si3400 Silicon Laboratories, si3400 Datasheet - Page 10

• Manufacturer Part Number: si3400
• Description: Fully-integrated 802.3-compliant Pd Interface And Switching Regulator
• Manufacturer: Silicon Laboratories

Si3400/Si3401
*Note: This is a simplified schematic. See “AN296:
10
PS2911
TLV431
Item
C1
C2
C3
C4
C5
C7
C8
R1
R2
R3
R4
R5
R6
R7
R8
D1
D2
D3
T1
Designs”
RJ-45
To Ethernet PHY
Voltage reference
Optocoupler
Transformer
for more details and complete application schematics.
Capacitor
Capacitor
Capacitor
Capacitor
Capacitor
Capacitor
Capacitor
Resistor
Resistor
Resistor
Resistor
Resistor
Resistor
Resistor
Resistor
Diode
Diode
Diode
Type
Table 9. Components—Class 1 with Isolated 5.0 V Output
Figure 2. Schematic—Class 1 with Isolated 5.0 V Output*
C2
R1
R8
C1
1100 µF
25.5 kΩ
4.99 kΩ
2.05 kΩ
36.5 kΩ
12.1 kΩ
220 nF
0.1 µF
0.1 µF
100 Ω
10 kΩ
127 Ω
40 µH
Value
15 µF
15 nF
1 µF
10 A
15 V
1 A
CT1
CT2
SP1
SP2
RDET
RCL
Using the Si3400/01 PoE PD Controller in Isolated and Non-Isolated
Preliminary Rev. 0.91
Si3400
Si3401
Toler.
20%
20%
20%
10%
10%
20%
20%
1%
1%
1%
1%
1%
1%
1%
1%
ISOSSFT
EROUT
SWO
VDD
C7
1/16 W
1/16 W
1/16 W
1/16 W
1/16 W
1/16 W
1/16 W
1/16 W
Rating
100 V
100 V
100 V
10 V
16 V
16 V
16 V
16 V
40 V
9 A
D2
D3
C8
R2
C5
R3
T1
Switcher supply capacitor. Several paral-
lel capacitors are used for lower ESR.
PD input supply capacitor.
Switcher load capacitor. 100 µF in paral-
lel 1000 µF and optional 1 µH inductor for
additional filtering.
Feedback compensation.
Feedback compensation.
VDD bypass capacitor.
Isolated mode soft start (tie ISOSSFT to
VDD if this feature is not used).
Detection resistor.
Pull-up resistor.
Feedback compensation resistor.
Feedback compensation resistor.
Pull-up resistor.
Feedback resistor divider.
Feedback resistor divider.
Classification resistor.
Schottky diode; part no. PN PDS1040.
Snubber diode (1N4148)
Snubber diode (DFLT15A)
Coilcraft part number FA2672 (5 V).
PS2911
D1
R5
R4
C4
Notes
R6
R7
C3