Datasheet

Data Sheet ADP1621
Rev. B | Page 9 of 32
45
0
0 1800
SWITCHING FREQUENCY (kHz)
PIN SUPPLY CURRENT (mA)
MOSFET Q
G
= 25nC
MOSFET Q
G
= 15nC
MOSFET Q
G
= 7nC
40
35
30
25
20
15
10
5
200 400 600 800 1000 1200 1400 1600
06090-010
Figure 11. PIN Supply Current vs. Switching Frequency
2.60
2.40
–50 150
TEMPERATURE (°C)
V
UVLO
(V)
SDSN = 5V
2.55
2.50
2.45
0 50 100
06090-011
Figure 12. V
UVLO
Threshold vs. Temperature
1.03
0.97
–50 150
TEMPERATURE (°C)
NORMALIZED FREQUENCY (f
OSC
/f
OSC,25°C
)
0 50 100
1.02
1.01
1.00
0.99
0.98
V
IN
= 5V
06090-012
Figure 13. Frequency vs. Temperature
35
0
0 50
GATE CAPACITANCE (nF)
GATE RISE AND FALL TIMES (ns)
30
25
20
15
10
5
5 10 15
20 25 30 35 40 45
T
A
= 25°C
V
IN
= V
PIN
= 5V
t
R
OR
t
F
IS FROM
10% TO 90% OF
THE GATE VOLTAGE
t
F
t
R
06090-013
Figure 14. GATE Rise and Fall Times vs. C
GATE
1600
0
0 200
R
FREQ
(kΩ)
f
OSC
(kHz)
1500
1400
1300
1200
1100
1000
900
800
700
600
500
400
300
200
100
20 40 60 80 100 120 140 160 180
06090-014
Figure 15. Oscillator Frequency vs. Resistance
198
191
2
V
IN
(V)
f
OSC
(kHz)
197
196
195
194
193
192
3 4 5
T
A
= 25°C
R
FREQ
= 100kΩ
06090-015
Figure 16. Oscillator Frequency vs. V
IN