TLE82453-3SA_15 Datasheet, PDF (22/71 Pages) Infineon Technologies AG – 3 Channel High-Side and Low-Side Linear Solenoid Driver IC

7
Power Stages
TLE82453-3SA
Power Stages
7.1
Overview
There are three output channels implemented in this device. The output power stages of each channel consists
of a half bridge made up of two n-channel DMOS transistors and a current sensing resistor. An internal charge
pump generates the voltage required to switch the n-channel DMOS high-side switches. The switches are
protected from external failures by built in overcurrent and overtemperature detection circuits.
The half bridge arrangement allows the use of active freewheeling, which reduces the power dissipation of the
device.The arrangement also allows each channel to be individually programmed for lowside or highside drive.
The output current slew rate of the power stages can be programmed to one of three values by programming the
CONFIGURATION register by SPI.
Charge Pump
VIO
CSB
SCK
control
logic
SO
SI
+ 5V
LSUPx
LOADx
PGNDx
Figure 6 Power Stages
Power Stage.vsd
7.2
Channel Disabled
When the channel is disabled, both transistors of the half bridge are turned off. The output stage is in a high output
impedance state in this condition. The channel is disabled if the EN pin is 0, or the EN bit is 0, or the set point = 0.
7.3
Channel Enabled
When a channel is configured for lowside operation, the lowside DMOS switch is the “drive” switch and the
highside DMOS switch is the “recirculation” switch. Likewise, when a channel is configured for highside operation,
the highside DMOS switch is the “drive” switch and the lowside switch is the “recirculation” switch. In normal
operation, the “drive” switch is turned on and off with the duty cycle needed to regulate the solenoid current at the
target value. During the time that the “drive” switch is turned off, the device is in active freewheeling mode. The
“recirculation” switch is turned on in this mode to reduce the voltage drop across the device during recirculation.
Data Sheet
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22
Rev 1.0, 2015-03-27