MAX17003ETJ+ Maxim Integrated Products, MAX17003ETJ+ Datasheet - Page 20

• Manufacturer Part Number: MAX17003ETJ+
• Description: IC PS CTRLR FOR NOTEBOOKS 32TQFN
• Manufacturer: Maxim Integrated Products

Specifications of MAX17003ETJ+

• Applications: Controller, Notebook Computers
• Voltage - Input: 6 ~ 26 V
• Number Of Outputs: 4
• Voltage - Output: 3.3V, 5V, 2 ~ 5.5 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 32-TQFN Exposed Pad
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

High-Efficiency, Quad-Output, Main Power-
Supply Controllers for Notebook Computers
20
When the switching regulators are disabled—when ON_
or SHDN is pulled low, or when an output undervoltage
fault occurs—the internal soft-discharge gradually
decreases the output voltage by pulling DSCHG_ low
(see the SMPS Shutdown Waveform in the Typical
Operating Characteristics ). This slowly discharges the
output capacitance, eliminating the negative output volt-
ages caused by quickly discharging the output through
the inductor and low-side MOSFET. Both SMPS con-
trollers contain separate soft-shutdown circuits.
Figure 3. PWM Controller Functional Diagram
______________________________________________________________________________________
CSH_
CSL_
DRVA
OUTA
SKIP
ILIM
Output Discharge (Soft-Discharge)
TRI-LEVEL
DECODE
A = 1.2
A = 1/10
0.2 x V LIMIT
ONE-SHOT
PEAK CURRENT
NEG CURRENT
PGND
CROSSING
5V SMPS ONLY
IDLE MODE
CURRENT
LIMIT
LIMIT
ZERO
0.1 x V
LIMIT
GND
The heart of each current-mode PWM controller is a
multi-input, open-loop comparator that sums two sig-
nals: the output-voltage error signal with respect to the
reference voltage and the slope-compensation ramp
(Figure 3). The MAX17003/MAX17004 use a direct-
summing configuration, approaching ideal cycle-to-
cycle control over the output voltage without a
traditional error amplifier and the phase shift associated
with it.
SLOPE COMP
S
R
Q
R
S
Q
Fixed-Frequency, Current-Mode
START/STOP
SOFT-
OSC
DL DRIVER
DH DRIVER
(SEE FIGURE 5)
FROM FB
PWM Controller
FSEL
ON_
REF