ISL85418FRZ-T7A datasheet, PDF

Datasheet> All Categories > Power/power management> The power supply circuit> ISL85418FRZ-T7A

ISL85418FRZ-T7A: DescriptionIC REG BUCK ADJ 0.8A SYNC 12DFN; CategoryPower/power management The power supply circuit; File Size1MB，21 Pages; ManufacturerRenesas Electronics Corporation; Websitehttps://www.renesas.com/

Download Datasheet Parametric Compare View All

ISL85418FRZ-T7A Online Shopping

Suppliers	Part Number	Price	MOQ	In stock
	ISL85418FRZ-T7A	-	-	View	Buy Now

ISL85418FRZ-T7A Overview

IC REG BUCK ADJ 0.8A SYNC 12DFN

ISL85418FRZ-T7A Parametric

Parameter Name	Attribute value
Brand Name	Renesas
Parts packaging code	DFN
package instruction	,
Contacts	12
Manufacturer packaging code	L12.4X312
Reach Compliance Code	compliant
Analog Integrated Circuits - Other Types	SWITCHING REGULATOR
Base Number Matches	1

Preview

Download Datasheet

View All

DATASHEET

ISL85418

Wide V

800mA Synchronous Buck Regulator

The ISL85418 is a 800mA synchronous buck regulator with an

input range of 3V to 40V. It provides an easy to use, high

efficiency low BOM count solution for a variety of applications.

The ISL85418 integrates both high-side and low-side NMOS

FETs and features a PFM mode for improved efficiency at light

loads. This feature can be disabled if forced PWM mode is

desired. The part switches at a default frequency of 500kHz

but may also be programmed using an external resistor from

300kHz to 2MHz. The ISL85418 has the ability to utilize

internal or external compensation. By integrating both NMOS

devices and providing internal configuration options, minimal

external components are required, reducing BOM count and

complexity of design.

With the wide V

range and reduced BOM, the part provides

an easy to implement design solution for a variety of

applications while giving superior performance. It will provide

a very robust design for high voltage industrial applications as

well as an efficient solution for battery powered applications.

The part is available in a small Pb-free 4mmx3mm DFN plastic

package with an operation temperature range of -40°C to

+125°C.

FN8369

Rev 5.00

March 13, 2015

Features

• Wide input voltage range 3V to 40V

• Synchronous operation for high efficiency

• No compensation required

• Integrated high-side and low-side NMOS devices

• Selectable PFM or forced PWM mode at light loads

• Internal fixed (500kHz) or adjustable switching frequency

300kHz to 2MHz

• Continuous output current up to 800mA

• Internal or external soft-start

• Minimal external components required

• Power-good and enable functions available

Applications

• Industrial control

• Medical devices

• Portable instrumentation

• Distributed power supplies

• Cloud infrastructure

Related Literature

•

AN1905,

“ISL85410EVAL1Z, ISL85418EVAL1Z Wide V

1A,

800mA Synchronous Buck Regulator”

•

AN1908,

“ISL85410DEMO1Z, ISL85418DEMO1Z Wide V

1A, 800mA Synchronous Buck Regulator”

100

EFFICIENCY (%)

1 SS

SYNC

FS 12

COMP

GND

VCC

1µF

= 12V

= 5V

= 24V

= 15V

= 33V

BOOT

100nF

OUT

10µF

22µH

3 BOOT

VIN

10µF

4 VIN

5 PHASE

PGND

INTERNAL DEFAULT PARAMETER SELECTION

0.1

0.2

0.3

0.4

0.5

OUTPUT LOAD (A)

0.6

0.7

0.8

FIGURE 1. TYPICAL APPLICATION

FIGURE 2. EFFICIENCY vs LOAD, PFM, V

OUT

= 3.3V

FN8369 Rev 5.00

March 13, 2015

Page 1 of 21

ISL85418

Table of Contents

Pin Configuration. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

Pin Descriptions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

Typical Application Schematics. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

Functional Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Ordering Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Absolute Maximum Ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Thermal Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Recommended Operating Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Electrical Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Efficiency Curves . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

Measurements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

Detailed Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Power-On Reset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Soft-Start. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Power-Good . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

PWM Control Scheme . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Light Load Operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Output Voltage Selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Protection Features. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Overcurrent Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Negative Current Limit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Over-Temperature Protection. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Boot Undervoltage Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Application Guidelines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Simplifying the Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Operating Frequency . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Synchronization Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Output Inductor Selection. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Buck Regulator Output Capacitor Selection. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Loop Compensation Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Layout Considerations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Revision History. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

About Intersil . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

Package Outline Drawing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

FN8369 Rev 5.00

March 13, 2015

Page 2 of 21

ISL85418

Pin Configuration

ISL85418

(12 LD 4x3 DFN)

TOP VIEW

SS 1

SYNC 2

BOOT 3

VIN 4

PHASE 5

PGND 6

GND

12 FS

11 COMP

10 FB

VCC

Pin Descriptions

PIN NUMBER

SYMBOL

PIN DESCRIPTION

The SS pin controls the soft-start ramp time of the output. A single capacitor from the SS pin to ground

determines the output ramp rate. See

“Soft-Start” on page 14

for soft-start details. If the SS pin is tied to

VCC, an internal soft-start of 2ms will be used.

Synchronization and light load operational mode selection input. Connect to logic high or VCC for PWM

mode. Connect to logic low or ground for PFM mode. Logic ground enables the IC to automatically choose

PFM or PWM operation. Connect to an external clock source for synchronization with positive edge trigger.

Sync source must be higher than the programmed IC frequency. There is an internal 5MΩ pull-down resistor

to prevent an undefined logic state if SYNC is left floating.

