LM5110-1/2/3M National Semiconductor Corporation, LM5110-1/2/3M Datasheet - Page 8

• Manufacturer Part Number: LM5110-1/2/3M
• Description: Dual 5A Compound Gate Driver With Negative Output Voltage Capabilitythe LM5110 Dual Gate Driver Replaces Industry Standard Gate Drivers With Improved Peak Output Current And Efficiency. Each "compound" Output Driver Stage Includes MOS And Bipolar Tra
• Manufacturer: National Semiconductor Corporation

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Typical Performance Characteristics
Detailed Operating Description
LM5110 dual gate driver consists of two independent and
identical driver channels with TTL compatible logic inputs
and high current totem-pole outputs that source or sink
current to drive MOSFET gates. The driver output consist of
a compound structure with MOS and bipolar transistor oper-
ating in parallel to optimize current capability over a wide
output voltage and operating temperature range. The bipolar
device provides high peak current at the critical threshold
region of the MOSFET VGS while the MOS devices provide
rail-to-rail output swing. The totem pole output drives the
MOSFET gate between the gate drive supply voltage V
and the power ground potential at the V
The control inputs of the drivers are high impedance CMOS
buffers with TTL compatible threshold voltages. The nega-
tive supply of the input buffer is connected to the input
ground pin IN_REF. An internal level shifting circuit connects
the logic input buffers to the totem pole output drivers. The
level shift circuit and separate input/output ground pins pro-
vide the option of single supply or split supply configurations.
When driving MOSFET gates from a single positive supply,
the IN_REF and V
Delay Time vs Temperature
EE
pins are both connected to the power
UVLO Thresholds and Hysteresis vs Temperature
EE
pin.
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(Continued)
ground. The LM5110 pinout was designed for compatibility
with industry standard gate drivers in single supply gate
driver applications. Pin 1 (IN_REF) on the LM5110 is a
no-connect on standard driver IC’s. Connecting pin 1 to pin 3
(V
of both the LM5110 and competitive drivers.
The isolated input/output grounds provide the capability to
drive the MOSFET to a negative VGS voltage for a more
robust and reliable off state. In split supply configuration, the
IN_REF pin is connected to the ground of the controller
which drives the LM5110 inputs. The V
a negative bias supply that can range from the IN-REF as
much as 14V below the V
mum recommended voltage difference between V
IN_REF or between V
voltage difference between V
Enhancement mode MOSFETs do not inherently require a
negative bias on the gate to turn off the FET. However,
certain applications may benefit from the capability of nega-
tive VGS voltage during turn-off including:
1. when the gate voltages cannot be held safely below the
EE
threshold voltage due to transients or coupling in the
printed circuit board.
) on the printed circuit board accommodates the pin-out
RDSON vs Supply Voltage
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CC
and V
CC
gate drive supply. The maxi-
and IN_REF is 3.5V.
EE
is 14V. The minimum
EE
pin is connected to
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and