MAX1956ETI-T Maxim Integrated Products, MAX1956ETI-T Datasheet - Page 9

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

Specifications of MAX1956ETI-T

• 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

Exposed
PIN
Pad
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
6
7
8
9
COMP1
COMP2
PGND2
PGND1
NAME
GND1
PGND
ILIM1
ILIM2
AV
BST2
V
V
GND
SEQ
DH2
FB1
REF
FB2
LX2
DL2
LXB
EN
DD2
DD1
IN
—
DD
_______________________________________________________________________________________
Enable and Voltage Margining Input. Connect EN to IN for normal operation or connect to GND for shutdown.
Set V
nominal (see the Shutdown and Output Voltage Margining (EN) section).
Current-Limit Adjust. Sets the threshold for current sensing across the low-side MOSFET’s R
ILIM1 to AV
the Current Limit section.
Feedback Input. Connect to a voltage-divider from the output to GND to set the output voltage (see the
Setting the Output Voltage section).
C om p ensati on. Inter nal l y p ul l ed to g r ound d ur i ng shutd ow n ( see the C om p ensati on D esi g n secti on) .
Ground. Connect to the PC board analog ground plane. Connect PC board power ground plane and analog
ground plane with a single connection.
1.28V Reference. Connect a 0.22µF capacitor from REF to GND.
Ground. Connect to the PC board analog ground plane. Connect the PC board power ground plane and
analog ground plane with a single connection.
C om p ensati on. Inter nal l y p ul l ed to g r ound d ur i ng shutd ow n ( see the C om p ensati on D esi g n secti on) .
Feedback Input. Connect to a voltage-divider from the output to GND to set the output voltage (see the
Setting the Output Voltage section).
Current-Limit Adjust. Sets the threshold for current sensing across the low-side MOSFET’s R
ILIM2 to AVDD for a 150mV threshold. For adjustable constant current or foldback current-limit setting, see
the Current Limit section.
Analog Supply Input. Connect a 10Ω resistor from V
Power-Sequence Input. Connect SEQ to GND to set OUT1 and OUT2 to power up and power down
simultaneously. Connect SEQ to IN to make OUT1 power up first and power down last.
High-Side MOSFET Gate-Driver Bootstrap Connection. Connect a capacitor from BST2 to LX2 and a Schottky
diode from V
High-Side MOSFET Gate-Driver Output. Connect to the high-side MOSFET gate. DH2 is pulled low in
shutdown.
Inductor Connection. Connect to the switched side of the inductor.
Low-Side MOSFET Gate-Driver Output. Connect to the low-side MOSFET gate. DL2 is pulled low in shutdown.
Power Ground. Connect to the low-side MOSFET source for regulator 2 and PC board power ground plane.
Input Supply
Internal Boost Regulator Output. Connect to V
Internal Boost Regulator Inductor Connection. Connect a 4.7µH inductor from LXB to IN. Internally shorted to
V
Power Ground. Connect to PC board power ground plane.
Internal Boost Regulator Output. Connect to V
Power Ground. Connect to the low-side MOSFET source for regulator 1 and PC board power ground plane.
Exposed Pad. Solder to the PC board analog ground plane for optimum power dissipation.
180° Out-of-Phase Step-Down Controllers
DD2
1.6V to 5.5V Input, 0.5% Accurate, Dual
EN
in shutdown.
= (1/3)V
DD
DD
for a 150mV threshold. For adjustable constant current or foldback current-limit setting, see
to BST2.
IN
to set the outputs to -4% of nominal. Set V
DD1
DD2
FUNCTION
, and bypass with a 10µF capacitor to GND.
.
DD
to AV
Pin Description (continued)
DD
EN
= (2/3)V
and a 0.47µF capacitor from AV
IN
to set the outputs to +4% of
DS(ON)
DS(ON)
DD
. Connect
. Connect
to GND.
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