Si3482
P OWER M ANAGEMENT C ON TROLLER
Features
Pin Assignments
RX
RSVD
INT
TX
19
NSS
20
MOSI
21
17 SCL
GND
3
VDD
4
RST
5
14 BAUD2
RSVD
6
13 PSLCT
11
12
RSVD
RSVD
PS3
PS2
PS1
Top View
(Pads on Bottom of Package)
10
Industrial automation systems
Networked audio
IP Phone Systems and iPBXs
Metropolitan area networked WAPs,
cameras, and sensors
WiMAX, ASN/BTS, and CPE/ODU
systems
18 SDA
2
9
1
SCK
8
Power over Ethernet Endpoint
switches and Midspans for IEEE Std
802.3af and 802.3at
Supports high-power PDs, such as:
Pan/Tilt/Zoom security cameras
802.11n WAPs
Multi-band, multi-radio WAPs
Security and RFID systems
22
MISO
7
Applications
24-Pin QFN
23
Supports classification-based and
LLDP power negotiation
Supports individual port priority and
port configuration
Supports Power supply status from
up to 3 power supplies
24 pin Quad flat pack package
(4x4 mm)
4x4 mm PCB footprint; RoHS
complaint
Extended operation range
(–40 to +85 °C)
24
Enables use of smaller power
supplies for up to 48-port PoE
systems with Si3452 PSE interface
ICs
Can operate with or without a host
Configuration save
Pin-selectable SPI or UART interface
Pin-selectable UART data rate
Fully-compliant with IEEE 802.3
clause 33 for PoE including the
802.3at amendment for higher power
(30 W, category 2 ports)
RSVD
16 BAUD0
15 BAUD1
See "5. Pin Descriptions" on page 31.
Description
The Si3452 is capable of delivering over 30 W per port, which means that, in a 24or 48-port system, a very large power supply would have to be used to avoid
overload. Typically, not all ports are used at full power; so, a smaller power supply
in the range of 5 W per port can be used along with the Si3482 power
management controller.
The Si3482 is a power manager intended for use with the Si3452/3 Power over
Ethernet (PoE) controllers for power management of up to 48 ports with three
power sources.
Use of the Si3482 power manager greatly simplifies system implementation of
power management. The Si3482 power management controller is programmed
via a SPI or UART interface to set the power supply capacity, the port power
configuration (Category 1: 15.4 W, or high-power category 2: 30 W) ports, the port
priority, the detection timing (Alternative A or Alternative B), and the fault recovery
protocol. Once programmed, the configuration data can be saved, and the Si3482
can work without host intervention. If desired, port and overall status information is
available and continuously updated.
The Si3482 uses the real-time overload and current monitoring capability of the
Si3452 to manage provided power among up to 48 ports. Power management is
selectable between grant-based or consumption-based in order to supply power
to the greatest number of ports.
In high-reliability systems, multiple power supplies are often connected to provide
redundancy, which further increases the power supply requirements. The Si3482
can manage up to three power supplies automatically enabling or disabling ports
in priority order when required.
Rev. 0.1 10/10
Copyright © 2010 by Silicon Laboratories
Si3482
Si3482
Functional Block Diagram
2
Rev. 0.1
Si3482
TABLE O F C ONTENTS
Section
Page
1. Electrical Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
2. Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6
2.1. Host Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
2.2. Hardware Only Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
3. Serial Packet Protocol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
3.1. Packet Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
3.2. SPP Error Handling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
4. Power Manager API . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
4.1. Management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
4.2. System Status . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
4.3. Port Status . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
4.4. System Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
4.5. Port Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22
4.6. System Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
4.7. Port Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
4.8. Power Supply Status . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .28
4.9. Events . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
4.10. Return Codes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
5. Pin Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
6. Package Outline: 24-Pin QFN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
7. PCB Land Pattern . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .34
8. Solder/Paste Recommendation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
9. Top Marking Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
10. Ordering Guide . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Contact Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .38
Rev. 0.1
3
Si3482
1. Electrical Specifications
Table 1. Recommended Operating Conditions
Description
Symbol
Test Conditions
Min
Typ
Max
Units
TA
No airflow
–40
—
85
°C
VDD
All operating modes
2.7
—
3.6
V
Min
Typ
Max
Units
Ambient Temperature
under Bias
–55
—
125
°C
Storage Temperature
–65
—
150
°C
–0.3
—
5.8
V
–0.3
—
4.2
V
Operating Temperature
Range
VDD Supply Voltage
Table 2. Absolute Maximum Ratings
Parameter
Conditions
Voltage on any I/O with
Respect to GND
VDD>2.2 V
Voltage on VDD with
Respect to GND
Note: Stresses above those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. This is a
stress rating only and functional operation of the devices at those or any other conditions above those indicated in the
operation listings of this specification is not implied. Exposure to maximum rating conditions for extended periods may
affect device reliability.
