FAN8423D3 Fairchild Semiconductor, FAN8423D3 Datasheet - Page 10

• Manufacturer Part Number: FAN8423D3
• Description: Motor / Motion / Ignition Controllers & Drivers BLDC Motor Driver 3Phase 5V Interface
• Manufacturer: Fairchild Semiconductor
• Type: 3 Phase BLDC Motor Driverr

Specifications of FAN8423D3

• Operating Supply Voltage: 15 V
• Supply Current: 1.3 A
• Mounting Style: SMD/SMT
• Package / Case: SSOP-28
• Operating Temperature: - 20 C to + 75 C
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

FAN8423D3
4. Tsd (Thermal Shutdown)
When the chip temperature rises up to about 175 C, the Q2 turns on so that the output driver shuts down. When the chip tem-
perature falls off to about 150 C, then the Q2 turns off so that the driver is to operate normally. TSD has the temperature hys-
teresis of about 25 C.
5. Rotational Direction Detection
1) The forward and the reverse rotations of the CD are detected by using the D-F/F and the truth table as shown above.
2) The rotational direction of the CD can be explained by the output waveform of the Hall sensors. Let the three outputs of
On the other hand, if the spindle rotates in forward rotation, the phase relationship is H3 H2 H1 as shown in Fig.(b)
10
Hall sensors be H1, H2 and H3 respectively.
When the spindle rotates in reverse direction, the Hall sensor output waveform are shown in Fig.(a). Thus the phases are in
order H1 H2 H3 with a 120 phase difference.
H2+
H3+
H2-
H3-
+
-
+
-
H1
H2
H3
D
CK
D-F/F
Q
BIAS
Vcc
DIR
20
Oct. 2000.
Rev. 1.0.1
Q2
Controller
Gain
Rotation
Forward
Reverse
(a) Reverse rotation
20
High
Low
DIR