The MAX127/MAX128 are multirange, 12-bit data acquisition systems (DAS) that require only a single +5V supply for operation, yet accept signals at their analog inputs that may span above the power-supply rail and below ground. These systems provide eight analog input channels that are independently software programmable for a variety of ranges: ±10V, ±5V, 0 to +10V, 0 to +5V for the MAX127; and ±VREF, ±VREF/2, 0 to +VREF, 0 to +VREF/2 for the MAX128. This range switching increases the effective dynamic range to 14 bits and provides the flexibility to interface 4–20mA, ±12V, and ±15V-powered sensors directly to a single +5V system. In addition, these converters are fault pro- tected to ±16.5V; a fault condition on any channel will not affect the conversion result of the selected channel. Other features include a 5MHz bandwidth track/hold, an 8ksps throughput rate, and the option of an internal 4.096V or external reference. The MAX127/MAX128 feature a 2-wire, I2C-compatible serial interface that allows communication among multi- ple devices using SDA and SCL lines. A hardware shutdown input (SHDN) and two software- programmable power-down modes (standby and full power-down) are provided for low-current shutdown between conversions. In standby mode, the reference- buffer remains active, eliminating start-up delays. The MAX127/MAX128 are available in 24-pin DIP or space-saving 28-pin SSOP packages.
The MAX127 and MAX128 provide eight analog input channels, selectable input ranges (+10 V, +5 V, 0‑VREF, VREF/2, etc.), and a 2‑wire I²C‑compatible serial interface for easy integration. They operate from a single +5 V supply, tolerate input voltages up to +16.5 V, and offer an internal 4.096 V reference or an external reference option.
Typical applications include data‑acquisition systems, industrial control, robotics, battery‑powered instruments, and medical devices. The devices feature low‑power shutdown modes, 8 ksps throughput, and detailed layout and grounding recommendations for optimal performance.
| Analog Input Channels | 8 |
|---|---|
| Sampling Rate | 8 ksps |
| Input Overvoltage Tolerance | +16.5 V |
| Reference Options | Internal 4.096 V or external reference |
| Supply Voltage (Vppb) | 4.75 V to 5.25 V |
Both devices provide eight independent analog input channels.
The devices can sample at up to 8 ksps.
The ADCs operate from a single +5 V supply, with Vppb specified as 4.75 V to 5.25 V.
Yes, the input multiplexer is tolerant up to +16.5 V overvoltage.