ltc1622 Linear Technology Corporation, ltc1622 Datasheet - Page 3

• Manufacturer Part Number: ltc1622
• Description: Low Input Voltage Current Mode Step-down Dc/dc Controller
• Manufacturer: Linear Technology Corporation

temperature range, otherwise specifications are at T
SYMBOL
PDRV t
PDRV t
TYPICAL PERFORMANCE CHARACTERISTICS
ELECTRICAL CHARACTERISTICS
Note 1: Absolute Maximum Ratings are those values beyond which the life
of a device may be impaired.
Note 2: T
dissipation P
–10.0
V
–2.5
–5.0
–7.5
10.0
SENSE(MAX)
LTC1622CS8; T
LTC1622CMS8; T
7.5
5.0
2.5
45
40
35
30
25
20
15
10
0
5
0
–55 –35
Shutdown Current
vs Supply Voltage
2
r
f
Normalized Oscillator Frequency
vs Temperature
V
IN
J
is calculated from the ambient temperature T
= 4.2V
3
D
–15
according to the following formula:
4
PARAMETER
Gate Drive Rise Time
Gate Drive Fall Time
Maximum Current Sense Voltage
SUPPLY VOLTAGE (V)
TEMPERATURE ( C)
J
5
= T
J
5
= T
25 45
A
+ (P
A
6
+ (P
D
7
• 150 C/W),
D
65
• 250 C/W)
W
8
85 105
9
1622 G04
1622 G01
U
125
10
0.810
0.805
0.800
0.795
0.790
0.785
0.780
0.775
A
3.50
3.00
2.50
2.00
1.50
1.00
and power
–55 –35
2
A
RUN/SS Current vs Supply Voltage
Reference Voltage
vs Temperature
V
= 25 C. V
IN
CONDITIONS
C
C
3
= 4.2V
LOAD
LOAD
The
–15
4
= 3000pF
= 3000pF
SUPPLY VOLTAGE (V)
TEMPERATURE ( C)
IN
5
denotes specifications which apply over the full operating
5
= 4.2V
25 45
6
Note 3: The LTC1622 is tested in a feedback loop that servos V
feedback point for the error amplifier (V
Note 4: Dynamic supply current is higher due to the gate charge being
delivered at the switching frequency.
7
65
8
85 105
9
1622 G02
1622 G05
125
10
2.10
2.05
2.00
1.95
1.90
1.85
1.80
1.75
110
100
90
80
70
60
50
40
30
–55 –35
20
Maximum Current Sense Voltage
vs Duty Cycle
Undervoltage Lockout Voltage
vs Temperature
V
MIN
IN
80
30
= 4.2V
ITH
–15
= 0.8V).
40
TEMPERATURE ( C)
TYP
100
110
DUTY CYCLE (%)
5
80
50
25 45
60
LTC1622
MAX
140
140
140
70
UNSYNC
65
80
FB
85 105
to the
90
UNITS
1622 G03
1622 G06
3
mV
100
125
ns
ns