LX1734
TM
®
1.0MHz Inverting DC/DC Converter
ABSOLUTE MAXIMUM RATINGS
PACKAGE PIN OUT
Supply Voltage (V
IN
), Shutdown (
SD
).................................................... 0 to 10V
SW Voltage....................................................................................... -0.4V to 20V
NFB Voltage .................................................................................................... -2V
Current Into NFB Pin................................................................................... ±1mA
Operating Temperature Range ............................................................0°C to 85°C
Maximum Junction Temperature ................................................................. 125°C
Storage Temperature......................................................................-65°C to 150°C
Peak Package Solder Reflow Temperature
(40 second maximum exposure) ..................................................... 260°C (+0, -5)
Note: Exceeding these ratings could cause damage to the device. All voltages are with respect to
Ground. Currents are positive into, negative out of specified terminal
.
WWW .
Microsemi
.C
OM
SW
GND
NFB
**
V
IN
N/C*
SD
LM P
ACKAGE
(Top View)
* Not Internally Connected.
** Package heatsink should
be connected to ground or
left floating.
RoHS / Pb-free 100% Matte Tin Lead Finish
THERMAL DATA
LM
Plastic LM 6-Pin
THERMAL RESISTANCE
-
JUNCTION TO
A
MBIENT
,
θ
JC
8°C/W
Junction Temperature Calculation: T
J
= T
A
+ (P
D
x
θ
JC
).
The
θ
JC
numbers are guidelines for the thermal performance of the device/pc-board
system. All of the above assume no ambient airflow.
FUNCTIONAL PIN DESCRIPTION
N
AME
SW
GND
Power Switch Pin
D
ESCRIPTION
Common ground reference
Feedback Pin - Connect to a resistive divider in order to set the output voltage. Feedback threshold is -1.235V.
Given the typical NFB bias current (I
NFB
) of 4µA flows out of the pin, the suggested value for R2 is 10K. Given
R
2
, set R
1
according to:
NFB
R
1
=
VOUT
1 . 235
R
2
−
1 . 235
+
I NFB
(
)
V
IN
Input Supply – Input pin must be locally bypassed.
Shutdown, Connected to >2V, device is active.
SD
P
ACKAGE
D
ATA
P
ACKAGE
D
ATA
Copyright
©
2002
Rev. 3.0a, 2005-03-14
Microsemi
Microsemi Integrated Products
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 2
MICROSEMI [ MICROSEMI CORPORATION ]
