lx1684 Microsemi Corporation, lx1684 Datasheet - Page 2

• Manufacturer Part Number: lx1684
• Description: Voltage-mode Pwm Controller
• Manufacturer: Microsemi Corporation

Copyright © 2000
Rev. 1.0c, 2005-03-08
P
IN
Supply Voltage (V
Supply Voltage (V
Input Voltage (CSP Pin) ................................................................................. 14V
Output Drive Peak Current Source (500ns) ................................................... 1.0A
Output Drive Peak Current Sink (500ns) ....................................................... 1.0A
Input Voltage (SS/ENABLE Pin) .......................................................... -0.3 to 6V
Operating Junction Temperature.................................................................. 150°C
Storage Temperature ................................................................... -65°C to +150°C
Peak Package Solder Reflow Temp. (40 second max. exposure) ...260°C (+0, -5)
Note:
Junction Temperature Calculation: T
The θ
system. All of the above assume no ambient airflow.
PGND
VCSP
TDRV
BDRV
GND
D
V
V
V
CS
SS
N
THERMAL RESISTANCE
CC
FB
C1
AME
JA
TM
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.
numbers are guidelines for the thermal performance of the device/pc-board
P
A B S O L U T E M A X I M U M R A T I N G S ( N O T E 1 )
ACKAGE
Voltage Feedback. A 1.25V reference is connected to a resistor divider to set desired output voltage.
Soft-Start And Hiccup Capacitor Pin. During start up the voltage of this pin controls the output voltage. An
internal 22kΩ resistor and the external capacitor set the time constant for soft-startup. Soft-start does not begin
until the supply voltage exceeds the UVLO threshold. When over-current occurs, this capacitor is used for timing
hiccup. The PWM can be disabled by pulling the SS pin below 0.3V
Positive Over-Current Threshold Input
Analog ground for SS, FB, CS and VCC.
MOSFET driver power ground
Gate Drive For Upper MOSFET.
Gate Drive For Lower MOSFET.
Separate Supply For MOSFET Gate Drives. Connect to gate drive voltage.
Over-Current Set. Connect resistor between CS pin and the source of the upper MOSFET to set current-limit
point.
IC Supply Voltage (nominal 5V).
C1
CC
) ...................................................................................... 18V
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: [phone]
)........................................................................................ 7V
T H E R M A L D A T A
-
JUNCTION TO AMBIENT
J
= T
F U N C T I O N A L P I N D E S C R I P T I O N
A
+ (P
D
x θ
Integrated Products Division
JA
).
®
Microsemi
, θ
JA
D
ESCRIPTION
Voltage-Mode PWM Controller
165°C/W
P
RODUCTION
RoHS / Pb-free 100% Matte Tin Lead Finish
D
FB
N/C
SS
PGND
BDRV
GND
VCSP
P A C K A G E P I N O U T
ATA
S
HEET
1
2
3
4
5
6
7
14-P
(Top View)
IN
SOIC
14
13
12
11
10
9
8
LX1684
TDRV
N/C
N/C
N/C
V
V
CS
CC
C1
Page 2