Datasheet

2
LTC660
ABSOLUTE MAXIMUM RATINGS
W
WW
U
PACKAGE/ORDER INFORMATION
W
U
U
Supply Voltage (V
+
).................................................. 6V
Input Voltage on Pins 1, 6, 7
(Note 2) ............................ –0.3V < V
IN
< (V
+
+ 0.3V)
Output Short-Circuit Duration to GND
(Note 5) ............................................................. 1 sec
Power Dissipation.............................................. 500mW
Operating Temperature Range .................... 0°C to 70°C
Storage Temperature Range ................. –65°C to 150°C
Lead Temperature (Soldering, 10 sec).................. 300°C
(Note 1)
1
2
3
4
8
7
6
5

TOP VIEW
BOOST
CAP
+

GND
CAP
–
V
+

OSC
LV
V
OUT


N8 PACKAGE
8-LEAD PLASTIC DIP
S8 PACKAGE
8-LEAD PLASTIC SOIC
660
T
JMAX
= 100°C, θ
JA
= 100°C/W (N)
T
JMAX
= 100°C, θ
JA
= 150°C/W (S)
Consult Factory for Industrial and Military grade parts.
LTC660CN8
LTC660CS8
ORDER PART
NUMBER
S8 PART MARKING
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
Supply Voltage R
L
= 1k Inverter, LV = Open ● 3 5.5 V
Inverter, LV = GND
● 1.5 5.5 V
Doubler, LV = V
OUT
● 2.5 5.5 V
I
S
Supply Current No Load Boost = Open ● 0.08 0.5 mA
Boost = V
+
● 0.23 3 mA
I
OUT
Output Current V
OUT
More Negative Than –4V ● 100 mA
R
OUT
Output Resistance I
L
= 100mA (Note 3) ● 6.5 10 Ω
f
OSC
Oscillator Frequency Boost = Open 10 kHz
Boost = V
+
(Note 4) 80 kHz
Power Efficiency R
L
= 1k Connected Between V
+
and V
OUT
● 96 98 %
R
L
= 500Ω Connected Between V
OUT
and GND ● 92 96 %
I
L
= 100mA to GND 88 %
Voltage Conversion Efficiency No Load 99 99.96 %
Oscillator Sink or Source Current Boost = Open ±1.1 µA
Boost = V
+
±5.0 µA
V
+
= 5V, C1 and C2 = 150µF, Boost = Open, C
OSC
= 0pF, T
A
= 25°C, unless otherwise noted.
ELECTRICAL CHARACTERISTICS
The ● denotes specifications which apply over the full operating
temperature range; all other limits and typicals are at T
A
= 25°C.
Note 1: Absolute Maximum Ratings are those values beyond which the life
of a device may be impaired.
Note 2: Connecting any input terminal to voltages greater than V
+
or less
than ground may cause destructive latch-up. It is recommended that no
inputs from source operating from external supplies be applied prior to
power-up of the LTC660.
Note 3: The output resistance is a combination of internal switch
resistance and external capacitor ESR. To maximize output voltage and
efficiency, keep external capacitor ESR < 0.2Ω.
Note 4: f
OSC
is tested with C
OSC
= 100pF to minimize the effects of test
fixture capacitance loading. The 0pF frequency is correlated to this 100pF
test point, and is intended to simulate the capacitance at Pin 7 when the
device is plugged into a test socket and no external capacitor is used.
Note 5: OUT may be shorted to GND for 1 sec without damage, but
shorting OUT to V
+
may damage the device and should be avoided. Also,
for temperatures above 85°C, OUT must not be shorted to GND or V
+
,
even instantaneously, or device damage may result.