DATASHEET
ISL78322
FN7908
Rev 3.00
November 30, 2016
Dual 2A/1.7A, 2.25MHz High-Efficiency, Synchronous Buck Regulator
The ISL78322 is a high-efficiency, dual synchronous step-down
Features
DC/DC regulator that can deliver up to 2A/1.7A continuous
• Dual 2A/1.7A high-efficiency, synchronous buck regulator
with up to 97% efficiency
output current per channel. The channels are 180° out-of-
phase for input RMS current and EMI reduction. The supply
voltage range of 2.8V to 5.5V allows for the use of a single Li+
cell, three NiMH cells or a regulated 5V input. The current
mode control architecture enables very low duty cycle
operation at high frequency with fast transient response and
excellent loop stability. The ISL78322 operates at 2.25MHz
switching frequency, which allows for the use of small, low cost
inductors and capacitors. Each channel is optimized for
generating an output voltage as low as 0.6V.
• 2.8V to 5.5V input supply range
• 180° out-of-phase outputs reduce ripple current and EMI
• Start-up with prebiased output prevents negative current
flow in output stage
• External synchronization up to 8MHz
• Negative current detection and protection
• 100% maximum duty cycle for lowest dropout
• Internal current mode compensation
The ISL78322 has a forced PWM mode that reduces noise and
RF interference.
• Peak current limiting, hiccup mode short-circuit protection,
and over-temperature protection
The ISL78322 offers a 1ms Power-Good (PG) signal to monitor
both outputs at power-up. When shut down, ISL78322
discharges the output capacitors. Other features include
internal digital soft-start, enable for power sequence,
• Pb-free (RoHs compliant)
• AEC-Q100 qualified component
overcurrent protection, and thermal shutdown. The ISL78322
is offered in a 4mmx3mm, 12 Lead DFN package with 1mm
maximum height. The complete converter occupies less than
Applications
• DC/DC POL modules
2
1.8cm area.
• µC/µP, FPGA, and DSP power
• Automotive embedded processor power supply systems
The ISL78322 is qualified to AEC-Q100 and specified for
operation across the -40°C to +105°C (grade 2) ambient
temperature range.
Related Literature
• For a full list of related documents, visit our website
- ISL78322 product page
100
90
80
2.5V
PWM
OUT1
3.3V
PWM
OUT2
70
60
50
40
2.25MHz 5V AT +25°C
IN
0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
OUTPUT LOAD (A)
FIGURE 1. CHARACTERISTIC CURVE
FN7908 Rev 3.00
November 30, 2016
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