ISL6529CR Intersil, ISL6529CR Datasheet - Page 13

• Manufacturer Part Number: ISL6529CR
• Description: IC CTRLR PWM DUAL REG 16-QFN
• Manufacturer: Intersil
• Type: Step-Down (Buck)r

Specifications of ISL6529CR

• Internal Switch(s): No
• Synchronous Rectifier: Yes
• Number Of Outputs: 2
• Voltage - Output: 0.5 ~ 4.5 V
• Frequency - Switching: 600kHz
• Operating Temperature: 0°C ~ 70°C
• Mounting Type: Surface Mount
• Package / Case: 16-VQFN Exposed Pad, 16-HVQFN, 16-SQFN, 16-DHVQFN
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Current - Output: -
• Voltage - Input: -
• Power - Output: -

frequencies and high load current. Figure 13 shows the
results of the complete system with output capacitor and
compensation network for 45° of phase margin.
Because of the large variety of capacitors, varying ESRs and
PC board layouts, Table 1, based upon system simulations
is provided as a starting point guide to aid in the selection of
compensation networks for output capacitors values of 1µF,
10µF, 100µF and 1000µF with ESR values of 5mΩ, 30mΩ
and 100mΩ for each capacitor value. The frequencies
100mΩ
30mΩ
5mΩ
CAP
ESR
Low Fq Zero (C4 & R12)
Midband Gain R12/R5
Midband Gain R12/R5
MidbandGain R12/R5
Pole (C16 & R12)
Pole (C16 & R12)
Pole (C16 & R12)
Zero (C4 & R12)
Zero (C4 & R12)
& ESR Zero Fq
& ESR Zero Fq
& ESR Zero Fq
OUTPUT CAP
OUTPUT Cap
OUTPUT Cap
Network
Network
Network
High Fq
High Fq
High Fq
DETAIL
Low Fq
Low Fq
Comp
Comp
Comp
13
TABLE 1. COMPENSATION NETWORKS FOR LINEAR REGULATOR
C16 = 10pF
C4 = 200pF
C16 = 10pF
C4 = 200pF
C16 = 10pF
C4 = 200pF
R12 = 47K
R12 = 47K
R12 = 47K
338kHz
338kHz
5.3MHz
338kHz
1.6MHz
32MHz
17kHz
17kHz
17kHz
20dB
20dB
20dB
1µF
ISL6529, ISL6529A
C16 = 10pF
C4 = 470pF
C16 = 10pF
C4 = 470pF
C16 = 10pF
C4 = 470pF
R12 = 47K
R12 = 47K
R12 = 47K
associated with the compensation elements are also shown
to aid in component selection.
Parallel capacitors of the same value and type can be
treated as a combination. For example three 100µF, 10mΩ
capacitors may be treated as one 300µF, 3.3mΩ capacitor.
Mixed capacitors require more attention. For example the
compensation for a 1000µF, low ESR capacitor will suffice
for a shunting 10µF, low ESR capacitor.
338kHz
3.2MHz
338kHz
530kHz
338kHz
160kHz
7.2kHz
17kHz
17kHz
10µF
20dB
20dB
20dB
OUTPUT CAPACITOR
C16 = 10pF
R12 = 200K
C4 = 470pF
C16 = 10pF
R12 = 200K
C4 = 470pF
C16 = 10pF
320kHz
1.7kHz
1.7kHz
100µF
80kHz
80kHz
53kHz
16kHz
33dB
33dB
-
-
-
C16 = 10pF
R12 = 470K
C4 = 470pF
C16 = 10pF
C16= 10pF
1000µF
5.3kHz
1.6kHz
720Hz
34kHz
32kHz
40dB
-
-
-
-
-
-
April 12, 2005
FN9070.5