L6235Q Datasheet, PDF (1/33 Pages) STMicroelectronics – Tacho output for speed loop

L6235Q
DMOS driver for 3-phase brushless dc motor
Features
■ Operating supply voltage from 8 to 52 V
■ 5.6 A output peak current
■ R_DS(on) 0.3 Ω typ. value @ T_J = 25 °C
■ Operating frequency up to 100 kHz
■ Non-dissipative overcurrent protection
■ Diagnostic output
■ Constant t_OFF PWM current controller
■ Slow decay synchronous rectification
■ 60° and 120° Hall effect decoding logic
■ Brake function
■ Tacho output for speed loop
■ Cross conduction protection
■ Thermal shutdown
■ Undervoltage lockout
■ Integrated fast freewheeling diodes
Figure 1. Block diagram
QFN-48
(7 x 7 mm)
Description
The L6235Q is a DMOS fully integrated 3-phase
motor driver with overcurrent protection. Realized
in BCDmultipower technology, the device
combines isolated DMOS power transistors with
CMOS and bipolar circuits on the same chip. The
device includes all the circuitry needed to drive a
3-phase BLDC motor including: a 3-phase DMOS
bridge, a constant OFF time PWM current
controller and the decoding logic for single ended
Hall sensors that generates the required
sequence for the power stage. Available in
QFN48 7x7 package, the L6235Q features a non-
dissipative overcurrent protection on the high-side
power MOSFETs and thermal shutdown.
VBOOT
VCP
DIAG
EN
BRAKE
FWD/REV
H3
H2
H1
RCPULSE
TACHO
VBOOT
CHARGE
PUMP
THERMAL
PROTECTION
OCD
OCD1
OCD2
OCD3
OCD
VBOOT
OCD1
10V
VBOOT
HALL-EFFECT
SENSORS
DECODING
LOGIC
GATE
LOGIC
OCD2
10V
VBOOT
TACHO
MONOSTABLE
10V 5V
VOLTAGE
REGULATOR
OCD3
10V
ONE SHOT
MONOSTABLE
PWM
MASKING
TIME
+
SENSE
-
COMPARATOR
VS_A
OUT1
OUT2
SENSEA
VSB
OUT3
SENSEB
VREF
RCOFF
AM02555v1
November 2011
Doc ID 018997 Rev 2
1/33
www.st.com
33