NJM3777 데이터 시트보기 (PDF) - Japan Radio Corporation
부품명
상세내역
제조사
NJM3777 Datasheet PDF : 10 Pages
| |||
NJM3777
s APPLICATIONS INFORMATION
Current control
The regulated output current level to the motor winding is determined by the voltage at the reference input and the
value of the sensing resistor, RS. The peak current through the sensing resistor (and the motor winding) can be
expressed as:
IM,peak = 0.1•VR / RS [A]
With a recommended value of 0.5 ohm for the sensing resistor RS, a 2.5 V reference voltage will produce an output
current of approximately 500 mA. RS should be selected for maximum motor current. Be sure not to exceed the
absolute maximum output current which is 900 mA. Chopping frequency, winding inductance and supply voltage
also affect the current, but to much less extent.
For accurate current regulation, the sensing resistor should be a 0.5 - 1.0 W precision resistor, i. e. less than 1%
tolerance and low temperature coefficient.
+5 V
V MM
0.1 µF
0.1 µF
+
10 µF
13
5
20
V
10 Phase1 CC
V
MM1
V
MM2
M A1
4
11 Dis1
8 VR1
15 Phase 2
NJM3777E3
MB1 2
21
M A2
14 Dis2
17 V R2
MB2 23
RC GND C1
E1 C2
E2
12 6, 7, 9
3 16
22
+5 V 12 kΩ
18, 19
STEPPER
MOTOR
4 700 pF
GND (VCC )
RS
0.47 Ω
RS
0.47 Ω
Pin numbers refer
to EMP package.
GND (VMM )
Figure 6. Typical stepper motor driver application with NJM3777
VCC (+5 V)
0.1 F
0.1 F
V MM
+
10 F
To
P
+2.5V
13
D0
4
VDD
6 D7
14 A0 NJU39612E2
5
16
20
WR
CS
RESET
1
V Ref
VSS
17
GND
(VCC )
13
5
20
Sign1 3
V
10 Phase1 CC
V
MM1
V
MM2
MA1
4
DA1 2
Sign2 18
DA2 19
11 Dis1
8 VR1
NJM3777E3
15 Phase 2
14 Dis2
17 V R2
RC GND C1
E1 C2
MB1 2
21
MA2
MB2 23
E2
12 6, 7, 9
3 16
22
+5 V 12 k‰
18, 19
4700 pF
0.47 ‰ R S 0.47 ‰ R S
STEPPER
MOTOR
Pin numbers refer
to EMP package.
GND (VMM)
Figure 7. Typical microstepping application with NJU39612
Share Link: 