Table 3. Electrical Characteristics
Description
Symbol
Test Conditions
Min
Typ
Max
Units
Input High
VIH
2.0
—
—
V
Input Low
VIL
—
—
0.8
V
Input Leakage Current
IIL
Input pins:
RST, SCK, MOSI, NSS,
RX, PSn, BAUDn,
SLCTIN, SCL, SDA
—
—
±1
uA
Output Low
(MOSI, TX, SCL, and SDA)
VOL
IOL = 8.5 mA
—
—
0.6
V
Output High
(MOSI, TX)
VOH
IOH = –3 mA
—
—
VDD–0.7
V
VDD Current
IDD
VDD = 3.0 V*
VDD = 3.6 V*
—
—
8.6
12.1
mA
*Note: VDD = 2.7 to 3.6 V, –40 to 85 °C unless otherwise noted.
4
Rev. 0.1
Si3482
Table 4. Timing Requirements
Description
Test Conditions
Min
Max
Units
SPI Timing Requirements (See Figure 1)
TSE
NSS Falling to First SCK Edge
84
—
ns
TSD
Last SCK Edge to NSS Rising
84
—
ns
TSEZ
NSS Falling to MISO Valid
—
168
ns
TSDZ
NSS Rising to MISO High Z
—
168
ns
TCKH
SCK High Time
210
—
ns
TCKL
SCK Low Time
210
—
ns
TSIS
MOSI Valid to SCK Sample Edge
84
—
ns
TSIH
SCK Sample Edge to MOSI Change
84
—
ns
TSCH
SCK Shift Edge to MISO Change
—
168
ns
FMAX
Maximum SPI Clock Speed
—
1
MHz
UART Requirements (See Figure 2)
ΔFTx
Deviation of Tx Transmit Speed from Pin-programmed
Value.
–3
+3
%
ΔFRx
Deviation of Rx receive Speed from Pin-programmed
Value.
–4
+4
%
TSE
TCKH
TCKL
TSD
SCK
TSIH
MOSI
MSB
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
TSIS
MISO
MSB
TSEZ
TSCH
TSDZ
NSS
Figure 1. SPI Timing Diagram
MARK
SPACE
START
BIT
D0
D1
D2
D3
D4
D5
D6
D7
STOP
BIT
BIT TIMES
BIT SAMPLING
Figure 2. UART Timing Diagram
Rev. 0.1
5
Si3482
2. Functional Description
The Si3482 Power Management Controller is the central controller in a Silicon Labs Power over Ethernet (PoE)
system. In a PoE system, power is provided by one or more power supplies and is consumed by one or more
powered devices (PDs). The Si3482 decides which of the PDs can have power and monitors the amount of power
consumed by each.
A host microcontroller unit (MCU) can configure the Si3482 and can query the status of the PDs and the power
supplies. The Si3482 stores its configuration in internal flash memory. A host MCU uses a Universal Asynchronous
Receiver Transmitter (UART) or a Serial Peripheral Interface (SPI) to communicate with the Si3482. Pins on the
Si3482 select which host interface to use and which baud rate to use for the UART interface.
Power supplies may be inserted into bays. The Si3482 supports a system with up to three bays. Power supplies
may be inserted or removed from the bays at any time. Each bay provides a signal to the Si3482 that indicates if a
power supply is present in the bay. The outputs of the power supplies are ganged together to provide a single
power source for the system.
The Si3482 manages a collection of Si3452 Port Controllers. The Si3482 supports a system with up to 12 Si3452s.
Each Si3452 has four ports; so, a system may have up to 48 ports. The Si3452 performs low-level port functions,
such as detecting and classifying PDs. The Si3482 has a global view of the system and manages power across all
ports.
PDs are connected to ports on the Si3452s. PDs may be connected or disconnected from the ports at any time.
When a PD is connected to a port, then the PD requests power from the port. The Si3482 determines the amount
of power requested from the classification of the PD. If there is enough power remaining, the Si3482 grants the
request; otherwise, the Si3482 denies the request.
The host may configure an optional power limit for each port. A power limit restricts the amount of power that the
Si3482 grants to a port. If a power request is greater than the power limit, the Si3482 does not fully grant the
request, but only grants the amount of the power limit.
