ISL6558EVAL2 Intersil, ISL6558EVAL2 Datasheet - Page 3

• Manufacturer Part Number: ISL6558EVAL2
• Description: EVAL BOARD W/6605 DRVRS ISL6558
• Manufacturer: Intersil
• Series: Endura™r

Specifications of ISL6558EVAL2

• Main Purpose: DC/DC, Step Down
• Outputs And Type: 1, Non-Isolated
• Voltage - Output: 1.35V
• Current - Output: 30A
• Voltage - Input: 4.5 ~ 5.5V
• Regulator Topology: Buck
• Frequency - Switching: 500kHz
• Board Type: Fully Populated
• Utilized Ic / Part: HIP6609, ISL6558
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Power - Output: -

Summary of Design
Table 1 summarizes the specifications of a power converter
for mid-range router applications. The ISL6558 and ISL6609
based evaluation board has been designed to meet these
criteria.
Table 2 shows the calculation results of critical design
parameters for the reference design, a two-phase
interleaved DC/DC buck converter.
PARAMETER
Transient Regulation
Undervoltage Falling
Transient Slew Rate
Undervoltage Rising
Channel Switching
ESR(max)
Output Regulation
Cin (min)
Continuous Load
Lin (min)
Minimum Airflow
Co(min)
I
IN,RMS
Io
PARAMETER
Input Voltage
Over Current
Overvoltage
Fsw
RMS
Frequency
Threshold
Threshold
Threshold
D
Efficiency
DUTY CYCLE AND SWITCHING FREQUENCY
TABLE 2. CRITICAL DESIGN PARAMETERS
TABLE 1. ISL6558EVAL2 SPECIFICATIONS
INPUT INDUCTOR AND CAPACITORS
V
RT = 51.1kΩ (measured)
Io = 30A
V
Cin = 180µFx3, dIin/dt = 0.1A/µs
f
Lo(Io) = 0.3µH,
Istep = 6.5A, f(step) = 20mV
c
IN
IN
= Fsw/5 = 100kHz, f(Istep)
= 5, Vo = 1.35
= 5.5V, Io = 30A
OUTPUT CAPACITORS
25°C with No
CONDITION
,
0.1% R16
6.5A Step
25°C with
25°C with
25°C with
N = 2, ∆V
and R19
200A/µs
200LFM
200LFM
200LFM
Airflow
CONDITIONS
VIN
V
IN = 5.5V
3
IN,CAP
20mV
1.336
4.5V
MIN
Vo -
= 20mV
=
20mV
200A/µs
500kHz
0.92Vo
1.15Vo
0 LFM
89.7%
89.3%
0.9Vo
TYP
1.35
30A
43A
5V
VALUE UNIT
Application Note 1044
28.3
7.63
1.34
3.07
500
180
300
517
20mV
1.365
MAX
5.5V
Vo +
kHz
mΩ
nH
µF
µF
%
A
A
Table 3 summarizes a rough power dissipation analysis for
the referenced design.
PARAMETER
Switching Frequency
Per-Channel Output
Inductor
Number of Active Channels
Upper FETs Conduction
Upper FETs Switching
Lower FETs Conduction
Lower FETs Body-diode
Conduction
Output Inductor Copper
Output Inductor Core
(Estimated)
Per-Channel Driver
Input Inductors Copper
Input Inductors Core
Input Capacitors
Output Capacitors
Controller
PCB Copper
Miscounted and Error
OUTPUT INDUCTORS (ASSUMING EQUAL DISTRIBUTION
I
I
I
I
Q1,RMS
Q1,RMS
TABLE 2. CRITICAL DESIGN PARAMETERS (Continued)
Lo,Peak
Lo,RMS
I
Lo,PP
TABLE 3. FULL-LOAD POWER DISSIPATION BUDGET
I
PP
ELEMENTS
TOTAL
Lo(Io) = 0.3µH, V
Lo(Io) = 0.3µH, V
Lo(Io) = 0.3µH, V
Lo(Io) = 0.3µH, V
Lo(Io) = 0.3µH, V
Lo(Io) = 0.3µH, V
AMONG OUTPUT INDUCTORS)
PER-CHANNEL LOSSES (xN)
CALCULATION CONDITIONS
CONDITIONS
LOWER FETs
OTHERS (x1)
UPPER FETs
POWER DISSIPATION AT 30A LOAD
0.0035W
0.395W
0.461W
0.333W
0.233W
0.123W
0.036W
0.305W
0.055W
0.273W
0.078W
0.196W
4.655W
0.32W
IN
IN
IN
IN
IN
IN
4.5V
= 5.5V
= 5.5V, N = 2
= 5.5V
= 5.5V
= 4.5V
= 5.5V
0.3µH at Full load
Negligible
0.0.036W
0.0048W
500kHz
0.356W
0.516W
0.328W
0.232W
0.123W
0.375W
0.044W
0.287W
0.078W
0.184W
4.688W
0.28W
N = 2
5.0V
VALUE UNIT
18.44
15.13
13.04
6.88
4.65
8.48
0.0061W
0.323W
0.572W
0.340W
0.231W
0.123W
0.036W
0.454W
0.037W
0.291W
0.078W
0.176W
4.737W
April 4, 2006
0.29W
5.5V
AN1044.2
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