LT1612_15 Datasheet, PDF (3/12 Pages) Linear Technology – Synchronous, Step-Down 800kHz PWM DC/DC Converter

LT1612
ELECTRICAL CHARACTERISTICS The q denotes specifications which apply over the full operating
temperature range, otherwise specifications are TA = 25°C, VIN = VSHDN = 3V
SYMBOL PARAMETER
SHDN Pin Current
BOOST Pin Current
Switch Current Limit (Note 4)
CONDITIONS
SHDN = 2V
SHDN = 5V
BOOST = V_IN + 2V
Duty Cycle = 0%
MODE = OV
MIN
q
q
600
TYP MAX
10
15
30
45
4
710 900
UNITS
µA
µA
mA
mA
MODE = 5V
550 650 900
mA
Burst Mode Operation Current Limit
MODE = 0V
180
mA
Switch Voltage Drop
Rectifier Voltage Drop
SW Pin Leakage
I_SW = 500mA
I_RECT = 500mA
V_SW = 5V, V_SHDN = 0V
200 280
mV
300 400
mV
q
1
µA
Note 1: Absolute Maximum Ratings are those values beyond which the life
of a device may be impaired.
Note 2: The LT1612E is guaranteed to meet performance specifications
from 0°C to 70°C. Specifications over the –40°C to 85°C operating
temperature range are assured by design, characterization and correlation
with statistical process controls.
Note 3: Bias current flows out of the FB pin.
Note 4: Duty cycle affects current limit due to slope compensation.
TYPICAL PERFOR A CE CHARACTERISTICS
FB Voltage vs Temperature
0.64
0.63
0.62
0.61
0.60
0.59
– 50 –25 0
25 50
TEMPERATURE (°C)
75 100
1612 • G01
Quiescent Current vs Temperature
190
MODE = 0V
180
170
160
150
140
130
120
110
100
– 50 –25 0 25 50 75 100
TEMPERATURE (°C)
1612 • G02
FB Pin Bias Current
0
–2
–4
–6
–8
–10
–12
–14
–16
–18
–20
– 50 – 25 0
25 50
TEMPERATURE (°C)
75 100
1612 • G03
sn1612 1612fs
3