The Si3482 supports Link Layer Discovery Protocol (LLDP) agents in the host. An LLDP agent can call a routine in
the Si3482 to dynamically adjust the amount of power granted to a PD during the course of a connection.
Several PDs may be connected to a PoE system. The Si3482 may have granted different amounts of power to
each PD, and each PD may be consuming different amounts of power. If a PD consumes more power than it is
granted (port overload), the Si3482 turns off the PD.
There are two approaches that the Si3482 can take when granting requests for power. The granting policy can be
grant-based or it can be consumption-based.
Figure 3. Powered Devices Example
6
Rev. 0.1
Si3482
Figure 4. Grant Based Power Management
Figure 5. Consumption-Based Power Management
If the granting policy is grant based, then the power remaining for new grants is the total ungranted power. The
power remaining is the total power provided minus the total power granted.
The problem with this approach is that much of the provided power is unused because PDs often do not consume
all of their granted power.
If the granting policy is consumption-based, then the power remaining for new grants is the total unconsumed
power. The power remaining is the total power provided minus the total power consumed (excluding the reserved
power). This approach uses more of the provided power, but there is a possibility that the system may consume
more power than the power provided (system overload).
To avoid system overloads caused by momentary surges in power consumption, the host can specify that a certain
amount of power be held in reserve. The Si3482 does not use the reserved power when granting new requests.
Most power supplies can tolerate a limited amount of overload for a short duration. The host specifies the overload
limit of the power supplies to the Si3482. If a system overload is less than the overload limit, the Si3482 turns off
ports, one at a time in priority order, until the system is no longer overloaded. If a system overload is greater than
the overload limit (severe overload), the Si3482 immediately turns off all low-priority ports. If the system is still
overloaded, the Si3482 turns off additional ports, one at a time in priority order, until the system is no longer
overloaded. A severe overload is usually caused by removing a power supply.
2.1. Host Interface
The Si3482 has a UART interface and an SPI interface for communicating with the host MCU, but only one
interface is used at a time. The PSLCT (protocol select) pin selects which interface is used.
2.1.1. UART Interface
If the PSLCT pin is tied high, then the Si3482 uses the UART interface to communicate with the host MCU. The
Si3482 uses the TX and RX pins to send and receive serial data. The BAUD0, BAUD1, and BAUD2 pins select the
baud rate for the UART interface.
Rev. 0.1
7
Si3482
Table 5. Baud Rates
BAUD2
BAUD1
BAUD0
Baud Rate (bps)
H
L
L
19200
H
L
H
38400
H
H
L
57600
H
H
H
115200
The UART interface uses eight data bits, no parity, and one stop bit.
2.1.2. SPI Interface
If the PSLCT pin is tied low, then the Si3482 uses the SPI interface to communicate with the host MCU. The
Si3482 is an SPI slave device. Therefore, it receives data on the MOSI pin and sends data on the MISO pin. The
host MCU drives the NSS and SCK pins.
The SPI interface uses an active-high clock (CKPOL = 0). The clock line is low in the idle state, and the leading
edge of the clock goes from low to high. The SPI interface samples the data on the leading edge of the clock
(CKPHA = 0). The SPI interface transfers the most-significant bit first, and the maximum bit rate is 1 Mbps
2.2. Hardware Only Mode
The host interface (SPI or UART) and the UART baud rate are pin-configured. The Si3482 reads the pin
configuration at power up, and it cannot be changed after power up. The hardware designer only needs to decide
which interface to use and, if UART is selected, which BAUD rate to use.
In general, the host interface must be electrically isolated from the host MCU using an appropriate electrical
isolator for either SPI or UART signals as well as power supply status signals as needed.
The Si3482 backs up its configuration to internal flash memory. Once the Si3482 is configured, it is possible to
disconnect the host interface and use the Si3482 without a host MCU.
To configure the Si3482 when a host MCU is not required or for initial system debug, the USB adapter and Power
Manager GUI supplied with the Si3482 evaluation system, “SMARTPSE24-KIT”, can be adapted to set the device
configuration as desired.
8
Rev. 0.1
Si3482
3. Serial Packet Protocol
The Si3482 contains the Power Manager component and the interface to the Power Manager is a collection of
routines known as the Power Manager application programming interface (API).
The Power Manager API is described later in this manual. The host MCU contains a User Interface component,
which calls the routines in the Power Manager API to get status information and configure and control the Power
Manager.
The Serial packet protocol (SPP) is a remote procedure call (RPC) mechanism that allows a User Interface
component to call routines in the Power Manager, even though the User Interface component and the Power
Manager are on different MCUs. The Serial Packet Protocol is implemented by a Serial Packet Client in the host
MCU and the Serial Packet Server in the Si3482.
