米6体育平台手机版

SLVA504A February 2012 – July 2021 DRV8243-Q1 , DRV8244-Q1 , DRV8245-Q1 , DRV8800 , DRV8801 , DRV8802 , DRV8803 , DRV8804 , DRV8805 , DRV8806 , DRV8811 , DRV8812 , DRV8813 , DRV8814 , DRV8818 , DRV8821 , DRV8823 , DRV8824 , DRV8825 , DRV8828 , DRV8829 , DRV8830 , DRV8832 , DRV8832-Q1 , DRV8833 , DRV8834 , DRV8835 , DRV8836 , DRV8837 , DRV8840 , DRV8841 , DRV8842 , DRV8843 , DRV8844 , DRV8870 , DRV8871 , DRV8872

1Sources of Power Dissipation in an Integrated Driver
1. 1.1 H-Bridge
  1. 1.1.1 H-Bridge Driver Using High-Side Recirculation
  2. 1.1.2 H-Bridge Driver Using Low-Side Recirculation
2. 1.2 Half Bridge
  1. 1.2.1 Half Bridge Driver Using High-Side Recirculation
  2. 1.2.2 Half Bridge Driver Using Low-Side Recirculation
2Example Calculation
1. 2.1 H-Bridge
  1. 2.1.1 High-Side Recirculation Example
  2. 2.1.2 Low-Side Recirculation Example
2. 2.2 Half Bridge
  1. 2.2.1 Half-Bridge High-Side Recirculation Example
  2. 2.2.2 Half-Bridge Low-Side Recirculation Example
3References
4Revision History

2.1.1 High-Side Recirculation Example

Table 2-1 Power Dissipation for H-Bridge with High-side Recirculation

Region	Time ratio within PWM cycle	HS1 [W]	HS2 [W]	LS2 [W]
1	50% = On-time × 20 KHz₁	100 mΩ × 1A²	0	100 mΩ × 1A²
2	13.5 V/(13.5 V/μs) x 20 KHz	100 mΩ × 1A²	0	0.5 x 13.5 V x 1 A
3	100 ns x 10 KHz	100 mΩ × 1A²	1 V x 1 A	0
4	1 V/(13.5 V/μs) x 20 KHz	100 mΩ × 1A²	0.5 x 1 V x 1 A	0
5	(1 - 50%) = Off-time × 20 KHz₁	100 mΩ × 1A²	100 mΩ × 1A²	0
6	1 V/(13.5 V/μs) x 20 KHz	100 mΩ × 1A²	0.5 x 1 V x 1 A	0
7	100 ns x 20 KHz	100 mΩ × 1A²	1 V x 1 A	0
8	13.5 V/(13.5 V/μs) x 20 KHz	100 mΩ × 1A²	0	0.5 x 13.5 V x 1 A

P_HS1 = 100 mΩ × 1 A² = 0.1 W

P_LS1 = 0

P_HS2 = [100 mΩ × 1 A² x (1-0.5)] + [2 x 1 V x 1 A x 100 ns x 20 KHz] = 0.054 W

P_LS2 = [ 100 mΩ × 1 A²x 0.5] + [13.5 x 1 A x 13.5 V/ (13.5 V/μs) x 20 KHz] = 0.32 W

It is not necessary to include P_IVM and P_LDO as their impact is usually minimal enough to be inconsequential. That being said, they can be calculated as:

P_IVM = 13.5 V × 10 mA = 0.135 W and P_LDO = 5 mA × (13.5 V - 5 V) = 0.0425 W

P_TOT = P_HS1 + P_LS1 + P_HS2 + P_LS2 = 0.1 + 0 + 0.054 + 0.32 = 0.474 W

or P_TOT = 0.474 W + P_IVM + P_LDO = 0.6515 W