Passive Components Blog
No Result
View All Result
  • Home
  • NewsFilter
    • All
    • Aerospace & Defence
    • Antenna
    • Applications
    • Automotive
    • Capacitors
    • Circuit Protection Devices
    • electro-mechanical news
    • Filters
    • Fuses
    • Inductors
    • Industrial
    • Integrated Passives
    • inter-connect news
    • Market & Supply Chain
    • Market Insights
    • Medical
    • Modelling and Simulation
    • New Materials & Supply
    • New Technologies
    • Non-linear Passives
    • Oscillators
    • Passive Sensors News
    • Resistors
    • RF & Microwave
    • Telecommunication
    • Weekly Digest

    Advances in the Environmental Performance of Polymer Capacitors

    Vishay Releases DLA Tantalum Polymer Capacitors for Military and Aerospace

    Vishay Expanded Inductor Portfolio With More Than 2000 Stock Items 

    Paumanok Releases Capacitor Foils Market Report 2025-2030

    Modelithics Welcomes CapV as a Sponsoring MVP

    Wk 40 Electronics Supply Chain Digest

    Benefits of Tantalum Powder Stress–Strain Curve Evaluation vs Conventional Wet Test

    Electrolyte Selection and Performance in Supercapacitors

    Connector PCB Design Challenges

    Trending Tags

    • Ripple Current
    • RF
    • Leakage Current
    • Tantalum vs Ceramic
    • Snubber
    • Low ESR
    • Feedthrough
    • Derating
    • Dielectric Constant
    • New Products
    • Market Reports
  • VideoFilter
    • All
    • Antenna videos
    • Capacitor videos
    • Circuit Protection Video
    • Filter videos
    • Fuse videos
    • Inductor videos
    • Inter-Connect Video
    • Non-linear passives videos
    • Oscillator videos
    • Passive sensors videos
    • Resistor videos

    Connector PCB Design Challenges

    Efficient Power Converters: Duty Cycle vs Conduction Losses

    Ripple Steering in Coupled Inductors: SEPIC Case

    SEPIC Converter with Coupled and Uncoupled Inductors

    Coupled Inductors in SEPIC versus Flyback Converters

    Non-Linear MLCC Class II Capacitor Measurements Challenges

    Percolation Phenomenon and Reliability of Molded Power Inductors in DC/DC converters

    Root Causes and Effects of DC Bias and AC in Ceramic Capacitors

    How to Calculate the Output Capacitor for a Switching Power Supply

    Trending Tags

    • Capacitors explained
    • Inductors explained
    • Resistors explained
    • Filters explained
    • Application Video Guidelines
    • EMC
    • New Products
    • Ripple Current
    • Simulation
    • Tantalum vs Ceramic
  • Knowledge Blog
  • Suppliers
    • Who is Who
  • Events
  • Home
  • NewsFilter
    • All
    • Aerospace & Defence
    • Antenna
    • Applications
    • Automotive
    • Capacitors
    • Circuit Protection Devices
    • electro-mechanical news
    • Filters
    • Fuses
    • Inductors
    • Industrial
    • Integrated Passives
    • inter-connect news
    • Market & Supply Chain
    • Market Insights
    • Medical
    • Modelling and Simulation
    • New Materials & Supply
    • New Technologies
    • Non-linear Passives
    • Oscillators
    • Passive Sensors News
    • Resistors
    • RF & Microwave
    • Telecommunication
    • Weekly Digest

    Advances in the Environmental Performance of Polymer Capacitors

    Vishay Releases DLA Tantalum Polymer Capacitors for Military and Aerospace

    Vishay Expanded Inductor Portfolio With More Than 2000 Stock Items 

    Paumanok Releases Capacitor Foils Market Report 2025-2030

    Modelithics Welcomes CapV as a Sponsoring MVP

    Wk 40 Electronics Supply Chain Digest

    Benefits of Tantalum Powder Stress–Strain Curve Evaluation vs Conventional Wet Test

    Electrolyte Selection and Performance in Supercapacitors

    Connector PCB Design Challenges

    Trending Tags

    • Ripple Current
    • RF
    • Leakage Current
    • Tantalum vs Ceramic
    • Snubber
    • Low ESR
    • Feedthrough
    • Derating
    • Dielectric Constant
    • New Products
    • Market Reports
  • VideoFilter
    • All
    • Antenna videos
    • Capacitor videos
    • Circuit Protection Video
    • Filter videos
    • Fuse videos
    • Inductor videos
    • Inter-Connect Video
    • Non-linear passives videos
    • Oscillator videos
    • Passive sensors videos
    • Resistor videos

