SLRS064B June   2014  – August 2016 ULN2003B

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
  6. 6 Specifications
    1. 6.1 Absolute Maximum Ratings
    2. 6.2 ESD Ratings
    3. 6.3 Recommended Operating Conditions
    4. 6.4 Thermal Information
    5. 6.5 Electrical Characteristics, TA = 25°C
    6. 6.6 Electrical Characteristics, TA = -40°C to +105°C
    7. 6.7 Switching Characteristics, TA = 25°C
    8. 6.8 Switching Characteristics, TA = -40°C to +105°C
    9. 6.9 Typical Characteristics
  7. 7 Parameter Measurement Information
  8. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
    4. 8.4 Device Functional Modes
      1. 8.4.1 Inductive Load Drive
      2. 8.4.2 Resistive Load Drive
  9. 9 Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Application
      1. 9.2.1 Design Requirements
      2. 9.2.2 Detailed Design Procedure
        1. 9.2.2.1 Drive Current
        2. 9.2.2.2 Output Low Voltage
        3. 9.2.2.3 Power Dissipation and Temperature
      3. 9.2.3 Application Curves
  10. 10Power Supply Recommendations
  11. 11Layout
    1. 11.1 Layout Guidelines
    2. 11.2 Layout Example
  12. 12Device and Documentation Support
    1. 12.1 Receiving Notification of Documentation Updates
    2. 12.2 Community Resources
    3. 12.3 Trademarks
    4. 12.4 Electrostatic Discharge Caution
    5. 12.5 Glossary
  13. 13Mechanical, Packaging, and Orderable Information

Package Options

Mechanical Data (Package|Pins)
Thermal pad, mechanical data (Package|Pins)
Orderable Information

9 Application and Implementation

NOTE

Information in the following applications sections is not part of the TI component specification, and TI does not warrant its accuracy or completeness. TI’s customers are responsible for determining suitability of components for their purposes. Customers should validate and test their design implementation to confirm system functionality.

9.1 Application Information

ULN2003B will typically be used to drive a high voltage and/or current peripheral from an MCU or logic device that cannot tolerate these conditions. The following design is a common application of ULN2003B, driving inductive loads. This includes motors, solenoids and relays. Figure 23 is a typical block diagram representation of this application.

9.2 Typical Application

ULN2003B relay_drv.gif Figure 23. ULN2003B as Inductive Load Driver

9.2.1 Design Requirements

For this design example, use the parameters listed in Table 1 as the input parameters.

Table 1. Design Parameters

DESIGN PARAMETER (1) EXAMPLE VALUE
GPIO Voltage 3.3 V or 5 V
Coil Supply Voltage 12 V to 48 V
Number of Channels 7
Output Current (RCOIL) 20 mA to 300 mA per channel (See Figure 5)
Duty Cycle See Figure 6 to Figure 14
(1) These test conditions can not be run simultaneously.

9.2.2 Detailed Design Procedure

When using ULN2003B in a coil driving application, determine the following:

  • Input Voltage Range
  • Temperature Range
  • Output and Drive Current
  • Power Dissipation

9.2.2.1 Drive Current

The coil current is determined by the coil voltage (VSUP), coil resistance and output low voltage (VOL or VCE(SAT)).

Equation 1. ICOIL = (VSUP – VCE(SAT)) / RCOIL

9.2.2.2 Output Low Voltage

The output low voltage (VOL) is the same thing as VCE(SAT) and can be determined by, Figure 1, Figure 2, or Figure 4.

9.2.2.3 Power Dissipation and Temperature

The number of coils driven is dependent on the coil current and on-chip power dissipation. The number of coils driven can be determined by Figure 6 or Figure 7.

For a more accurate determination of number of coils possible, use Equation 2 to calculate ULN2003B on-chip power dissipation PD:

Equation 2. ULN2003B eq1_lrs059.gif

where

  • N is the number of channels active together.
  • VOLi is the OUTi pin voltage for the load current ILi. This is the same as VCE(SAT)

In order to guarantee reliability of ULN2003B and the system the on-chip power dissipation must be lower that or equal to the maximum allowable power dissipation (PD(MAX)) dictated by Equation 3.

Equation 3. ULN2003B eq2_lrs059.gif

where

  • TJ(MAX) is the target maximum junction temperature.
  • TA is the operating ambient temperature.
  • θJA is the package junction to ambient thermal resistance.

TI recommends to limit ULN2003B IC’s die junction temperature to less than 125°C. The IC junction temperature is directly proportional to the on-chip power dissipation.

9.2.3 Application Curves

The following curves were generated with ULN2003B driving an OMRON G5NB relay – Vin = 5.0V; Vsup= 12 V and RCOIL= 2.8 kΩ

ULN2003B D010_ULN2003B.gif Figure 24. Output Response With Activation
of Coil (Turn On)
ULN2003B D009_ULN2003B.gif Figure 25. Output Response With De-activation
of Coil (Turn Off)