 7 mW typical power dissipation extends operating time on a single 9 V battery or two AA cells. The internal reference and track-and-hold eliminate two of the largest quiescent-current external components, keeping total analog-front-end current under 10 mW — compatible with HIL and HMI handheld instruments. The 5 µs conversion supports burst-mode sampling of thermocouple or thermistor-divider inputs, with ratiometric conversion canceling supply-ratiometric drift as the battery discharges during long log sessions.
Recommended
Battery Charger Current Monitor
The MAX165ACWN+ is well-suited for closed-loop battery-charger current monitoring because its 8-bit resolution and 5 µs conversion time support 100 kHz PWM-synchronized current sampling for average-current-mode control. The on-chip reference and track-and-hold allow the current-sense amplifier output to be connected directly to AIN, with no external sample-and-hold needed for high-side or low-side shunt monitoring. The CMOS SAR core operates from a single +5 V rail shared with the microcontroller supervisor, simplifying the charger analog chain.
Recommended
Embedded Microprocessor Analog Front-End
When paired with an 8051, PIC16/PIC18, or ARM Cortex-M0 microcontroller, the MAX165ACWN+ provides a parallel 8-bit interface that maps onto a single GPIO port with no glue logic, allowing software-driven ADC reads via a single MOVX instruction. The 5 µs conversion time keeps the CPU free for other tasks at typical control-loop rates of 1–10 kHz. The internal reference and track-and-hold mean the firmware engineer only needs to issue a start-of-conversion pulse and read the parallel data lines, making the MAX165ACWN+ one of the simplest 8-bit ADC interfaces for any 8-bit or 32-bit MCU family.
Recommended
Load Cell / Bridge Sensor Digitizer
For load cell, strain-gauge, and Wheatstone-bridge sensors, the MAX165ACWN+ supports ratiometric conversion by tying REF low and applying the bridge excitation voltage directly to AIN, which cancels bridge excitation drift and produces a true ratio-metric output. The on-chip track-and-hold samples the bridge output cleanly during each conversion, eliminating the analog ground noise that would otherwise alias into a separate S/H stage. This configuration is standard for digital scales, force-sensing joysticks, and pressure-transducer digitizers where 8-bit resolution is sufficient for the measurement span.
Recommended
Recommended Products Summary
Engineering reference data for MAX165ACWN+ — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | MAX165BCWN+ | MAX165BEWN+ | MAX165AEWN+ | MAX165ACWN+T | MAX165BCWN |
|---|---|---|---|---|---|---|
| Brand | Maxim Integrated | Maxim Integrated | Maxim Integrated | Maxim Integrated | Maxim Integrated | Maxim Integrated |
| Package | 18-pin SOIC (Wide) | 18-pin SOIC (Wide) - same | 18-pin SOIC (Wide) - same | 18-pin SOIC (Wide) - same | 18-pin SOIC (Wide) - same | 18-pin SOIC (Wide) - same |
| Resolution | 8 bit | 8 bit | 8 bit | 8 bit | 8 bit | 8 bit |
| Conversion Time | 5 µs | 5 µs | 5 µs | 5 µs | 5 µs | 5 µs |
| Internal Reference | 2.46 V | 2.46 V | 2.46 V | 2.46 V | 2.46 V | 2.46 V |
| Operating Temperature | 0 °C to +70 °C (CWN commercial) | 0 °C to +70 °C | -40 °C to +85 °C | -40 °C to +85 °C | 0 °C to +70 °C | 0 °C to +70 °C |
| Production Status (2026-10-14) | Last-time-buy | Active | Active | Active | Last-time-buy | Active |
Key Differentiators
- Integrated reference and track-and-hold reduce BOM (vs ADC0804 (legacy National Semi 8-bit ADC))
- 5 µs conversion — 20× faster than ADC0804 (vs ADC0804 (legacy 100 µs 8-bit ADC))
- Same-package drop-in upgrade path to active-production parts (vs MAX165BCWN+ / MAX165BEWN+ (active variants))
Design Notes
The MAX165ACWN+ draws about 1.4 mA typical supply current at 5 V. Decouple VDD with a 0.1 µF ceramic capacitor placed within 5 mm of pin 16, and add a 10 µF bulk tantalum or ceramic capacitor on the same +5 V rail. Analog and digital grounds should be tied at a single point near the ADC AGND pin (pin 4) to avoid ground-loop noise injection into the SAR comparator. Avoid sharing the ADC's analog supply with high-current digital loads.
Source impedance at AIN (pin 1) should be kept below 5 kΩ to ensure the internal track-and-hold settles within the 5 µs acquisition window. For higher source impedances, add an input buffer such as the MAX4238 or MCP6002 between the source and AIN to maintain INL within ±½ LSB. Place the analog input bypass capacitor as close as possible to pin 1 and route the AIN trace away from digital data-bus lines to minimize crosstalk.
Use a 4-layer PCB with a dedicated ground plane for the analog section beneath the MAX165ACWN+. Keep the 18-SOIC footprint on the analog side of the board and route the DB0–DB7 parallel bus over the digital side, with vias clustered near the processor data port. If the design uses ratiometric conversion with a bridge sensor, place the bridge completion resistors and AIN bypass cap within 10 mm of pins 1 and 2 to minimize thermocouple-induced offset drift.
Do not leave the CS pin floating — it must be driven low to enable a read. Forgetting to assert CS before reading DB0–DB7 will leave the data bus in a high-impedance state and produce bus-contention on shared data lines. Also, do not exceed VDD on AIN or REF; over-voltage on the analog input can permanently damage the ESD cell. For designs migrating from ADC0804, note that the MAX165ACWN+ requires an external clock on the CLK pin rather than the internal RC oscillator found on ADC0804.
Compliance Information
RoHS / REACH / lead-free / halogen-free status not present in the verified distributor data — set to 'unknown' pending a manufacturer declaration. AEC-Q100 is not_applicable because the part is an 8-bit ADC for industrial/commercial signal-chain use, not an automotive-qualified part.
