SLVA505A February   2012  – July 2024 DRV8800 , DRV8801 , DRV8802 , DRV8803 , DRV8804 , DRV8805 , DRV8806 , DRV8811 , DRV8812 , DRV8813 , DRV8814 , DRV8818 , DRV8821 , DRV8823 , DRV8824 , DRV8828 , DRV8829 , DRV8830 , DRV8832 , DRV8832-Q1 , DRV8833 , DRV8834 , DRV8835 , DRV8836 , DRV8837 , DRV8840 , DRV8841 , DRV8842 , DRV8843 , DRV8844 , DRV8870 , DRV8871 , DRV8872

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1Factors Limiting the Maximum Output Current of a Motor Driver
    1. 1.1 Thermal Limitations
    2. 1.2 Overcurrent Protection (OCP) Limitations
    3. 1.3 Silicon and Package Limitations
    4. 1.4 PCB Limitations and Thermal Management Techniques
      1. 1.4.1 Exposed Pad Packages
      2. 1.4.2 Continuous Copper Planes
      3. 1.4.3 Copper Thickness
      4. 1.4.4 Thermal Vias
      5. 1.4.5 Summary of Thermal Management Techniques
    5. 1.5 Thermal Estimations
  5. 2TI Motor Driver OCP Operation
  6. 3TI Motor Driver Data Sheet Ratings
    1. 3.1 Description
    2. 3.2 Absolute Maximum Ratings
    3. 3.3 Recommended Operating Conditions
    4. 3.4 Thermal Information
    5. 3.5 Electrical Characteristics
  7. 4References
  8. 5Revision History

3.5 Electrical Characteristics

The electrical characteristics tables include specifications showing the maximum current delivered from the motor driver. The first is RDS(ON):

Table 3-4 Electrical Characteristics H-BRIDGE FETS
MINTYPMAXUNIT
H-BRIDGE FETS
RDS(ON)HS FET ON-resistanceVM = 5 V, IO = 500 mA, TJ = 25°C200mΩ
VM = 5 V, IO = 500 mA, TJ = 85°C325
VM = 2.7 V, IO = 500 mA, TJ = 25°C250
VM = 2.7 V, IO = 500 mA, TJ = 85°C350
LS FET ON-resistanceVM = 5 V, IO = 500 mA, TJ = 25°C160mΩ
VM = 5 V, IO = 500 mA, TJ = 85°C275
VM = 2.7 V, IO = 500 mA, TJ = 25°C200
VM = 2.7 V, IO = 500 mA, TJ = 85°C300

In this case, the RDS(ON) is specified separately for high-side and low-side FETs, at several power-supply voltages and temperatures. This data is used to estimate the power dissipation inside the device, applying Ohm's law as described in Section 1.1.

The electrical characteristics tables also include information on the OCP and overtemperature shutdown circuits:

Table 3-5 Electrical Characteristics Protection Circuits
MINTYPMAXUNIT
PROTECTION CIRCUITS
IOCPOCP trip level23.3A
tDEGOCP deglitch time2.25µs
tOCPOCP period1.35ms
tTSDThermal shutdown temperatureDie temperature150160180°C

The OCP trip level (IOCP), the maximum amount of current that the device can drive without activating the OCP circuit, is illustrated here. The OCP deglitch time is also listed. If the resulting output current remains above IOCP for at least tDEG, then OCP is activated.

This device does automatic re-try in the event of OCP, the device can re-enable the outputs after some period of time. This time is listed here as tOCP, the OCP period.

The overtemperature shutdown temperature (referred to as thermal hysteresis in some data sheets) is also listed in this table. The device shuts down if the temperature, as measured on the die, is exceeded. Typically, the device automatically re-enables the device when the temperature falls to a safe level, 10-40°C below the threshold.