Page 1
Application Note 1366
ISL8014AEVAL2Z: 4A Low Quiescent Current 1MHz
High Efficiency Synchronous Buck Regulator
Description
The ISL8014AEVAL2Z kit is intended for use by
individuals with requirements for Point-of-Load
applications sourcing from 2.7V to 5.5V. The
ISL8014AEVAL2Z evaluation board demonstrates the
performance of the ISL8014A low quiescent current
mode converter.
The ISL8014A is offered in a 4mmx4mm 16 Ld QFN
package with 1mm maximum height. The ISL8014A is
pin-to-pin compatible to the ISL8013A. The complete
converter occupies less than 0.4in
2
area.
Key Features
• High Efficiency Synchronous Buck Regulator with up
to 95% Efficiency
• Power-Good (PG) Output with 1ms Delay
• 2.7V to 5.5V Supply Voltage
• 3% Output Accuracy Over-Temperature/Load/Line
• 4A Guaranteed Output Current
• Start-up with Pre-biased Output
• Internal Digital Soft-Start - 1ms
• Soft-Stop Output Discharge During Disabled
• 35µA Quiescent Supply Current in PFM Mode
• Selectable Forced PWM Mode and PFM Mode
• External Synchronization up to 4MHz
• Less than 1µA Logic Controlled Shutdown Current
• 100% Maximum Duty Cycle for Lowest Dropout
• Internal Current Mode Compensation
• Peak Current Limiting and Hiccup Mode Short Circuit
Protection
• Over-Temperature Protection
Recommended Equipment
The following materials are recommended to perform
testing:
• 0V to 10V Power Supply with at least 5A Source
Current Capability or 5V Battery
• Electronic Loads Capable of Sinking Current Up to 5A
• Digital Multimeters (DMMs)
• 100MHz Quad-trace Oscilloscope
• Signal Generator
Quick Setup Guide
1. Ensure that the circuit is correctly connected to the
supply and loads prior to applying any power.
2. Connect the bias supply to VIN. Plus terminal to P4
(VIN) and negative return to P5 (GND).
3. Verify that position is ON for SW1.
4. Turn on the power supply.
5. Verify the output voltage is 1.8V for V
Evaluating the Other Output Voltage
The ISL8014AEVAL2Z kit output is preset to 1.8V;
however, output voltages can be adj usted from 0 .8V to
3.3V using Equations 1 and 2:
R
⎛⎞
1
V
=
OUT
Let’s set R
------------------------------ -
=
R
2
V
OUT
⎛⎞
--------------- -
⎝⎠
0.8
-------
0.8 1
+
⎜⎟
R
⎝⎠
= 124kΩ
1
R1()
1–
2
Note: If desired output is 0.8V, then short R
R2.
Mode Control
The ISL8014A has a SKIP pin that controls the operation
mode. When the SKIP pin is driven to low or shorted to
ground, the regulator operates in a PFM mode. Set SKIP
pin high forced PWM mode. The controller remains in the
fixed PWM frequency at light load instead of entering the
skip mode. In an application where situations require the
ISL8014A regulator to sink more than 2A valley inductor
current, it is recommended to operate in PFM to avoid
any possible over stress.
TABLE 1. SWITCH 1 SETTINGS
SW1 ENABLE ON/OFF CONTROL
1OFFDisable V
3ONEnable V
SW2 SKIP FUNCTION
1 PWM Fixed PWM frequency at light load
3 PFM Force continuous mode
OUT
OUT
OUT
and open
1
(EQ. 1)
(EQ. 2)
December 16, 2009
AN1366.3
1
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 registered trademark of Intersil Americas Inc.
Copyright Intersil Americas Inc. 2007, 2008, 2009. All Rights Reserved
All other trademarks mentioned are the property of their respective owners.
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Application Note 1366
ISL8014AEVAL2Z Schematic
VIN
P4
P5
1
1
C1
22µF
22
1
P3
22µF
1
C2
VIN
A
100k
PG1
OPEN
2
R4
1
2
1
R10
1
C3
2
SYNCH
17
A
21
D1
31
1
NC LX LX NC
1
VIN
2
VIN
3
VDD
ISL8014AIRZ
4
SYNCH
EP
EN PG
5 78
2
R5
2k
2N7002
Q1
2
A
J1
PGND
PGND
U1
SGND
SGND
NC FB
6
A
SYNCH
P2
43
13141516
1
1
2
VIN
100k
OPEN
J2
A
LX
12
11
10
9
2
R6
1
2
2
R9
1
L1
1.5µH
A
3
SW2
1
R1
124k
R2
100k
PWM
A
VOUT
2
1
2
1
1
C4
47pF
2
A
P6
1
C5
22µF
2
VIN
2
R7
100k
EN
1
2
R8
OPEN
1
1
43
2
1
1
C6
22µF
1
2
A
1
3
2
SW1
1
P7
P8
ON
OFFPFM
A
NOTE: Pins 13 and 16 are no connect pins which can tie to VIN, SGND, or LX.
