SI3402-EVB Silicon Laboratories Inc, SI3402-EVB Datasheet - Page 16

• Manufacturer Part Number: SI3402-EVB
• Description: BOARD EVAL POE FOR SI3402
• Manufacturer: Silicon Laboratories Inc
• Type: PWM Controllersr

Specifications of SI3402-EVB

• Main Purpose: Special Purpose DC/DC, Power Over Ethernet
• Outputs And Type: 1, Non-Isolated
• Voltage - Output: 5V
• Voltage - Input: 44 ~ 57V
• Regulator Topology: Buck
• Frequency - Switching: 350kHz
• Board Type: Fully Populated
• Utilized Ic / Part: Si3402
• Input Voltage: 5 V
• Output Voltage: 3.3 V
• Interface Type: Ethernet
• Maximum Operating Temperature: + 85 C
• Minimum Operating Temperature: - 40 C
• Product: Power Management Modules
• For Use With/related Products: Si3402
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Current - Output: -
• Power - Output: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant
• Other names: 336-1827

Si3402
4. Pin Descriptions
16
9, Pad
Pin#
10
11
12
13
14
15
16
17
18
19
20
1
2
3
4
5
6
7
8
ISOSSFT
EROUT
VPOSS
PLOSS
VPOSF
Name
VNEG
RDET
VSSA
SSFT
VSS1
VSS2
SWO
VDD
HSO
RCL
SP2
SP1
CT2
CT1
FB
Error-amplifier output and PWM input; directly connected to opto-coupler in isolated application.
Soft-start output pin ramps voltage across external soft-start capacitor to allow switcher to ramp
output slowly.
5 V supply rail for switcher; provides drive for opto-coupler.
0.1 µF capacitor between this pin and VSSA for isolated applications.
Early power loss indicator; open drain output is pulled to VPOS when VPORT is applied.
Input pin for external precision detection resistor; also used for establishing absolute current
reference.
Hotswap switch output; connects to VNEG through hotswap switch.
Input pin for external precision classification resistor; float if optional RCLASS is unused.
Rectified high-voltage supply, negative rail. Must be connected to thermal PAD node (VNEG)
on package bottom. This thermal pad must be connected to VNEG (pin #9) as well as a 2 in
heat spreader plane using a minimum of nine thermal vias.
High-voltage supply input from spare pair; polarity-insensitive.
High-voltage supply input from spare pair; polarity-insensitive.
Rectified high-voltage supply, positive rail (force node)
High-voltage supply input from center tap of Ethernet transformer; polarity-insensitive.
High-voltage supply input from center tap of Ethernet transformer; polarity-insensitive.
Analog ground.
Rectified high-voltage supply, positive rail sense node.
Negative supply rail for switcher; externally tied to HSO.
Switching transistor output; drain of switching N-FET.
Negative supply rail for switcher; externally tied to HSO.
Regulated feedback input in non-isolated application.
Isolated mode soft start enable input. Tie to VDD for non-isolated applications. Connect a
Table 12. Si3402 Pin Descriptions (Top View)
ISOSSFT
EROUT
SSFT
VDD
1
2
3
4
20
5
19
6
Rev. 1.2
18
VNEG
(PAD)
7
17
8
16
9
Description
10
15
14
13
12
11
CT2
CT1
VPOSF
SP1
2