UC1625
UC2625
UC3625
SLUS353A - NOVEMBER 1999
Brushless DC Motor Controller
FEATURES
• Drives Power MOSFETs or Power Darlingtons
Directly
• 50V Open Collector High-Side Drivers
• Latched Soft Start
• High-speed Current-Sense Amplifier with Ideal
Diode
• Pulse-by-Pulse and Average Current Sensing
• Over-Voltage and Under-Voltage Protection
• Direction Latch for Safe Direction Reversal
• Tachometer
• Trimmed Reference Sources 30mA
• Programmable Cross-Conduction Protection
• Two-Quadrant and Four-Quadrant Operation
DESCRIPTION
The UC3625 family of motor controller ICs integrate most of the
functions required for high-performance brushless DC motor con-
trol into one package. When coupled with external power
MOSFETs or Darlingtons, these ICs perform fixed-frequency PWM
motor control in either voltage or current mode while implementing
closed loop speed control and braking with smart noise rejection,
safe direction reversal, and cross–conduction protection.
Although specified for operation from power supplies between 10V
and 18V, the UC1625 can control higher voltage power devices
with external level-shifting components. The UC1625 contains fast,
high-current push-pull drivers for low-side power devices and 50V
open-collector outputs for high-side power devices or level shifting
circuitry.
The UC1625 is characterized for operation over the military tem-
perature range of –55°C to +125°C, while the UC2625 is charac-
terized from –40°C to +105°C and the UC3625 is characterized
from 0°C to 70°C. (NOTE: ESD Protection to 2kV)
application
INFO
available
UDG-99045
21
27
25
22
6
28
1
15
24326
10kΩ
3kΩ
10kΩ
2 19
20
16
11
20µF
100nF
20µF
100nF
+
R
OSC
33kΩ
2200pF
C
OSC
68kΩ
R
T
3nF
C
T
BRAKE
5nF 100nF
23 8 9 10 4 5 7
2nF
2nF
2nF
100nF
10kΩ
5nF
240Ω
240Ω
17
18
14
13
12
3kΩ
2N3906
100nF
1k
4kΩ
TO OTHER
CHANNELS
TO OTHER
CHANNELS
10Ω
2N3904
10Ω
IRF9350
IRF532
3kΩ
FROM
HALL
SENSORS
VMOTOR+15V
+5V TO HALL
SENSORS
VREF
0.02Ω
R
S
TO
MOTOR
0.02Ω
R
D
REQUIRED
FOR
AVERAGE
CURRENT
SENSING
REQUIRED
FOR BRAKE
AND FAST
REVERSE
100µF
+
UC3625
DIR
QUAD
TYPICAL APPLICATION