INT202
INT202 Functional Description
5 V Regulator
HSD1/HSD2
Pulse Circuit
The 5 V linear regulator circuit provides
the supply voltage for the control logic
andhigh-voltagelevelshiftcircuit. This
allows the logic section to be directly
compatible with 5 V CMOS logic
without the need of an external 5 V
supply.
The HSD1 and HSD2 outputs are
connected to integrated high-voltage N-
channel MOSFET transistors which
perform the level-shifting function for
communication to the high-side driver.
Controlled current capability allows the
drain voltage to float with the high-side
driver. Twoindividualchannelsproduce
a true differential communication
channel for accurately controlling the
high-side driver in the presence of fast
moving high-voltage waveforms.
The pulse circuit provides the two high-
voltagelevelshifterswithprecisetiming
signals. Two pulses are sent over HSD1
to signal the high-side driver to turn on.
One pulse is sent over HSD2 to signal
the high-side driver to turn off. The
combination
of
differential
communication with the precise timing
provides maximum immunity to noise.
Undervoltage Lockout
Theundervoltagelockoutcircuitdisables
the LS OUT pin and both HSD pins
whenever the VDD power supply falls
below typically 9.0 V, and maintains
thisconditionuntiltheVDD powersupply
rises above typically 9.35 V. This
guarantees that both MOSFETs will
remain off during power-up or fault
conditions.
Driver
The CMOS drive circuit provides drive
power to the gate of the MOSFET used
onthelow sideofthehalfbridgecircuit.
The driver consists of a CMOS buffer
capable of driving an external transistor
gate at up to 15 V.
HV+
8
7
6
5
D3
R2
PHASE 2
C2
INT201
Q2
D1
1
8
2
3
4
5
3-PHASE
SRM
V
DD
7
6
PHASE 1
PHASE 3
C1
INT202
CONTROL
HV-
Q1
1
2
3
4
R1
D2
PI-1473-042695
Figure 4. Using the INT202 and INT201 to Drive a Switched Reluctance Motor.
F
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POWERINT [ Power Integrations ]
