XRP7708_12 Datasheet, PDF (7/28 Pages) Exar Corporation – Quad Channel Digital PWM Step Down Controllers

XRP7708 and XRP7740
Quad Channel Digital PWM Step Down Controllers
Name
DGND
AGND
GL1-GL4
GH1-GH4
LX1-LX4
BST1-BST4
GPIO0-GPIO3
GPIO4_SDA,
GPIO5_SCL
VOUT1-VOUT4
LDOOUT
ENABLE
AGND
Pin Number
Description
10
11
35,30,17,22
33,28,19,24
34,29,18,23
32,27,20,25
3,4,5,6
7,8
12,13,14,15
40
9
Exposed Pad
Digital Ground. This pin should be connected to the ground plane at the exposed pad with
a separate trace.
Analog Ground. This pin should be connected to the ground plane at the exposed pad with
a separate trace
Output pin of the low side gate driver. Connect directly to the respective gate of an
external N-channel MOSFET.
Output pin of the high side gate driver. Connect directly to the respective gate of an
external N-channel MOSFET.
Lower supply rail for the high-side gate driver (GHx). Connect this pin to the switching
node at the junction between the two external power MOSFETs and the inductor. These
pins are also used to measure voltage drop across bottom MOSFETs in order to provide
output current information to the control engine.
High side driver supply pin(s). Connect BST to an external boost diode and a capacitor as
shown in the front page diagram.
The high side driver is connected between the BST pin and LX pin.
These pins can be configured as inputs or outputs to implement custom flags, power good
signals and enable/disable controls. A GPIO pin can also be programmed as an input clock
synchronizing IC to external clock. Refer to the “GPIO Pins” Section and the “External
Clock Synchronization” Section for more information.
I²C serial interface communication pins. These pins can be re-programmed to perform
GPIO functions in applications when I²C bus is not used.
Voltage sense.
Connect to the output of the corresponding power stage.
Output of the Standby LDO. It can be configured as a 5V or 3.3V output. A compensation
capacitor should be used on this pin [see Application Note].
If ENABLE is pulled high, the chip powers up (logic reset, registers configuration loaded,
etc.). If pulled low for longer than 100us, the XRP7708/40 is placed into shutdown. See
applications section for proper sequencing of this pin.
Analog Ground. Connect to analog ground (as noted above for pin 11).
ORDERING INFORMATION
Part Number
Junction Temp
Range
Marking
XRP7708ILB- F
-40°C≤TJ≤+125°C
XRP7708ILB
YYWW X
XRP7708ILBTR-F
-40°C≤TJ≤+125°C
XRP7708ILB
YYWW X
XRP7740ILB- F
-40°C≤TJ≤+125°C
XRP7740ILB
YYWW X
XRP7740ILBTR-F
-40°C≤TJ≤+125°C
XRP7740ILB
YYWW X
XRP7740ILB
XRP7740ILB-0X180-F -40°C≤T_J≤+125°C
YYWW X
0X18
XRP7740ILB
XRP7740ILBTR-0X18-F -40°C≤T_J≤+125°C
YYWW X
0X18
XRP7708EVB
XRP7708 Evaluation Board
XRP7740EVB
XRP7740 Evaluation Board
Package
40-pin TQFN
Packing
Quantity
Bulk
40-pin TQFN 3K/Tape & Reel
40-pin TQFN
Bulk
40-pin TQFN 3K/Tape & Reel
40-pin TQFN
Bulk
40-pin TQFN 3K/Tape & Reel
“YY” = Year – “WW” = Work Week – “X” = Lot Number
Note 1
Halogen Free
Halogen Free
Halogen Free
Halogen Free
Halogen Free
Halogen Free
Default I²C
Address
0X18
0X18
© 2012 Exar Corporation
7/28
Rev. 1.2.2