A Serial Packet Client is a collection of stub routines with the same names and parameters as the routines in the
Power Manager API. A User Interface component calls a stub routine, and the stub routine uses the host interface
to send a packet to the Serial Packet Server. The Serial Packet Client receives a packet back and then returns to
the User Interface component.
The Serial Packet Server receives a packet from a Serial Packet Client and then calls the specified routine in the
Power Manager. When the Power Manager routine returns, the Serial Packet Server sends a packet back to the
Serial Packet Client.
Silicon Labs provides a Serial Packet Client Software Development Kit (SDK) that implements SPP and is portable
to any MCU. The customer only needs to write some small support routines, which map SDK routines to RTOS
routines.
Host MCU
User Interface
Power Manager API
Serial Packet Client
UART or SPI
Serial Packet Protocol
(Remote Procedure Call)
Si3482
Serial Packet Server
Power Manager API
Power Manager
Si3482 Support
I2 C
Si3452
Figure 6. Serial Packet Protocol
Rev. 0.1
9
Si3482
3.1. Packet Format
A packet is a sequence of fields sent together as a unit. Figure 7 shows the SPP packet format.
Start Routine Data Length Data Checksum
Figure 7. Packet Format
Each field is a single byte except for the Data field. The Data field may be from zero to 255 bytes.
3.1.1. Start Field
The Start field marks the beginning of a packet and always contains the Start-of-Packet (SOP) character (0xAC). If
data is lost on the host interface, the Serial Packet Server and the Serial Packet Client use the Start field to
resynchronize. A “receive packet” routine starts by receiving and discarding bytes until the SOP character is found.
3.1.2. Checksum Field
The Checksum field is used to verify that the packet was not corrupted during transmission. The sender of a packet
calculates the checksum and writes it into the Checksum field. The receiver of a packet verifies that the checksum
is correct. The Checksum field should contain the value such that all the bytes in the packet, except for the Start
field, add up to zero.
Start Routine Data Length Data Checksum
Sum of Bytes is Zero
Figure 8. Packet Checksum
To calculate the checksum, the sender uses an 8-bit variable to sum up the bytes of the Routine field through the
end of the Data field. The sender adds one to the one's complement of this sum and stores the result in the
Checksum field.
Checksum = ~Sum + 1
To verify the checksum, the receiver uses an 8-bit variable to sum up the bytes of the Routine field through the
Checksum field. The sum should be zero.
3.1.3. Routine Field
The Routine field identifies a routine in the Power Manager API.
The client uses the Routine field to specify which routine to call. The client should verify that the Routine field in a
received packet matches the Routine field in the sent packet.
Table 6. Routine Field
10
Routine
Symbol
Value
GetSystemStatus()
RTN_GETSYSTEMSTATUS
1
GetSystemInfo()
RTN_GETSYSTEMINFO
2
GetTotalPowerConsumed()
RTN_GETTOTALPOWERCONSUMED
3
GetTotalPowerGranted()
RTN_GETTOTALPOWERGRANTED
4
GetTotalPowerProvided()
RTN_GETTOTALPOWERPROVIDED
5
GetPortCount()
RTN_GETPORTCOUNT
6
GetPortStatus()
RTN_GETPORTSTATUS
7
GetPortInfo()
RTN_GETPORTINFO
8
Rev. 0.1
Si3482
Table 6. Routine Field (Continued)
Routine
Symbol
Value
GetPortPriorityStatus()
RTN_GETPORTPRIORITYSTATUS
9
GetPortPowerConsumed()
RTN_GETPORTPOWERCONSUMED
10
GetPortPowerGranted()
RTN_GETPORTPOWERGRANTED
11
GetPortPowerRequested()
RTN_GETPORTPOWERREQUESTED
12
GetPortPowerAvailable()
RTN_GETPORTPOWERAVAILABLE
13
ResetSystem()
RTN_RESETSYSTEM
14
RestoreFactoryDefaults()
RTN_RESTOREFACTORYDEFAULTS
15
SetPortControl()
RTN_SETPORTCONTROL
16
AdjustPortPower()
RTN_ADJUSTPORTPOWER
17
SetPowerProvided()
RTN_SETPOWERPROVIDED
18
GetPowerProvided()
