MAX1956ETI Maxim Integrated Products, MAX1956ETI Datasheet - Page 10

• Manufacturer Part Number: MAX1956ETI
• Description: DC/DC Switching Controllers
• Manufacturer: Maxim Integrated Products

Specifications of MAX1956ETI

• Number Of Outputs: 2
• Output Voltage: 0.8 V to 4.95 V
• Input Voltage: 1.6 V to 5.5 V
• Package / Case: TQFN EP-28
• Maximum Operating Temperature: + 85 C
• Minimum Operating Temperature: - 40 C
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

The MAX1955/MAX1956 are dual-output, fixed-frequency,
voltage-mode, PWM step-down controllers with 0.5%
output accuracy. Each controller switches at a constant
600kHz and is 180° out-of-phase with the other con-
troller, which reduces input ripple current and the num-
ber of input capacitors. Figure 1 is the functional
diagram.
1.6V to 5.5V Input, 0.5% Accurate, Dual
180° Out-of-Phase Step-Down Controllers
Figure 1. Functional Diagram
10
______________________________________________________________________________________
(2 x f
COMP1
COMP2
GND1
SYNC
GND
SEQ
FB1
FB2
SW
EN
)
CURRENT LIMIT
SHUTDOWN
AND
Detailed Description
SEQUENCING
OSCILLATOR
MARGINING
SHUTDOWN
START DAC
VOLTAGE
SOFT-
AND
1.28V
REF
EA
f
f
SW
SW
CONVERTER 2
BIAS
AVDD
PWM
An on-chip step-up bias supply generates a 5V gate
drive to deliver up to 25A output current per phase with
low-cost N-channel MOSFETs at up to 93% efficiency.
Lossless adjustable current limit eliminates expensive
current-sense resistors and improves efficiency.
Foldback current limit reduces power dissipation during
short-circuit condition and handles transient overloads
better than controllers using hiccup-mode short-circuit
protection.
CONVERTER 1
IN
UVLO
R
S
CONTROL
BOOST
x0.15
Q
Q
1V
5µA
4V
VDD2
LXB
PGND
BST1
DH1
LX1
VDD1
DL1
PGND1
ILIM1
BST2
DH2
LX2
VDD2
DL2
PGND2
ILIM2