Datasheet

3
LTC1144
TYPICAL PERFORMANCE CHARACTERISTICS
U
W
SUPPLY VOLTAGE (V)
2
OSCILLATOR FREQUENCY (kHz)
10
100
1000
610144 8 12 16 18
LTC1144 • TPC03
1
T
A
= 25°C
C
OSC
= 0
BOOST = V
+
BOOST = OPEN OR GROUND
Oscillator Frequency
vs Supply Voltage
Output Resistance
vs Supply Voltage
SUPPLY VOLTAGE (V)
2
0
OUTPUT RESISTANCE (Ω)
50
100
150
200
6101418
LTC1144 • TPC01
250
300
4 8 12 16
T
A
= 25°C
TEMPERATURE (°C)
–55
OUTPUT RESISTANCE (Ω)
100
120
140
25 75
LTC1144 • TPC02
80
60
–25 0
50 100 125
40
20
V
+
= 5V
I
L
= 3mA
V
+
= 15V
I
L
= 20mA
Output Resistance vs Temperature
Oscillator Frequency
vs Temperature
Output Voltage vs Load Current
Oscillator Frequency as a
Function of C
OSC
EXTERNAL CAPACITANCE (PIN 7 TO GND), C
OSC
(pF)
1
OSCILLATOR FREQUENCY (kHz)
1
10
10000
LTC1144 • TPC04
0.1
0.01
10
100
1000
1000
100
T
A
= 25°C
V
+
= 15V
BOOST = OPEN OR GROUND
BOOST = V
+
LOAD CURRENT (mA)
0
–15
OUTPUT VOLTAGE (V)
–10
–5
0
10 20 30 40
LTC1144 • TPC06
50
60
T
A
= 25°C
V
+
= 15V
C1 = C2 = 10µF
BOOST = OPEN
R
OUT
= 56Ω

TEMPERATURE (°C)
–55 –25
OSCILLATOR FREQUENCY (kHz)
10
100
1000
0 25 50 75 100 125
LTC1144 • TPC05
1
BOOST = V
+
BOOST = OPEN OR GROUND
T
A
= 25°C
V
+
= 15V
Power Conversion Efficiency and
Supply Current vs Load Current
LOAD CURRENT (mA)
0
–5
OUTPUT VOLTAGE (V)
–4
–3
–2
–1
0
5
10 15 20
LTC1144 • TPC07
25 30
T
A
= 25°C
V
+
= 5V
C1 = C2 = 10µF
BOOST = OPEN
R
OUT
= 90Ω
Output Voltage vs Load Current
Supply Current as a Function of
Oscillator Frequency
OSCILLATOR FREQUENCY (kHz)
0.01
SUPPLY CURRENT (µA)
100
1000
100
LTC1144 • TPC08
10
1
0.1
1
10
10000
T
A
= 25°C
C1 = C2 = 10µF
V
+
= 15V
V
+
= 5V
LOAD CURRENT (mA)
0
POWER CONVERSION EFFICIENCY (%)
SUPPLY CURRENT (mA)
60
80
100
40
LTC1144 • TPC09
40
20
0
60
80
100
40
20
0
10
20
30
50
P
EFF
I
S
T
A
= 25°C
V
+
= 15V
C1 = C2 = 10µF
BOOST = OPEN
(SEE TEST CIRCUIT)