Renesas X9400YS24IT1

Overview

X9400YS24IT1 from Intersil is a quad digitally controlled potentiometer (XDCP™) integrating four independent 64-tap resistor arrays with SPI interface, nonvolatile data registers (DR0–DR3), and power-on wiper recall. It operates from 2.7V to 5.5V VCC, supports ±5V analog rails (V+/V−), and delivers 40Ω typical wiper resistance at 5V - used for precision voltage divider, gain/offset adjustment, and programmable biasing in mixed-signal systems.

For engineers reviewing the X9400YS24IT1 datasheet, X9400YS24IT1 pinout, X9400YS24IT1 application, or X9400YS24IT1 equivalent, key selection criteria include its 24-pin SOIC package, SPI-compatible serial control with HOLD/CS/WR protection, quad-channel nonvolatile storage (100-year retention, 100k endurance), and dual-rail analog operation (−5V to +5V) enabling bipolar signal conditioning.

Technical Context

The X9400YS24IT1 implements four independent 63-segment resistor arrays, each controlled by a volatile 6-bit Wiper Counter Register (WCR) decoded to select one of 64 tap points. Each array features dedicated VH/RH, VL/RL, and VW/RW terminals, supporting both three-terminal potentiometer and two-terminal variable resistor configurations.

Its SPI interface supports read/write/transfer operations across four nonvolatile 6-bit Data Registers per channel, with hardware write protection (WP pin), device addressing (A0/A1), and HOLD functionality for serial pause/resume. Power-up automatically loads DR0 into the WCR, ensuring deterministic startup behavior without host intervention.

Key Specifications

Pinout & Package

Package: 24-lead SOIC (300 mil), RoHS-compliant Pb-free plus anneal finish, M24.3 drawing.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar digitally controlled potentiometer applications.

Compared with AD5204BRUZ10 and MCP42050-I/P, the X9400YS24IT1 uniquely combines quad-channel 64-tap control, true bipolar analog operation (−5 V to +5 V), and nonvolatile DR storage - making it optimal for calibration-critical, dual-rail mixed-signal systems where deterministic power-up behavior and long-term setting retention are mandatory.

Availability

X9400YS24IT1 is available at Aetrix Electronics and suitable for industrial sensor calibration, medical instrument offset trimming, and audio level control requiring stable component supply and guaranteed long-term parametric consistency.

Supply support for X9400YS24IT1 includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Intersil Corporation is a precision analog and power management semiconductor company, now part of Renesas Electronics, with deep expertise in high-reliability mixed-signal ICs for industrial and infrastructure markets.

The X9400 family was designed specifically for digitally programmable analog signal conditioning - delivering nonvolatile, low-noise, and bipolar-capable potentiometer functionality in compact monolithic packages for calibration-critical applications.

FAQ

What is the maximum SPI clock frequency supported by the X9400YS24IT1?

The X9400YS24IT1 supports a maximum SPI clock frequency of 2.0 MHz, as specified in the AC timing section of the datasheet. This allows fast register updates while maintaining robust noise immunity in industrial environments. The device uses standard SPI mode 0 (CPOL = 0, CPHA = 0), with data latched on the rising edge of SCK and output valid on the falling edge. At 2 MHz, the minimum clock cycle time is 500 ns, and setup/hold times for all inputs are guaranteed at 50 ns.

Does the X9400YS24IT1 require external pull-up resistors on its SPI lines?

No, the X9400YS24IT1 does not require external pull-up resistors on SI, SCK, or CS - all digital inputs have CMOS-compatible thresholds and internal leakage is below 10 µA. However, SO is a push-pull output and should never be externally pulled; if multiple devices share the SO line (e.g., daisy-chained), an external tri-state buffer or open-drain configuration is required - but the X9400YS24IT1 itself does not need pull-ups for normal point-to-point SPI operation.

How does the HOLD pin function during an active SPI transaction on the X9400YS24IT1?

The HOLD pin on the X9400YS24IT1 pauses an ongoing SPI transaction without resetting the internal command state. To activate HOLD, the pin must be driven LOW while SCK is LOW; the device freezes all internal counters and retains the current instruction context. Resuming requires bringing HOLD HIGH while SCK remains LOW. This feature enables multi-master arbitration and allows microcontrollers to service higher-priority interrupts mid-transfer - a capability confirmed in the Pin Descriptions and Timing Diagrams sections of the X9400YS24IT1 datasheet.

Can the X9400YS24IT1 be used with a 3.3V-only system powering both VCC and analog rails?

No - the X9400YS24IT1 requires separate analog supplies V+ and V−, which must be within −5.5 V to +5.5 V relative to VSS, and cannot be tied directly to 3.3V VCC. For 3.3V digital systems, VCC may be 3.3V, but V+ and V− must be independently supplied (e.g., ±2.5V or 0V/+3.3V) to meet the absolute ratings. Attempting to tie V+ to VCC violates the "Voltage on V+ (referenced to VSS)" limit of +5.5V only when VCC is 5V; at 3.3V, V+ must still be ≤ +5.5V but is not constrained to match VCC.

What happens to the wiper position of the X9400YS24IT1 during a power interruption shorter than one second?

If VCC drops below 0.1V for less than one second, the X9400YS24IT1 may fail to perform reliable power-on wiper recall. The datasheet specifies that VCC must remain below 0.1V for more than one second before reapplying power to guarantee DR0 loading into the WCR. Shorter interruptions risk incomplete internal reset, resulting in undefined wiper position or failure to restore the last saved setting - making the X9400YS24IT1 unsuitable for brown-out conditions without external supervision circuitry.