    Connector PCB Design Challenges

    Efficient Power Converters: Duty Cycle vs Conduction Losses

    Ripple Steering in Coupled Inductors: SEPIC Case

    SEPIC Converter with Coupled and Uncoupled Inductors

    Coupled Inductors in SEPIC versus Flyback Converters

    Non-Linear MLCC Class II Capacitor Measurements Challenges

    Percolation Phenomenon and Reliability of Molded Power Inductors in DC/DC converters

    Root Causes and Effects of DC Bias and AC in Ceramic Capacitors

    How to Calculate the Output Capacitor for a Switching Power Supply

    Trending Tags

    • Capacitors explained
    • Inductors explained
    • Resistors explained
    • Filters explained
    • Application Video Guidelines
    • EMC
    • New Products
    • Ripple Current
    • Simulation
    • Tantalum vs Ceramic
  • Knowledge Blog
  • Suppliers
    • Who is Who
  • Events
No Result
View All Result
Passive Components Blog
No Result
View All Result

STMicro’s Newest Stepper Motor Driver: A 256-Microstep Driver with Integrated Control Logic Needs Precise Sense Resistors

24.4.2020
Reading Time: 4 mins read
A A

source: All about circuits article

STMicroelectronics offers their new microstepping motor driver that includes control logic and a power stage. Two precise sense resistors play an important role in the PWM current control—for both slow decay and mixed decay current recirculation conditions

RelatedPosts

Advances in the Environmental Performance of Polymer Capacitors

Vishay Releases DLA Tantalum Polymer Capacitors for Military and Aerospace

Vishay Expanded Inductor Portfolio With More Than 2000 Stock Items 

ST recently announced their new STSPIN820, which is an advanced microstepping motor driver that is capable of a stepping resolution of 1/256th of a step and integrates both the control logic and power stage in a small 24-pin QFN 4 × 4 mm package. Seems impressive.

 

Featured Figure 1. STSPIN820 microstepping motor driver. Image taken from the datasheet (PDF).

 

With a wide operating voltage range of 7 to 45 V, a host of protection features, and a low standby current of 45µA, this IC could be a good choice for applications such as 3D printers, sewing machines, and robotics.

 

A “Low” RDSon Value

This motor driver’s integrated power stage is advertised as having a low RDSon value (high side + low side) of 1Ω (typical). It seems to me, however, that 1Ω isn’t really all that low. In fact, in my dealings with motor drivers—granted my design experience in this regard is not exceedingly extensive—motor drivers with low RDSon values are in the range of hundreds of milliohms. So I would suggest that 1Ω might be better characterized as a typical RDSon value; if you disagree, let us know in the comments.

 

Figure 2. The STSPIN820’s “low”  RDSon values, from the datasheet (PDF).

 

External Sense Resistors

As noted in the datasheet, this IC requires two external sense resistors (RSNSA and RSNSB), and because these resistors play an important role in the PWM current control—for both slow decay and mixed decay current recirculation conditions—their values must be chosen carefully. Fortunately, ST has provided values for these resistors in a typical application (see image below), and they suggest values for other external passive components. They also offer a trick for easily achieving lower resistor values with higher power ratings; this trick—though it’s probably, hopefully, common knowledge for any electrical engineer—is simply placing multiple resistors in parallel. But hey, maybe ST thought that we might forget about this technique in this particular situation…so thanks, ST, for the reminder.

 

Figure 3. Recommended RSENSE resistor values and other recommended values for external components. Image taken from the datasheet (PDF).

 

Lately I’ve noticed datasheets that don’t offer much in the way of straightforward design guidance, so it’s good to see that ST has taken the time to provide this information.

 

A Set of Protection Features

The STSPIN820 comes with multiple protection features. Though not exactly uncommon among high-end (or even low-end) ICs these days, these features are nonetheless important additions to a reliable, user-friendly motor driver.

  • Short-circuit or overcurrent: Each power output node is protected against overload/overcurrent and short-circuit conditions, including short-to-ground, short-to-VS, and short-circuit between outputs. When an overcurrent condition occurs, the power stage is disabled and the Fault pin is driven low until the overcurrent condition is rectified (see image below).

 

Figure 4. Overcurrent and short-circuit protection management. Diagram taken from the datasheet (PDF).

