AN44066A Datasheet, PDF (26/29 Pages) Panasonic Semiconductor – Driver IC for Stepping Motor

AN44066A
„ Usage Notes (continued)
12. PWMSW, PHA1, PHB1 pins
Under conditions where VM power supply is shutdown in standby mode (STBY pin = High level), when applying approx. 0.7 V
(TYP) or more to PWMSW (Pin 24), PHA1 (Pin 25), PHB1 (Pin 26), the current flows into above-mentioned pins owing to
parasitic elements in the LSI and the current flowing into the above-mentioned pins varies from the current determined by pull
down resistance. In addition, the current flowing into PHA1/PHA2 is 341.4 μA (impedance = approx. 9.1 kΩ) at 3.3 V, while that
into PWMSW is 323.2 μA (impedance = approx. 9.7 kΩ) at 3.3 V. There is no problem that the voltage up to rating is applied to
the above-mentioned pins. However, it is recommended to set the voltage applied to the above-mentioned to 0.7 V or less at
shutdown of VM power supply in standby mode.
Also, in case of the voltage of above-mentioned pins > S5VOUT(Pin 21) – 0.2 V at power on to VM power supply, the current
flows owing to parasitic elements in the LSI, and the current flowing into the above-mentioned pins varies (refer to Fig. 2, 3).
As the same as at standby, there is no problem that the voltage up to rating is applied to the above-mentioned pins. However, it is
recommended to set the voltage applied to the above-mentioned pins to 4.3 V or less.
400
300
200
100
0
0
S5VOUT = 4.5 V
S5VOUT = 5.0 V
S5VOUT = 5.5 V
Z = 200 kΩ
ZZ=≅約44.7.7kkΩΩ
1
2
3
4
5
6
_____
PHA1/PHB1=4.3V
PHA1/PHB1 voltage [V]
Fig. 2 Input impedance of PHA1/PHB1 at VM power supply power on
400
350
S5VOUT = 4.5 V
300
250
S5VOUT = 5.0 V
200
150
S5VOUT = 5.5 V
100
Z = 200 kΩ
50
0
ZZ=≅約4.47.7kkΩΩ
0
1
2
3
4
5
6
PWM^PWS^MW^SWv^電ol^圧tag^[Ve ^][V] ^PWMSW=4.3V
Fig. 3 Input impedance of PWMSW at VM power supply power on
SDL00014AEB
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