Electronic Components Datasheet Search
  English  ▼
ALLDATASHEET.NET

X  

ISL6532CR Datasheet(PDF) 11 Page - Renesas Technology Corp

Part # ISL6532CR
Description  ACPI Regulator/Controller for Dual Channel DDR Memory Systems
Download  15 Pages
Scroll/Zoom Zoom In 100%  Zoom Out
Manufacturer  RENESAS [Renesas Technology Corp]
Direct Link  http://www.renesas.com
Logo RENESAS - Renesas Technology Corp

ISL6532CR Datasheet(HTML) 11 Page - Renesas Technology Corp

Back Button ISL6532CR Datasheet HTML 7Page - Renesas Technology Corp ISL6532CR Datasheet HTML 8Page - Renesas Technology Corp ISL6532CR Datasheet HTML 9Page - Renesas Technology Corp ISL6532CR Datasheet HTML 10Page - Renesas Technology Corp ISL6532CR Datasheet HTML 11Page - Renesas Technology Corp ISL6532CR Datasheet HTML 12Page - Renesas Technology Corp ISL6532CR Datasheet HTML 13Page - Renesas Technology Corp ISL6532CR Datasheet HTML 14Page - Renesas Technology Corp ISL6532CR Datasheet HTML 15Page - Renesas Technology Corp  
Zoom Inzoom in Zoom Outzoom out
 11 / 15 page
background image
ISL6532
FN9112 Rev 4.00
Page 11 of 15
Sep 12, 2013
Modulator Break Frequency Equations
The compensation network consists of the error amplifier
(internal to the ISL6532) and the impedance networks ZIN and
ZFB. The goal of the compensation network is to provide a
closed loop transfer function with the highest 0dB crossing
frequency (f0dB) and adequate phase margin. Phase margin is
the difference between the closed loop phase at f0dB and 180
degrees. The equations below relate the compensation
network’s poles, zeros and gain to the components (R1, R2,
R3, C1, C2, and C3) in Figure 5. Use these guidelines for
locating the poles and zeros of the compensation network:
1. Pick Gain (R2/R1) for desired converter bandwidth.
2. Place 1ST Zero Below Filter’s Double Pole (~75% FLC).
3. Place 2ND Zero at Filter’s Double Pole.
4. Place 1ST Pole at the ESR Zero.
5. Place 2ND Pole at Half the Switching Frequency.
6. Check Gain against Error Amplifier’s Open-Loop Gain.
7. Estimate Phase Margin - Repeat if Necessary.
Compensation Break Frequency Equations
Figure 6 shows an asymptotic plot of the DC-DC converter’s
gain vs. frequency. The actual Modulator Gain has a high gain
peak due to the high Q factor of the output filter and is not
shown in Figure 6. Using the above guidelines should give a
Compensation Gain similar to the curve plotted. The open loop
error amplifier gain bounds the compensation gain. Check the
compensation gain at FP2 with the capabilities of the error
amplifier. The Closed Loop Gain is constructed on the graph of
Figure 6 by adding the Modulator Gain (in dB) to the
Compensation Gain (in dB). This is equivalent to multiplying
the modulator transfer function to the compensation transfer
function and plotting the gain.
The compensation gain uses external impedance networks
ZFB and ZIN to provide a stable, high bandwidth (BW) overall
loop. A stable control loop has a gain crossing with
-20dB/decade slope and a phase margin greater than 45
degrees. Include worst case component variations when
determining phase margin.
Output Voltage Selection
The output voltage of the VDDQ PWM converter can be
programmed to any level between VIN and the internal
reference, 0.8V. An external resistor divider is used to scale
the output voltage relative to the reference voltage and feed it
back to the inverting input of the error amplifier, see Figure 6.
However, since the value of R1 affects the values of the rest of
the compensation components, it is advisable to keep its value
less than 5kW. Depending on the value chosen for R1, R4 can
be calculated based on the following equation:
If the output voltage desired is 0.8V, simply route VDDQ back
to the FB pin through R1, but do not populate R4.
The output voltage for the internal VTT linear regulator is set
internal to the ISL6532 to track the VDDQ voltage by 50%.
There is no need for external programming resistors.
Component Selection Guidelines
Output Capacitor Selection - PWM Buck Converter
An output capacitor is required to filter the inductor current and
supply the load transient current. The filtering requirements are
a function of the switching frequency and the ripple current.
The load transient requirements are a function of the slew rate
(di/dt) and the magnitude of the transient load current. These
requirements are generally met with a mix of capacitors and
careful layout.
DDR memory systems are capable of producing transient load
rates above 1A/ns. High frequency capacitors initially supply the
transient and slow the current load rate seen by the bulk
capacitors. The bulk filter capacitor values are generally
determined by the ESR (Effective Series Resistance) and
voltage rating requirements rather than actual capacitance
requirements.
High frequency decoupling capacitors should be placed as
close to the power pins of the load as physically possible. Be
FLC
1
2
 x LO x CO
-------------------------------------------
=
FESR
1
2
 x ESR x CO
--------------------------------------------
=
FZ1
1
2
 x R
2 x C2
------------------------------------
=
FZ2
1
2
 x R
1
R3
+
 x C
3
-------------------------------------------------------
=
FP1
1
2
 x R
2 x
C1 x C2
C1 C2
+
----------------------