 

  • Undervoltage lockout (UVLO): During power up, the power stage is disabled—and the Fault pin is forced low—until the voltage on the VS pin (actually, there are two VS pins and they must be at the same voltage) rises above the VS threshold voltage (VSth(ON)), which is 6.0 V (typical). The image below shows the undervoltage lockout protection scheme.

 

Figure 5. Undervoltage lockout (UVLO) protection management. Diagram taken from the datasheet (PDF).

 

  • Thermal shutdown: When the IC’s junction temperature reaches its threshold (TjSD = 160°C), the power stage is disabled and the Fault pin is driven low. Once the junction temperature retreats back to less than 120°C (which includes the thermal shutdown hysteresis value of 40°C), the fault condition is removed (see the image below).

 

Figure 6. Thermal shutdown protection management. Diagram taken from the datasheet (PDF).

 

The Microstepping Sequencer

For this device, ST uses three Mode inputs for achieving a stepping range from full-step to 1/256th of a step. As shown in the image below, each of the three mode settings (MODE1, MODE2, and MODE3) are clocked in on the rising edge of STCK (step clock input). And to allow for a very quick stepper motor response, the three mode settings can be changed at any time, and these changes are applied immediately.

 

Figure 7. Step mode configuration using the MODEx inputs, from the datasheet (PDF).

Related

Recent Posts

Advances in the Environmental Performance of Polymer Capacitors

8.10.2025
2

Researchers Demonstrated High Energy Ceramic Capacitors Stable in Wide Temperature Range

2.10.2025
24

Stackpole Offers High Voltage Plate Resistors up to 40KV

2.10.2025
18

How to Manage Supercapacitors Leakage Current and Self Discharge 

1.10.2025
39

Experimental Evaluation of Wear Failures in SMD Inductors

1.10.2025
36

Resonant Capacitors in High-Power Resonant Circuits

1.10.2025
37

Littelfuse Releases First Reflow-Compatible Illuminated Tactile Switch

1.10.2025
7

Vishay Unveils 5W Power Metal Strip Resistor in Compact 1206 Case Size

1.10.2025
24

Components Thermal and Frequency Challenges in 6G Base Stations

30.9.2025
18

Layer-by-Layer Fabrication of Thin Polypropylene-based Dielectrics

30.9.2025
24

Upcoming Events

Oct 14
16:00 - 17:00 CEST

Smart Sensors, Smarter AI: Building Reliable Edge Systems

Oct 17
12:00 - 14:00 EDT

External Visual Inspection per MIL-STD-883 TM 2009

Oct 20
October 20 - October 23

Digital WE Days 2025 – Virtual Conference

Oct 21
October 21 @ 12:00 - October 23 @ 14:15 EDT

Space and Military Standards for Hybrids and RF Microwave Modules

Oct 28
8:00 - 15:00 CET

Power Up Your Design: SN6507 and the Ready-to-Use Development Kit

View Calendar

Popular Posts

  • Buck Converter Design and Calculation

    0 shares
    Share 0 Tweet 0
  • Boost Converter Design and Calculation

    0 shares
    Share 0 Tweet 0
  • Flyback Converter Design and Calculation

    0 shares
    Share 0 Tweet 0
  • LLC Resonant Converter Design and Calculation

    0 shares
    Share 0 Tweet 0
  • SEPIC Converter Design and Calculation

    0 shares
    Share 0 Tweet 0
  • Dual Active Bridge (DAB) Topology Explained

    0 shares
    Share 0 Tweet 0
  • Ripple Current and its Effects on the Performance of Capacitors

    3 shares
    Share 3 Tweet 0
  • What is a Dielectric Constant and DF of Plastic Materials?

    4 shares
    Share 4 Tweet 0
  • Flying Capacitors Explained

    0 shares
    Share 0 Tweet 0
  • MLCC and Ceramic Capacitors

    0 shares
    Share 0 Tweet 0

Newsletter Subscription

 

Passive Components Blog

© EPCI - Leading Passive Components Educational and Information Site

  • Home
  • Privacy Policy
  • EPCI Membership & Advertisement
  • About

No Result
View All Result
  • Home
  • Knowledge Blog
  • Premium Suppliers

© EPCI - Leading Passive Components Educational and Information Site

This website uses cookies. By continuing to use this website you are giving consent to cookies being used. Visit our Privacy and Cookie Policy.
Go to mobile version