DRV401_15 Datasheet, PDF (20/36 Pages) Texas Instruments – Sensor Signal Conditioning IC for Closed-Loop Magnetic Current Sensor

DRV401
SBVS070B − JUNE 2006 − REVISED MAY 2009
www.ti.com
V_DD1
1
4
2
106ms
V(ERROR)
V(I_COMP2)
R_SH = 10Ω
V_OUT
3
20ms/div
a) Demagnetization cycle on power-up. With power-up, the V_OUT across the compensation coil centers around half the supply and then
starts the cycle after the 4V threshold is exceeded. The ERROR flag resets to H after the cycle is completed.
V_DD1
42µs
1
1
V(ERROR)
4
4
V(IS1)
2
2
3
V(I_COMP2)
Initial setting upon
closing of feedback loop.
3
20ms/div
b) Power-up without demagnetization. The probe oscillation V(IS1)
starts just before ERROR resets—15µs after the supply voltage cross-
es the 4V threshold.
V(DEMAG)
106ms
V(ERROR)
V(I_COMP2)
R_SH = 10Ω
V_OUT
20ms/div
c) Demagnetization cycle on command.
V(DEMAG)
1
V(ERROR)
4
V(I_COMP2)
2
3.4ms
V_OUT
3
500µs/div
R_SH = 10Ω
d) Abort of demagnetization cycle. The ERROR flag resets to H (as shown) and the output settles back to normal opera-
tion.
Figure 7. Demagnetization and Power-On Timing
20