1

2.5A Regulator with Integrated High-Side MOSFET for

Synchronous Buck or Boost Buck Converter

ISL78200

The ISL78200 is a synchronous buck controller with a 90mΩ

high-side MOSFET and low-side driver integrated. The ISL78200

supports wide input range of 3V to 40V in buck mode. It supports

8V to 36V, 500kHz and +85°C ambient temperature with still air.

For any specific application, the actual maximum output current

depends upon the die temperature not exceeding +125°C with

the power dissipated in the IC, which is related to input voltage,

output voltage, duty cycle, switching frequency, ambient

temperature and board layout, etc. Refer to section “Output

Current” on page 14 for more details.

The ISL78200 has flexible selection of operation modes of forced

PWM mode and PFM mode. In PFM mode, the quiescent input

current is as low as 300µA and can be further reduced to 180µA

application. The load boundary between PFM and PWM can be

programmed to cover wide applications.

The low-side driver can be either used to drive an external low-side

MOSFET for a synchronous buck, or left unused for a standard

non-synchronous buck. The low-side driver can also be used to

drive a boost converter as a pre-regulator that greatly expands the

operating input voltage range down to 2.5V or lower (refer to

“Typical Application Schematic III - Boost Buck Converters” on

page 5).

The ISL78200 offers the most robust current protections. It uses

peak current mode control with cycle-by-cycle current limiting. It is

implemented with frequency foldback under current limit

condition; in addition, the hiccup overcurrent mode is also

implemented to guarantee reliable operations under harsh short

conditions.

The ISL78200 has comprehensive protections against various faults

including overvoltage and over-temperature protections, etc.

Features

• Buck Mode: Input Voltage Range 3V to 40V (Refer to “Input

Voltage” on page 14 for more details)

• Boost Mode Expands Operating Input Voltage Lower Than

2.5V (Refer to “Input Voltage” on page 14 for more details)

• Selectable Forced PWM Mode or PFM Mode

• 300µA IC Quiescent Current (PFM, No Load); 180µA Input

• Less than 3µA Shut Down Input Current (IC Disabled)

• Operational Topologies

-Synchronous Buck

-Non-Synchronous Buck

-Two Stage Boost Buck

• Programmable Frequency from 200kHz - 2.2MHz and

Frequency Synchronization Capability

• Reliable Cycle-by-Cycle Overcurrent Protection

- Temperature Compensated Current Sense

- Frequency Foldback

- Programmable OC Limit

-Hiccup Mode Protection in Worst Case Short Condition

• 20 Ld HTSSOP Package

• AEC Q100 Qualified

• Pb-Free (RoHS Compliant)

Applications

• Automotive Applications

• General Purpose Power Regulator

• 24V Bus Power

•Battery Power

• Embedded Processor and I/O Supplies

FIGURE 1. TYPICAL APPLICATION

FIGURE 2. EFFICIENCY, SYNCHRONOUS BUCK, PFM MODE,

VOUT

ISL78200

VCC

SGND

MODE

BOOT

VIN

PHASE

PGND

FS

EXT_BOOST

EN

FB

COMP

VIN

AUXVCC

LGATE

ILIMIT

SS

SYNC

PGOOD

50

55

60

65

70

75

80

85

90

95

100

0.1m

1m

10m

100m

1

2.5

LOAD CURRENT (A)

December 24, 2013

FN7641.2

CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures.

1-888-INTERSIL or 1-888-468-3774

Intersil (and design) is a trademark owned by Intersil Corporation or one of its subsidiaries.

All other trademarks mentioned are the property of their respective owners.

NOT RECOM

MENDED FO

R NEW DES

IGNS

RECOMMEN

DED REPLA

CEMENT PA

RT

ISL78201