Recommend connecting pin 13 to LX for compatibility to ISL8013.
2
December 16, 2009
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Application Note 1366
ISL8014AEVAL2Z Bill of Materials
REFERENCE
PART NUMBER QTY
ISL8014AEVAL2Z 1 PWB-PCB, ISL8014AEVAL2Z,
H1045-00470-50V5- T 1 C4 CAP , SMD , 0 603, 47pF, 50V, 5 %,
H1045-DNP 0 C3 CAP, SMD, 0603, DNP-PLACE
H1065-00226-6R3V10-T 4 C1, C2, C5, C6 CAP, SMD, 1206, 22µF, 6.3V,
DR73-1R5-R 1 L1 COIL-PWR INDUCTOR, SMD,
131-4353-00 2 J1, J2 CONN-SCOPE PROBE TEST PT,
1514-2 4 P4, P5, P7, P8 CONN-TURRET, TERMINAL POST,
5002 3 P2, P3, P6 CONN-MINI TEST POINT,
LTST-C170CKT 1 D1 LED-GaAs RED, SMD,
ISL8014AIRZ 1 U1 IC-4A, 1MHz, BUCK REGULA TOR,
2N7002-7-F- T 1 Q1 TRANSISTOR, N-CHANNEL, 3LD ,
H2511-00R00-1/10W-T 1 R10 RESISTOR, SMD, 0603, 0Ω,
H2511-01003-1/10W1-T 4 R2, R4, R6, R7 RES, SMD, 0603, 100k, 1/10W,
H2511-01243-1/10W1-T 1 R1 RES, SMD, 0603, 124k, 1/10W,
H2511-02 001-1/10W 1-T 1 R5 RES, SMD, 0603, 2k, 1/10W , 1%,
H2511-DNP 0 R8, R9 RES, SMD, 0603, DNP-PLACE
GT11MSCBE-T 2 SW1, SW2 SWITCH-TOGGLE, SMD,
LABEL-SERIAL NUMBER 1 LABEL, FOR SERIAL NUMBER
DESIGNATOR DESCRIPTION MANUFACTURER MANUFACTURER PART
REVA, ROHS
NPO, ROHS
HOLDER, ROHS
10%, X5R, ROHS
7.5mm, 1.5µH, 20%, 6.52A,
ROHS
COMPACT, PCB MNT, ROHS
TH, ROHS
VERTICAL, WHITE, ROHS
2mmx1.25mm, 100mW, 40mA,
10mcd, ROHS
16P, QFN, 4x4, ROHS
SOT-23, 60V, 115mA, ROHS
1/10W, TF, ROHS
1%, TF, ROHS
1%, TF, ROHS
TF, ROHS
HOLDER, ROHS
ULTRAMINI, 1P, SPST MINI
AND BOM REV #
ISL8014AEVAL2ZREVAPCB
AVX 06035A470JAT2A
PHILLIPS 0603X7R500-562KNE
MURATA GRM31CR60J226KE19L
KEMET C1206C226K9PACTU
AVX 12066D226KAT2A
COOPER ELECTRONIC
TECH.
TEKTRONIX 131-4353-00
KEYSTONE 1514-2
KEYSTONE 5002
LITEON/VISHAY LTST-C170CKT
ROHM SML-210LTT86
STANLEY ELECTRIC BR112H-TR
INTERSIL ISL8014AIRZ
DIODES, INC. 2N7002-7-F
ON SEMICONDUCTOR 2N7002LT1G
YAGEO 9C06031A1243FKHFT
PANASONIC ERJ-3EK1243V
KOA RK73H1JTTD2001F
VENKEL CR0603-10W-2001FT
C&K COMPONENTS GT11MSCKE
DR73-1R5-R
3
December 16, 2009
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Page 4
Application Note 1366
ISL8014AEVAL2Z Board Layout
ISL8014AEVAL2Z
FIGURE 1. TOP COMPONENTS
4
FIGURE 2. TOP LAYER ETCH
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Application Note 1366
ISL8014AEVAL2Z Board Layout (Continued)
FIGURE 3. 2ND LAYER ETCH
5
FIGURE 4. 3RD LAYER ETCH
December 16, 2009
AN1366.3
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Application Note 1366
ISL8014AEVAL2Z Board Layout (Continued)
FIGURE 5. BOTTOM LAYER COMPONENTS (MIRRORS)
Intersil Corporation reserves the right to make changes in circuit design, software and/or specifications at any time without notice. Accordingly, the
reader is cautioned to verify that the Applica tio n No te or Tec hnical Brief is current before proceeding.
For information regarding Intersil Corporation and its products, see www.intersil.com
6
FIGURE 6. BOTTOM LAYER ETCH (MIRROR)
December 16, 2009
AN1366.3
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