SI3500-A-GM Silicon Laboratories Inc, SI3500-A-GM Datasheet - Page 11

• Manufacturer Part Number: SI3500-A-GM
• Description: IC POE SWITCH PWR OVER LAN 20QFN
• Manufacturer: Silicon Laboratories Inc
• Type: Power over Ethernet Switch (PoE)r

Specifications of SI3500-A-GM

• Package / Case: 20-QFN
• Applications: IP Phones, Power over LAN, Network Routers and Switches
• Internal Switch(s): Yes
• Current Limit: 525mA
• Voltage - Supply: 42 V ~ 57 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Minimum Operating Temperature: - 10 C
• Mounting Style: SMD/SMT
• Product: Ethernet Controllers
• Maximum Operating Temperature: + 85 C
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Lead free / RoHS Compliant
• Other names: 336-1844-5

5. Pin Descriptions
9, Pad
Pin#
10
12
13
14
15
11
1
2
3
4
5
6
7
8
ISOSSFT
EROUT
VPOS1
RBIAS
Name
VNEG
VSSA
SSFT
VDD
HSO
NC
NC
NC
NC
NC
NC
Error-amplifier output and PWM input; directly connected to opto-coupler in isolated or
boost applications.
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.
Connect a 0.1 µF capacitor between this pin and VSSA for isolated applications.
Do not connect (float).
A 25.5 k resistor connected from this to VPOS sets up the bias currents of the
Si3500.
Hotswap switch output; connects to VNEG through hotswap switch.
Do not connect (float).
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
Do not connect (float).
Do not connect (float).
High-voltage supply, positive rail (force node)
Do not connect (float).
Do not connect (float).
Analog ground.
Isolated mode soft start enable input. Tie to VDD for non-isolated applications.
Table 8. Si3500 Pin Descriptions (Top View)
ISOSSFT
EROUT
SSFT
VDD
2
heat spreader plane using a minimum of nine thermal vias.
1
2
3
4
20
5
19
6
Rev. 1.1
18
VNEG
(PAD)
7
17
8
16
9
Description
10
15
14
13
12
11
NC
NC
VPOSF
NC
Si3500
11