Datasheet

LTC3261
3
3261fb
For more information www.linear.com/3261
elecTrical characTerisTics
The l denotes the specifications which apply over the specified operating
junction temperature range, otherwise specifications are at T
A
= 25°C (Note 2). V
IN
= EN = 12V, MODE = 0V, RT = 200kΩ.
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
Charge Pump
V
IN
Input Voltage Range
l
4.5 32 V
V
UVLO
V
IN
Undervoltage Lockout Threshold V
IN
Rising
V
IN
Falling
l
l
3.4
3.8
3.6
4 V
V
I
VIN
V
IN
Quiescent Current Shutdown, = EN = 0V
MODE = V
IN
, I
VOUT
= 0mA
MODE = 0V, I
VOUT
= 0mA
2
60
3.5
5
120
5.5
µA
µA
mA
V
RT
RT Regulation Voltage 1.200 V
V
OUT
V
OUT
Regulation Voltage MODE = 12V
MODE = 0V
–0.94 • V
IN
–V
IN
V
V
f
OSC
Oscillator Frequency RT = GND 450 500 550 KHz
R
OUT
Charge Pump Output Impedance MODE = 0V, RT = GND 32 Ω
I
SHORT_CKT
Max I
VOUT
Short-Circuit Current V
OUT
= GND, RT = GND
l
100 160 250 mA
V
MODE(H)
MODE Threshold Rising
l
1.1 2 V
V
MODE(L)
MODE Threshold Falling
l
0.4 1.0 V
I
MODE
MODE Pin Internal Pull-Down Current V
IN
= MODE = 32V 0.7 µA
V
EN(H)
EN Threshold Rising
l
1.1 2 V
V
EN(L)
EN Threshold Falling
l
0.4 1.0 V
I
EN
EN Pin Internal Pull-Down Current V
IN
= EN = 32V 0.7 µA
Note 1: Stresses beyond those listed under Absolute Maximum Ratings
may cause permanent damage to the device. Exposure to any Absolute
Maximum Rating condition for extended periods may affect device
reliability and lifetime.
Note 2: The LTC3261 is tested under pulsed load conditions such that
T
J
≈ T
A
. The LTC3261E is guaranteed to meet specifications from
0°C to 85°C junction temperature. Specifications over the –40°C to
125°C operating junction temperature range are assured by design,
characterization and correlation with statistical process controls. The
LTC3261I is guaranteed over the –40°C to 125°C operating junction
temperature range, the LTC3261H is guaranteed over the –40°C to 150°C
operating junction temperature range and the LTC3261MP is tested and
guaranteed over the full –55°C to 150°C operating junction temperature
range. High junction temperatures degrade operating lifetimes; operating
lifetime is derated for junction temperatures greater than 125°C. Note that
the maximum ambient temperature consistent with these specifications
is determined by specific operating conditions in conjunction with board
layout, the rated package thermal impedance and other environmental
factors.
The junction temperature (T
J
, in °C) is calculated from the ambient
temperature (T
A
, in °C) and power dissipation (P
D
, in Watts) according to
the formula:
T
J
= T
A
+ (P
D
• θ
JA
),
where θ
JA
= 40°C/W is the package thermal impedance.
Note 3: This IC includes overtemperature protection that is intended
to protect the device during momentary overload conditions. Junction
temperatures will exceed 150°C when overtemperature protection is
active. Continuous operation above the specified maximum operating
junction temperature may result in device degradation or failure.