L5980 STMicroelectronics, L5980 Datasheet - Page 20
L5980
Manufacturer Part Number
L5980
Description
IC REG SW STP DWN 700MA 8-VFQFPN
Manufacturer
STMicroelectronics
Type
Step-Down (Buck)r
Datasheet
1.L5980TR.pdf
(42 pages)
Specifications of L5980
Internal Switch(s)
Yes
Synchronous Rectifier
No
Number Of Outputs
1
Voltage - Output
0.6 ~ 18 V
Current - Output
700mA
Frequency - Switching
250kHz ~ 1MHz
Voltage - Input
2.9 ~ 18 V
Operating Temperature
-40°C ~ 125°C
Mounting Type
Surface Mount
Package / Case
8-VFQFN, 8-VFQFPN
Power - Output
1.5W
Output Voltage
3.3 V
Output Current
0.7 A
Input Voltage
2.9 V to 18 V
Switching Frequency
220 KHz to 275 KHz
Operating Temperature Range
- 40 C to + 150 C
Mounting Style
SMD/SMT
Duty Cycle (max)
100 %
Low Dropout Operation
100% duty cycle
For Use With
497-6384 - BOARD EVAL FOR L5980
Lead Free Status / RoHS Status
Lead free / RoHS Compliant
Available stocks
Company
Part Number
Manufacturer
Quantity
Price
Part Number:
L5980TR
Manufacturer:
ADI/亚德诺
Quantity:
20 000
Application information
20/42
Equation 17
Figure 10. Type III compensation network
In
and the open loop gain (G
Figure 11. Open loop gain: module Bode diagram
The guidelines for positioning the poles and the zeroes and for calculating the component
values can be summarized as follow:
1.
2.
Figure 11
Choose a value for R
Choose a gain (R
the Bode diagram of the PWM and LC filter transfer function (G
f
P0
4
/R
=
0
1
1
LOOP
) in order to have the required bandwidth (BW), that means:
,
, usually between 1 kΩ and 5 kΩ.
Doc ID 13003 Rev 6
f
(f) = G
P1
=
----------------------------- -
2π R
PW0
⋅
1
3
· G
⋅
C
LC
3
,
(f) · G
f
P2
TYPEIII
=
------------------------------------------- -
2π R
⋅
(f)) are drawn.
4
1
⋅
------------------- -
C
C
4
4
+
⋅
C
C
5
5
PW0
· G
LC
L5980
(f))