---------------------------------------------------------
=
FP2
1
2
 x R
3 x C3
------------------------------------
=
100
80
60
40
20
0
-20
-40
-60
FP1
FZ2
10M
1M
100K
10K
1K
100
10
OPEN LOOP
ERROR AMP GAIN
FZ1
FP2
20LOG
FLC
FESR
COMPENSATION
FREQUENCY (Hz)
GAIN
20LOG
(VIN/VOSC)
MODULATOR
GAIN
(R2/R1)
FIGURE 6. ASYMPTOTIC BODE PLOT OF CONVERTER GAIN
CLOSED LOOP
GAIN
R4
R1 0.8V
VDDQ 0.8V
-----------------------------------
=


Similar Part No. - ISL6532CR

ManufacturerPart #DatasheetDescription
logo
Intersil Corporation
ISL6532CR INTERSIL-ISL6532CR Datasheet
365Kb / 14P
   ACPI Regulator/Controller for Dual Channel DDR Memory Systems
ISL6532CR-T INTERSIL-ISL6532CR-T Datasheet
365Kb / 14P
   ACPI Regulator/Controller for Dual Channel DDR Memory Systems
ISL6532CRZ INTERSIL-ISL6532CRZ Datasheet
365Kb / 14P
   ACPI Regulator/Controller for Dual Channel DDR Memory Systems
ISL6532CRZ-T INTERSIL-ISL6532CRZ-T Datasheet
365Kb / 14P
   ACPI Regulator/Controller for Dual Channel DDR Memory Systems
More results

Similar Description - ISL6532CR

ManufacturerPart #DatasheetDescription
logo
Intersil Corporation
ISL6532C INTERSIL-ISL6532C Datasheet
506Kb / 16P
   ACPI Regulator/Controller for Dual Channel DDR Memory Systems
logo
Renesas Technology Corp
ISL6532A RENESAS-ISL6532A Datasheet
890Kb / 18P
   ACPI Regulator/Controller for Dual Channel DDR Memory Systems
logo
Intersil Corporation
ISL6537ACRZ-T INTERSIL-ISL6537ACRZ-T Datasheet
413Kb / 16P
   ACPI Regulator/Controller for Dual Channel DDR Memory Systems
ISL6548 INTERSIL-ISL6548 Datasheet
464Kb / 15P
   ACPI Regulator/Controller for Dual Channel DDR Memory Systems
logo
Richtek Technology Corp...
RT9644 RICHTEK-RT9644 Datasheet
357Kb / 17P
   ACPI Regulator/Controller for Dual Channel DDR Memory Systems
logo
Intersil Corporation
ISL6548A INTERSIL-ISL6548A_06 Datasheet
500Kb / 16P
   ACPI Regulator/Controller for Dual Channel DDR Memory Systems
logo
Renesas Technology Corp
ISL6548A RENESAS-ISL6548A Datasheet
788Kb / 16P
   ACPI Regulator/Controller for Dual Channel DDR Memory Systems
logo
Intersil Corporation
ISL6548A INTERSIL-ISL6548A Datasheet
494Kb / 16P
   ACPI Regulator/Controller for Dual Channel DDR Memory Systems
ISL6548 INTERSIL-ISL6548_06 Datasheet
473Kb / 15P
   ACPI Regulator/Controller for Dual Channel DDR Memory Systems
ISL6532 INTERSIL-ISL6532 Datasheet
365Kb / 14P
   ACPI Regulator/Controller for Dual Channel DDR Memory Systems
More results


Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15


Datasheet Download

Go To PDF Page


Link URL




Privacy Policy
ALLDATASHEET.NET
Does ALLDATASHEET help your business so far?  [ DONATE ] 

About Alldatasheet   |   Advertisement   |   Contact us   |   Privacy Policy   |   Link Exchange   |   Manufacturer List
All Rights Reserved©Alldatasheet.com


Mirror Sites
English : Alldatasheet.com  |   English : Alldatasheet.net  |   Chinese : Alldatasheetcn.com  |   German : Alldatasheetde.com  |   Japanese : Alldatasheet.jp
Russian : Alldatasheetru.com  |   Korean : Alldatasheet.co.kr  |   Spanish : Alldatasheet.es  |   French : Alldatasheet.fr  |   Italian : Alldatasheetit.com
Portuguese : Alldatasheetpt.com  |   Polish : Alldatasheet.pl  |   Vietnamese : Alldatasheet.vn
Indian : Alldatasheet.in  |   Mexican : Alldatasheet.com.mx  |   British : Alldatasheet.co.uk  |   New Zealand : Alldatasheet.co.nz
Family Site : ic2ic.com  |   icmetro.com