Other Parts Discussed in Thread: DRV110
I implemented the DRV120 drivers on my board for driving solenoid valves. I noticed that there is variation of Tpeak & Ipeak values when I view the current waveforms. Also the Tpeak values are consistently les than the intended value. The datasheet only gives Typical values for certain Test Conditions (external component settings). I'd like to verify if there are any issues w/ my implementation or if the drivers should have this observed tolerance. Here are the external component values I'm using:
Ckeep = 2.2uF (set for 165mS)
Rpeak = 205KΩ (set for 81.3mA)
Rhold = 110KΩ (set for 60.6mA)
Rpeak = 196KΩ (set for 20.4KHz)
I use 7 DRV120 drivers on each board. Here are the parameters I measured on 2 boards:
| Bd # 5 | |||
| Driver # | Tpeak(mS) | Ipeak(mA) | Ihold(mA) |
| 1 | 149 | 73.6 | 56.8 |
| 2 | 124 | 77.6 | 60.0 |
| 3 | 146 | 76.0 | 60.0 |
| 4 | 119 | 78.4 | 60.8 |
| 5 | 139 | 76.0 | 60.8 |
| 6 | 128 | 75.2 | 59.2 |
| 7 | 146 | 76.8 | 60.8 |
| Bd # 6 | |||
| Driver # | Tpeak(mS) | Ipeak(mA) | Ihold(mA) |
| 1 | 138 | 79.2 | 61.6 |
| 2 | 130 | 75.2 | 59.2 |
| 3 | 128 | 75.2 | 58.2 |
| 4 | 149 | 76.0 | 59.2 |
| 5 | 130 | 74.4 | 59.2 |
| 6 | 140 | 76.0 | 60.0 |
| 7 | 132 | 76.8 | 60.8 |
Note that I use the same solenoid as the load for each driver's measurement. The solenoid DCR = 265Ω, L = 0.69H.
Thx for any info.
