ADP1875 Analog Devices, ADP1875 Datasheet - Page 17

• Manufacturer Part Number: ADP1875
• Description: Synchronous Buck Controller with Constant On-Time, Valley Current Mode, and Power Saving Mode
• Manufacturer: Analog Devices

Figure 59. Upper-Side Driver Rising and Lower-Side Falling Edge Waveforms
Figure 60. Upper-Side Driver Falling and Lower-Side Rising Edge Waveforms
M
M
M
4
3
2
4
3
2
4
3
2
CH3 5V
MATH 2V 40ns
CH3 5V
MATH 2V 40ns
CH3 5V
MATH 2V 20ns
LOW SIDE
HS MINUS
SW
LOW SIDE
T
SW NODE
HS MINUS
SW
A
Figure 58. Output Drivers and SW Node Waveforms
HIGH SIDE
HS MINUS
SW
22ns (
= 25°C
Q
Q
(C
TOTAL
(C
TOTAL
18ns (
t
IN
IN
pdh
= 4.3 nF (Upper-/Lower-Side MOSFET),
= 4.3 nF (Upper-/Lower-Side MOSFET),
= 27 nC (V
= 27 nC (V
DRVH
t
r
,DRVL
CH2 5V
CH4 2V
CH2 5V
CH4 2V
CH2 5V
CH4 2V
)
)
GS
GS
T
= 4.4 V (Q1), V
= 4.4 V (Q1), V
16ns (
11ns (
A
= 25°C
24ns (
M40ns
M40ns
M20ns
T
T
T
t
t
f
f
,DRVL
,DRVH
29.0%
29.0%
39.2%
t
pdh
25ns (
)
)
,DRVL
HIGH SIDE
GS
GS
t
r
= 5 V (Q3))
= 5 V (Q3))
,DRVH
)
HIGH SIDE
SW NODE
A CH2
A CH2
A CH2
LOW SIDE
SW NODE
)
T
A
= 25°C
4.20V
4.20V
4.20V
Rev. 0 | Page 17 of 44
1.30
1.25
1.20
1.15
1.10
1.05
1.00
0.95
0.90
0.85
0.80
0.75
0.70
570
550
530
510
490
470
450
430
680
630
580
530
480
430
380
330
2.7
–40
2.7
Figure 61. Transconductance (G
Figure 62. Transconductance (G
3.0
–20
3.1
Figure 63. Quiescent Current vs. VREG
3.3
0
3.5
3.6
TEMPERATURE (°C)
20
3.9
3.9
VREG (V)
+125°C
VREG (V)
+25°C
–40°C
40
ADP1874/ADP1875
4.2
4.3
m
60
) vs. Temperature
4.5
m
) vs. VREG
4.7
80
4.8
VREG = 5.5V
VREG = 3.6V
VREG = 2.7V
5.1
100
5.1
+125°C
+25°C
–40°C
120
5.4
5.5