SLIS032B July   1995  – June 2015 TPIC6B595

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
    6. 6.6 Switching Characteristics
    7. 6.7 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
      1. 8.3.1 Serial-In Interface
      2. 8.3.2 Clear Register
      3. 8.3.3 Output Control
      4. 8.3.4 Cascaded Application
      5. 8.3.5 Current Limit Function
    4. 8.4 Device Functional Modes
      1. 8.4.1 Operation With V(VCC) < 4.5 (Minimum V(VCC))
      2. 8.4.2 Operating With 5.5 V < V(VCC) < 6 V
  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
      3. 9.2.3 Application Curve
  10. 10Power Supply Recommendations
  11. 11Layout
    1. 11.1 Layout Guidelines
    2. 11.2 Layout Example
  12. 12Device and Documentation Support
    1. 12.1 Community Resources
    2. 12.2 Trademarks
    3. 12.3 Electrostatic Discharge Caution
    4. 12.4 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

The TPIC6B595 device is a serial-in parallel-out, Power+LogicE 8-bit shift register with low-side switch DMOS outputs rating of a 150 mA per channel. The device is designed for use in systems that require relatively high load power. The device contains a built-in voltage clamp on the outputs for inductive transient protection. Power driver applications include relays, solenoids, and other medium currentor high-voltage loads. The following focuses on automotive cluster applications for the TPIC6B595 device.

9.2 Typical Application

The typical application of the TPIC6B595 device is the automotive cluster driver. In this example, two TPIC6B595 power shift registers are cascaded and used to turn on LEDs in the cluster panel. In this case, the LED must be updated after all 16 bits of data have been loaded into the serial shift registers. MCU outputs the data to the serial input (SER IN) while clocking the shift register clock (SRCK). After the 16th clock, a pulse to the register clock (RCK) transfers the data to the storage registers. If output enable (G) is low, then the LEDs are turned ON corresponding to the status word with ones being ON and zeros OFF. With this simple scheme, MCU use SPI interface can turn on 16 LEDs using only two ICs as illustrated in Figure 14.

TPIC6B595 typ_app_slis032.gifFigure 14. Typical Application Schematic

9.2.1 Design Requirements

Use the design parameters in Table 1 for this design example.

Table 1. Design Parameters

DESIGN PARAMETER EXAMPLE VALUE
VSUPPLY 9-16 V
V(D1), V(D2), V(D3), V(D4), V(D5), V(D6),V(D7), V(D8) 2 V
V(D9), V(D10),V(D11), V(D12), V(D13), V(D14),V(D15), V(D16) 3.3 V
I(D1), I(D2), I(D3), I(D4), I(D5), I(D6),I(D7), I(D8) 20mA When Vbattery is 12 V
I(D9), I(D10), I(D11), I(D12), I(D13), I(D14),I(D15), I(D16) 30mA When Vbattery is 12 V

9.2.2 Detailed Design Procedure

To begin the design process, one must decide on a few parameters. The designer must know the following:

  • Vsupply - LED supply is connect battery directly or fix voltage, this application connect the battery directly.
  • V(Dx) – LED forward voltage
  • I(Dx) – LED setting current when battery is 12 V.

Equation 1. TPIC6B595 Equation_1.gif

When Vsupply is 9 V,

Equation 2. TPIC6B595 Equation_2.gif

When Vsupply is 16 V,

Equation 3. TPIC6B595 Equation_3.gif
Equation 4. TPIC6B595 Equation_5.gif

When Vsupply is 9 V,

Equation 5. TPIC6B595 Equation_6.gif

When Vsupply is 16 V,

Equation 6. TPIC6B595 Equation_7.gif

NOTE

If customers can accept the current variation when battery voltage is changing, they can connect to the battery directly. If customers need the less variation of current, they must use the voltage regulator as supply voltage of LED, or change to constant current LED driver directly.

9.2.3 Application Curve

TPIC6B595 app_curve_slis032.pngFigure 15. CH1 is SRCK, CH2 is RCK, CH3 is SER IN, CH4 is D1 current