ADP3611JRMZ-REEL ON Semiconductor, ADP3611JRMZ-REEL Datasheet - Page 9

• Manufacturer Part Number: ADP3611JRMZ-REEL
• Description: IC MOSFET DRIVER DUAL 10-MSOP
• Manufacturer: ON Semiconductor
• Type: High Side/Low Sider

Specifications of ADP3611JRMZ-REEL

• Configuration: High and Low Side, Synchronous
• Input Type: PWM
• Delay Time: 30ns
• Current - Peak: 25A
• Number Of Configurations: 1
• Number Of Outputs: 2
• Voltage - Supply: 4.6 V ~ 5.5 V
• Operating Temperature: -10°C ~ 100°C
• Mounting Type: Surface Mount
• Package / Case: 10-MSOP, Micro10™, 10-uMAX, 10-uSOP
• Product: MOSFET Gate Drivers
• Propagation Delay Time: 20 ns
• Supply Voltage (max): 5.5 V
• Supply Voltage (min): 4.6 V
• Supply Current: 1 mA
• Maximum Operating Temperature: + 100 C
• Mounting Style: SMD/SMT
• Minimum Operating Temperature: - 10 C
• Number Of Drivers: 2
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• High Side Voltage - Max (bootstrap): -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

driving two N-channel MOSFETs in a synchronous buck
converter topology. A single PWM input signal is all that
is required to properly drive the high-side and the low-side
MOSFETs. Each driver is capable of driving a 3 nF load at
speeds up to 1 MHz. A more detailed description of the
ADP3611 and its features follows. Refer to the detailed
block diagram in Figure 18.
Undervoltage Lockout
MOSFET driver outputs low during VCC supply ramp-up.
The UVLO logic becomes active and in control of the
driver outputs at a supply voltage of no greater than 1.5 V.
The UVLO circuit waits until the VCC supply has reached
a voltage high enough to bias logic level MOSFETs fully
on before releasing control of the drivers to the control pins.
Driver Control Input
ratio modulation signal of a switch-mode controller. IN can
be driven by 2.5 V to 5.0 V logic. The output MOSFETs are
driven so that the SW node follows the polarity of IN.
Low−Side Driver
referenced low R
MOSFET. The bias to the low-side driver is internally
connected to the VCC supply and GND. Once the supply
voltage ramps up and exceeds the UVLO threshold, the
driver is enabled. When the driver is enabled, the driver’s
output is 180° out of phase with the IN pin. Table 5 shows
the relationship between DRVL and the different control
inputs of the ADP3611.
The ADP3611 is a dual MOSFET driver optimized for
The undervoltage lockout (UVLO) circuit holds both
The driver control input (IN) is connected to the duty
The low-side driver is designed to drive a ground-
Figure 18. Detailed Block Diagram of the ADP3611
DS(ON)
N-channel synchronous rectifier
THEORY OF OPERATION
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9
High−Side Driver
R
high-side driver is developed by an external bootstrap
supply circuit, which is connected between the BST and
SW pins.
bootstrap capacitor, C
up, the SW pin is at ground, so the bootstrap capacitor
charges up to VCC through D1. Once the supply voltage
ramps up and exceeds the UVLO threshold, the driver is
enabled. When IN goes high, the high-side driver begins to
turn on the high-side MOSFET (Q1) by transferring charge
from C
forcing the BST pin to V
gate-to-source voltage to hold Q1 on. To complete the
cycle, Q1 is switched off by pulling the gate down to the
voltage at the SW pin. When the low-side MOSFET (Q2)
turns on, the SW pin is pulled to ground. This allows the
bootstrap capacitor to charge up to VCC again.
with the IN pin. Table 5 shows the relationship between
DRVH and the different control inputs of the ADP3611.
Overlap Protection Circuit
switches, Q1 and Q2, from being on at the same time. This
is done to prevent shoot-through currents from flowing
through both power switches and the associated losses that
can occur during their on-off transitions. The overlap
protection circuit accomplishes this by adaptively
controlling the delay from Q1’s turn-off to Q2’s turn-on,
and the delay from Q2’s turn-off to Q1’s turn-on.
turn-off and Q2’s turn-on, the overlap circuit monitors the
voltage at the SW pin and DRVH pin. When IN goes low,
Q1 begins to turn off. The overlap protection circuit waits
for the voltage at the SW and DRVH pins to both fall below
1.6 V. Once both of these conditions are met, Q2 begins to
turn on. Using this method, the overlap protection circuit
ensures that Q1 is off before Q2 turns on, regardless of
variations in temperature, supply voltage, gate charge, and
drive current. There is, however, a timeout circuit that
overrides the waiting period for the SW and DRVH pins to
reach 1.6 V. After the timeout period has expired, DRVL is
asserted high regardless of the SW and DRVH voltages. In
the opposite case, when IN goes high, Q2 begins to turn off
after a propagation delay. The overlap protection circuit
waits for the voltage at DRVL to fall below 1.6 V, after
which DRVH is asserted high and Q1 turns on.
Low−Side Driver Shutdown
signal to shut down the synchronous rectifier. Under light
load conditions, DRVLSD should be pulled low before the
DS(ON)
The high-side driver is designed to drive a floating low
The bootstrap circuit comprises a diode, D1, and
When the driver is enabled, the driver’s output is in phase
The overlap protection circuit prevents both main power
To prevent the overlap of the gate drives during Q1’s
The low-side driver shutdown DRVLSD allows a control
BST
N-channel MOSFET. The bias voltage for the
. As Q1 turns on, the SW pin rises up to V
BST
DCIN
. When the ADP3611 is starting
+ V
C(BST)
, which is enough
DCIN
,