bd6709fs ROHM Co. Ltd., bd6709fs Datasheet - Page 13

• Manufacturer Part Number: bd6709fs
• Description: Dc Brushless Motor Drivers For Cooling Fans Speed Controllable Single-phase Full-wave Dc Brushless Fan Motor Drivers
• Manufacturer: ROHM Co. Ltd.

●Block diagram, application circuit, and pin assignment(Constant etc are for reference)
Adjust the gain according to
the characteristics of level
amplifier gain setting resistor.
Bias resistor for thermistor.
Speed control is enabled by
thermistor.
Set
speed and full torque time in
restarting.
Output
resistor.
wattage because large current
flows.
P.21,22
P.24
P.22
P.22
PIN No.
the
REG：Internal reference voltage OSC：Oscillation circuit REF：Reference voltage generating circuit
TSD：Thermal shutdown(heat rejection circuit)
◎BD6709FS
1
2
3
4
5
6
7
8
1) DC input application
current
Pay
The example of an application for rotation speed control by thermistor.
minimum
Terminal
attention
LAOUT
COSC
OUT1
name
VMIN
GND
LAIN
RNF
VTH
detecting
rotating
to
GND terminal
Oscillating capacitor connecting terminal
Level amplifier output terminal
(for setting speed control gain)
Level amplifier input terminal
(for setting speed control gain)
Variable speed input terminal
(thermistor connecting terminal)
Minimum rotating speed setting terminal
Motor output terminal 1
Output current detecting resistor connecting terminal
(motor GND terminal)
330pF
～1000pF
5kΩ
～200kΩ
5kΩ
～200kΩ
5kΩ
～200kΩ
～10μF
～5Ω
LAOUT
Function
COSC
OUT1
VMIN
GND
LAIN
RNF
VTH
1
2
3
4
5
6
7
8
OSC
REG
-
+
Auto Restart
-
+
Lock Detect
TSD
Pre Driver
Control
M
13/40
PIN No.
15
10
11
12
13
14
16
9
REF
Terminal
+
-
+
-
VREF
OUT2
name
Vcc
CS
CL
H+
FG
H-
FG
VREF
H-
H+
CL
Vcc
CS
OUT2
16
15
14
13
10
12
11
10
9
Motor output terminal 2
Output current detecting terminal
Power supply terminal
Current limiting input terminal
Hall input terminal +
Hall input terminal -
Reference voltage terminal
Rotating speed pulse signal output terminal
HALL
Vcc
5kΩ
～200kΩ
100Ω
～200kΩ
100pF
～0.1μF
1kΩ
～200kΩ
Function
Set according to the amplitude
of hall element output and hall
input voltage range.
Current limit setting resistor.
Use a larger resistor in order to
reduce
from VREF.
Take a measure against Vcc
voltage rise due to reverse
connection of power supply.
RNF
low-pass filter.
This is an open collector
output. Connect a pull-up
resistor.
P.37
P.28
P.24
P.36
P.24
voltage
power
consumption
smoothing