Texas Instruments SCANSTA476TSD/NOPB

Overview

SCANSTA476TSD/NOPB from Texas Instruments is an 8-channel analog voltage monitor IC with IEEE 1149.1 (JTAG) interface, 12-bit successive-approximation ADC core, ±2 mV typical measurement accuracy at VDD = 5.5 V, and operation from +2.7 V to +5.5 V supply. It samples up to eight analog inputs (A0–A7) referenced to VREF for system health monitoring in server power rails and telecom equipment.

For engineers reviewing the SCANSTA476TSD/NOPB datasheet, SCANSTA476TSD/NOPB pinout, SCANSTA476TSD/NOPB application, or SCANSTA476TSD/NOPB equivalent, this page delivers verified technical context, JTAG-controlled analog sampling behavior, WSON-16 package layout, real-time voltage monitoring capability, and validated alternative options for embedded test infrastructure design.

Technical Context

The SCANSTA476TSD/NOPB integrates a 12-bit SAR ADC core with a dedicated JTAG TAP controller compliant to IEEE 1149.1. All analog input channels (A0–A7) share a single VREF reference input, enabling full-scale range of 0 V to VREF (≤ VDD). Measurement resolution is fixed at 12 bits with straight binary output coding.

JTAG instruction shift selects one analog channel (op-codes 40h–47h), followed by 12-bit data shift of the sampled result on TDO. Throughput supports up to 1 MSPS at 20 MHz TCK, with no external microcontroller required-leveraging existing JTAG infrastructure for debug and field service voltage verification.

Key Specifications

Pinout & Package

SCANSTA476TSD/NOPB uses a 16-pin WSON (NHQ) package measuring 5 mm × 5 mm × 0.8 mm with exposed thermal pad (DAP) on underside serving as primary GND connection. Pin 1 is located in quadrant Q1 per tape-and-reel orientation.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar analog voltage monitoring applications.

Compared with ADS7953IRHBT and INA226AIDGST, the SCANSTA476TSD/NOPB uniquely delivers 8-channel analog monitoring through a standardized JTAG port - reducing BOM count and eliminating firmware dependencies in legacy test environments where JTAG access is guaranteed but GPIO/SPI is unavailable.

Availability

SCANSTA476TSD/NOPB is available at Aetrix Electronics and suitable for server power integrity validation, telecom line card diagnostics, and medical imaging power audit applications requiring stable component supply across extended production lifecycles.

Supply support for SCANSTA476TSD/NOPB 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

Texas Instruments is a global semiconductor company headquartered in Dallas, Texas, designing and manufacturing analog, embedded processing, and digital signal processing technologies since 1930.

The SCANSTA476TSD/NOPB belongs to TI's IEEE 1149.1-compliant analog monitoring product line, developed specifically to extend boundary-scan infrastructure into analog domain verification for high-reliability computing and communications systems.

FAQ

What is the primary function of the SCANSTA476TSD/NOPB?

The SCANSTA476TSD/NOPB is an 8-channel analog voltage monitor IC with integrated 12-bit SAR ADC and IEEE 1149.1 (JTAG) interface. Its primary function is to enable JTAG-based sampling and verification of up to eight analog power supply or reference voltages - eliminating the need for external microcontrollers or dedicated ADC interfaces. The SCANSTA476TSD/NOPB operates from +2.7 V to +5.5 V and delivers ±2 mV typical measurement accuracy at full scale.

How does the SCANSTA476TSD/NOPB interface with a JTAG controller?

The SCANSTA476TSD/NOPB uses standard IEEE 1149.1 signals: TCK, TMS, TDI, TDO, and TRST. Channel selection is performed via 8-bit instruction shift (op-codes 40h–47h map to A0–A7); a subsequent 12-bit data shift returns the ADC result on TDO. The SCANSTA476TSD/NOPB requires no custom JTAG instructions - it operates fully within the standard TAP controller state machine and supports back-to-back or interleaved sampling.

What is the role of the VREF pin on the SCANSTA476TSD/NOPB?

The VREF pin on the SCANSTA476TSD/NOPB serves as the analog reference voltage for all eight input channels (A0–A7), defining the full-scale input range as 0 V to VREF. VREF must be ≤ VDD and should be sourced from a low-noise, well-bypassed point - not directly from VDD. The SCANSTA476TSD/NOPB achieves ±2 mV typical accuracy only when VREF is stable and properly decoupled with 0.1 µF and 1 µF capacitors placed within 1 cm of the pin.

Does the SCANSTA476TSD/NOPB require external components for basic operation?

Yes - the SCANSTA476TSD/NOPB requires external decoupling: two capacitors (0.1 µF and 1 µF monolithic) on VREF and two identical capacitors on each VDD pin (pins 1 and 3), all placed within 1 cm of their respective pins. The DAP (exposed thermal pad) must be connected to the PCB ground plane using at least four thermal vias. No external clock, reference, or conversion-start circuitry is needed - timing and control are handled entirely via JTAG.

What package type and footprint does the SCANSTA476TSD/NOPB use?

The SCANSTA476TSD/NOPB uses a 16-pin WSON (NHQ) package measuring 5 mm × 5 mm × 0.8 mm with an exposed thermal pad (DAP) on the underside. Pin 1 is located in quadrant Q1 per tape-and-reel orientation. The package has no leads; connections are made via bottom-side solder pads. This compact footprint supports high-density placement in space-constrained applications such as server DIMM modules and telecom line card ASIC power delivery networks.