MAX1956ETI Maxim Integrated Products, MAX1956ETI Datasheet - Page 21

• 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

Careful PC board layout is important in any switching
regulator. The switching power stage requires particular
attention. Follow these guidelines for good PC board
layout:
1) Place decoupling capacitors as close as possible to
2) Keep a separate power ground plane (connect to
3) Connect the drains of the MOSFETs to a large land
4) Ensure all feedback connections are short and
5) Route high-speed switching nodes (LX_) away from
For a sample PC board layout, refer to the MAX1955
evaluation kit. Table 2 lists typical application circuit
components.
Table 2. Typical Application Circuit
Components
DESIGNATION
N1, N2, N5, N6
N3, N4, N7, N8
the IC pins.
the sources of the low-side MOSFETs, the input and
output capacitors, and PGND_ pins). Connect the
input decoupling capacitors across the drain of the
high-side MOSFETs and the source of the low-side
MOSFETs. The signal ground plane (connected to
the GND pin) is connected to the power ground
plane at a single point. Keep the high-current paths
as short as possible.
area to help cooling the devices to further improve
efficiency and long-term reliability.
direct. Place the feedback resistors as close to the
IC as possible.
sensitive analog areas (FB_, COMP_).
C10–C13
C28, C29
D1–D4
L1, L2
L3
Applications Information
______________________________________________________________________________________
QTY
PC Board Layout Guidelines
4
2
4
2
1
4
4
180° Out-of-Phase Step-Down Controllers
1.6V to 5.5V Input, 0.5% Accurate, Dual
680µF, 2.5V POSCAPs
Sanyo 2R5TPD680M8
470µF, 6.3V POSCAPs
Sanyo 6TPB470M
Schottky diodes (SOT 323)
Central CMSSH-3
0.3µH, 35A inductors
Sumida CDEP125(U)-0R3
4.7µH inductor
TDK LDR655312T-4R7W
N-channel MOSFETs
Vishay Si7892DP
N-channel MOSFETs
Vishay Si4842DY
DESCRIPTION
TRANSISTOR COUNT: 8694
PROCESS: BiCMOS
TOP VIEW
SYNC
ILIM1
BST1
DH1
DL1
LX1
EN
1
2
3
4
5
6
7
THIN QFN
MAX1955
MAX1956
Pin Configuration
Chip Information
21
20
19
18
17
16
15
DL2
LX2
DH2
BST2
SEQ
AV
ILIM2
DD
21