Floating bootstrap supply pin for the power MOSFET gate driver. The bootstrap capacitor provides the

necessary charge to turn on the internal N-channel MOSFET. Connect an external 100nF capacitor from this

pin to PHASE.

The input supply for the power stage of the regulator and the source for the internal linear bias regulator.

Place a minimum of 4.7µF ceramic capacitance from VIN to GND and close to the IC for decoupling.

Switch node output. It connects the switching FETs with the external output inductor.

Power ground connection. Connect directly to the system GND plane.

Regulator enable input. The regulator and bias LDO are held off when the pin is pulled to ground. When the

voltage on this pin rises above 1V, the chip is enabled. Connect this pin to VIN for automatic start-up. Do not

connect EN pin to VCC since the LDO is controlled by EN voltage.

Open drain power-good output that is pulled to ground when the output voltage is below regulation limits

or during the soft-start interval. There is an internal 5MΩ internal pull-up resistor.

Output of the internal 5V linear bias regulator. Decouple to PGND with a 1µF ceramic capacitor at the pin.

Feedback pin for the regulator. FB is the inverting input to the voltage loop error amplifier. COMP is the

output of the error amplifier. The output voltage is set by an external resistor divider connected to FB. In

addition, the PWM regulator’s power-good and UVLO circuits use FB to monitor the regulator output voltage.

COMP is the output of the error amplifier. When it is tied to VCC, internal compensation is used. When only

an RC network is connected from COMP to GND, external compensation is used. See

“Loop Compensation

Design” on page 17

for more details.

Frequency selection pin. Tie to VCC for 500kHz switching frequency. Connect a resistor to GND for

adjustable frequency from 300kHz to 2MHz.

Signal ground connections. Connect to application board GND plane with at least 5 vias. All voltage levels

are measured with respect to this pin. The EPAD MUST NOT float.

SYNC

BOOT

VIN

PHASE

PGND

VCC

COMP

EPAD

GND

FN8369 Rev 5.00

March 13, 2015

Page 3 of 21

ISL85418FRZ-T7A Related Products

	ISL85418FRZ-T7A
Description	IC REG BUCK ADJ 0.8A SYNC 12DFN
Brand Name	Renesas
Parts packaging code	DFN
Contacts	12
Manufacturer packaging code	L12.4X312
Reach Compliance Code	compliant
Analog Integrated Circuits - Other Types	SWITCHING REGULATOR
Base Number Matches	1

Recommended Resources

Portable alcohol tester circuit diagram

Programmable ROM LED display

Lead acid battery charger circuit diagram

Microprocessor controlled relay circuit

AC current measurement circuit that maintains readings

Using integrated circuit 555 to form a multivibrator

Application of operational amplifier in current source: [align=left][color=#000] A current source cannot force current into a load without the necessary voltage. Think of a current source as a circuit that adjusts its output voltage to force the desired cu...; 模拟IC Analogue and Mixed Signal

How to set PHY-address?: I would like to ask if anyone has used a physical layer chip, such as RTL8212, how to set its PHY-ADDRESS, if not set, is it important? Thank you...; wenhuawu Embedded System

Problems with some GPRS modules connecting to WAP gateways: For my graduation project, I accepted a task to send MMS using GPRS module, and I read all the information I found online. 01 02 83 01 45 6E 63 6F 64 69 6E 67 2D 56 65 72 73 69 6F 6E 00 31 2E 32 00 80...; gw1300 Embedded System

Smart Community Network Alarm System Solution: In a smart community, a complete networked alarm system mainly includes: a user local alarm system, an alarm technology center, and a data exchange channel connecting the two. The user local alarm sys...; 探路者 Mobile and portable

Masters, let's take a look at the modified rectifier circuit: [i=s] This post was last edited by 181813753 on 2016-9-14 14:25 [/i] [color=#363636] As shown in the figure, yesterday's circuit is selected as follows, discard the small voltage group, and take C12 t...; 181813753 51mcu

Thank you for the forum prize: The 32g USB flash drive used in the forum is very good....; 青城山下 Talking

Shortcut: S0 S1 S2 S3 S4 S5 S6 S7 S8 S9 SA SB SC SD SE SF SG SH SI SJ SK SL SM SN SO SP SQ SR SS ST SU SV SW SX SY SZ T0 T1 T2 T3 T4 T5 T6 T7 T8 T9 TA TB TC TD TE TF TG TH TI TJ TK TL TM TN TO TP TQ TR TS TT TU TV TW TX TY TZ U0 U1 U2 U3 U4 U6 U7 U8 UA UB UC UD UE UF UG UH UI UJ UK UL UM UN UP UQ UR US UT UU UV UW UX UZ V0 V1 V2 V3 V4 V5 V6 V7 V8 V9 VA VB VC VD VE VF VG VH VI VJ VK VL VM VN VO VP VQ VR VS VT VU VV VW VX VY VZ W0 W1 W2 W3 W4 W5 W6 W7 W8 W9 WA WB WC WD WE WF WG WH WI WJ WK WL WM WN WO WP WR WS WT WU WV WW WY X0 X1 X2 X3 X4 X5 X7 X8 X9 XA XB XC XD XE XF XG XH XK XL XM XN XO XP XQ XR XS XT XU XV XW XX XY XZ Y0 Y1 Y2 Y4 Y5 Y6 Y9 YA YB YC YD YE YF YG YH YK YL YM YN YP YQ YR YS YT YX Z0 Z1 Z2 Z3 Z4 Z5 Z6 Z8 ZA ZB ZC ZD ZE ZF ZG ZH ZJ ZL ZM ZN ZP ZR ZS ZT ZU ZV ZW ZX ZY

Popular Components