MAX17582GTM+ Maxim Integrated Products, MAX17582GTM+ Datasheet - Page 22

• Manufacturer Part Number: MAX17582GTM+
• Description: IC PWM CTRLR STP-DN DL 48TQFN
• Manufacturer: Maxim Integrated Products
• Series: Quick-PWM™r

Specifications of MAX17582GTM+

• Applications: Controller, Intel IMVP-6.5™
• Voltage - Input: 4.5 ~ 5.5 V
• Number Of Outputs: 1
• Voltage - Output: 0.01 ~ 1.5 V
• Operating Temperature: -40°C ~ 105°C
• Mounting Type: Surface Mount
• Package / Case: 48-TQFN Exposed Pad
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Dual-Phase, Quick-PWM Controller for
IMVP-6.5 CPU Core Power Supplies
Use the worst-case inductance and R
vided by the inductor manufacturer, adding some mar-
gin for the inductance drop over temperature and load.
To minimize the current-sense error due to the current-
sense inputs’ bias current (I
R1||R2 to be less than 2kΩ and use the previous equa-
tion to determine the sense capacitance (C
capacitors with 5% tolerance and resistors with 1% tol-
erance specifications. Temperature compensation is
recommended for this current-sense method. See the
Voltage Positioning and Loop Compensation section for
detailed information.
When using a current-sense resistor for accurate output-
voltage positioning, the circuit requires a differential RC
filter to eliminate the AC voltage step caused by the
equivalent series inductance (L
Figure 3. Current-Sense Methods
22
______________________________________________________________________________________
A) OUTPUT SERIES RESISTOR SENSING
B) LOSSLESS INDUCTOR SENSING
MAX17582
MAX17582
CSP
PGND
PGND
CSN_
CSN_
CSP_
CSP_
DH_
DH_
DL_
DL_
LX_
LX_
ESL
_ and I
) of the current-sense
N
N
N
N
DCR
H
H
L
L
CSN
EQ
values pro-
_), choose
). Choose
D
C
D
C
L
IN
L
IN
L
R1
L
INDUCTOR
INPUT (V
INPUT (V
resistor (see Figure 3). The ESL induced-voltage step
does not affect the average current-sense voltage, but
results in a significant peak current-sense voltage error
that results in unwanted offsets in the regulation voltage
and results in early current-limit detection. Similar to the
inductor DCR sensing method above, the RC filter’s time
constant should match the L/R time constant formed by
the current-sense resistor’s parasitic inductance:
where L
current-sense resistor, R
tance value, and C
matching components.
FOR THERMAL COMPENSATION:
R2 SHOULD CONSIST OF AN NTC RESISTOR IN
SERIES WITH A STANDARD THIN-FILM RESISTOR.
L
SENSE RESISTOR
ESL
R1
R
DCR
C
R2
EQ
IN
IN
)
)
R
ESL
SENSE
C
EQ
is the equivalent series inductance of the
C
OUT
EQ
C
R
OUT
R
L
R
DCR
SENSE
CS
and R1 are the time-constant
ESL
SENSE
=
=
(
C
C
L
EQ
EQ
R1 + R2
[
R1 =
R2
=
R1 R2
1
C
is current-sense resis-
+
L
R
EQ
)
SENSE
SENSE
1
R
]
DCR
R
1