MPQ8039 – HIGH CURRENT POWER HALF BRIGDE, AEC-Q100 QUALIFIED
MPQ8039 Rev.1.02 www.MonolithicPower.com 7
8/25/2016 MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.
© 2016 MPS. All Rights Reserved.
TM
OPERATION
The MPQ8039 is a general purpose, power
driver. It takes a logic input and drives a half
bridge comprised of 0.1Ω high-side and
low-side N-Channel MOSFET switches.
It operates at frequencies up to 1.2MHz, can
accept a DC supply voltage as high as 25V,
and produce peak output current as high as 9A.
Figure 1: Function Block Diagram
SW Output
The SW output drives the load. It is controlled
by the logic input signal at PWM. When the
signal at PWM is high (above 2V), the high-side
switch is turned on. When the signal at PWM is
low (less than 0.4V), the low-side switch is
turned on.
The MPQ8039 uses internal N-Channel
MOSFETs for both the high-side and low-side
switches. The high-side MOSFET gate drive is
powered from the voltage between SW and BS,
allowing BS to rise above the SP input voltage
to power the high-side MOSFET. To do this a
bootstrap capacitor is connected between SW
and BS. When the low-side switch is on, the
capacitor is internally charged from the voltage
at DRV, which is also internally generated.
There is a dead time region (typically 40ns)
where both the upper and lower switches are
off (see Figure 2).
Both the high-side and low-side switches have
internal current limits to prevent failure due to
excessive load current. Once the current limit is
reached, both output switches are turned off
and the fault output is asserted (driven low).
Shutdown
The MPQ8039 includes a 2.5μA shutdown
mode. When SHDN is high, both output
switches are turned off and the input current
drops to 2.5μA. When the MPQ8039 is
shutdown, the internally generated voltage at
DRV drops to 0V. If the shutdown mode is not
used, connect SHDN directly to GND.
HI DRIVE
LO DRIVE
CURRENT
LIMIT &
FEEDBACK
BS
UVLO
THERMAL
SHUTDOWN
UVLO
INTERNAL
5V REG.
LOGIC
100kΩ
D
BS
6
1
7
5
2
3
4
DRV
PWM
SHDN
BS
SP
SW
GND