RTN_GETPOWERPROVIDED
19
SetReservedPower()
RTN_SETRESERVEDPOWER
20
GetReservedPower()
RTN_GETRESERVEDPOWER
21
SetOverloadLimit()
RTN_SETOVERLOADLIMIT
22
GetOverloadLimit()
RTN_GETOVERLOADLIMIT
23
SetGrantingPolicy()
RTN_SETGRANTINGPOLICY
24
GetGrantingPolicy()
RTN_GETGRANTINGPOLICY
25
SetRetryPolicy()
RTN_SETRETRYPOLICY
26
GetRetryPolicy()
RTN_GETRETRYPOLICY
27
SetPowerLocation()
RTN_SETPOWERLOCATION
28
GetPowerLocation()
RTN_GETPOWERLOCATION
29
SetPortEnable()
RTN_SETPORTENABLE
30
GetPortEnable()
RTN_GETPORTENABLE
31
SetPortCapability()
RTN_SETPORTCAPABILITY
32
GetPortCapability()
RTN_GETPORTCAPABILITY
33
SetPortPriority()
RTN_SETPORTPRIORITY
34
GetPortPriority()
RTN_GETPORTPRIORITY
35
SetPortPowerLimit()
RTN_SETPORTPOWERLIMIT
36
GetPortPowerLimit()
RTN_GETPORTPOWERLIMIT
37
SetPowerSupplyStatus()
RTN_SETPOWERSUPPLYSTATUS
38
GetPowerSupplyStatus()
RTN_GETPOWERSUPPLYSTATUS
39
GetEvents()
RTN_GETEVENTS
40
Rev. 0.1
11
Si3482
3.1.4. Data Length Field
The DataLength field specifies the number of bytes in the Data field. The number of bytes may be from zero to 255.
3.1.5. Data Field
The Data field is used to pass data to and from the Si3482. The Data field may contain four different types of data:
Parameters
System Information
Port Information
Events
The Data field has a different format for each type of data. In almost all packets (sent and received), the Data field
has the Parameters format. The only exceptions are the packets that are received back after calling the
GetSystemInfo(), GetPortInfo(), and GetEvents() routines. The Data fields for these packets are in the System
Information format, Port Information format, and Events format.
3.1.5.1. Parameters Format
The Parameters format of the Data field is used to pass parameters to Power Manager routines. In most cases, the
Parameters format is also used to return data from the routines.
Start Routine Data Length Data Checksum
Parm8
Parm32
Figure 9. Parameters Format
The Parameters format has an 8-bit Parm8 field followed by a 32-bit Parm32 field (see Table 7). Depending on the
routine being called, Parm8, Parm32, or both fields are used. Sometimes, neither field is used. However, both
fields are always sent and received. The DataLength field contains five.
Table 7. Use of Parameters
Parameters in Sent Packet
Parameters in Received Packet
Routine
Parm8
Parm32*
GetSystemStatus()
Parm8
SystemStatus
GetSystemInfo()
Uses System Information Format
GetTotalPowerConsumed()
PowerConsumed
GetTotalPowerGranted()
PowerGranted
GetTotalPowerProvided()
PowerProvided
GetPortCount()
PortCount
GetPortStatus()
Port
PortStatus
GetPortInfo()
Port
Uses Port Information Format
GetPortPriorityStatus()
Port
GetPortPowerConsumed()
Port
PowerConsumed
GetPortPowerGranted()
Port
PowerGranted
GetPortPowerRequested()
Port
PowerRequested
PortPriorityStatus
*Note: The Parm32 field is big endian; therefore, the most significant byte is first.
12
Parm32*
Rev. 0.1
Si3482
Table 7. Use of Parameters (Continued)
Parameters in Sent Packet
Parameters in Received Packet
Routine
Parm8
GetPortPowerAvailable()
Parm32*
Parm8
Port
Parm32*
PowerAvailable
ResetSystem()
Result
RestoreFactoryDefaults()
SetPortControl()
Port
Control
Result
AdjustPortPower()
Port
PortPower
Result
SetPowerProvided()
PowerSupply
PowerProvided
Result
GetPowerProvided()
PowerSupply
SetReservedPower()
ReservedPower
PowerProvided
Result
GetReservedPower()
SetOverloadLimit()
ReservedPower
OverloadLimit
Result
GetOverloadLimit()
SetGrantingPolicy()
OverloadLimit
GrantingPolicy
Result
GetGrantingPolicy()
SetRetryPolicy()
GrantingPolicy
RetryPolicy
Result
GetRetryPolicy()
SetPowerLocation()
RetryPolicy
PowerLocation
Result
GetPowerLocation()
PowerLocation
SetPortEnable()
Port
GetPortEnable()
Port
SetPortCapability()
Port
GetPortCapability()
Port
SetPortPriority()
Port
GetPortPriority()
Port
SetPortPowerLimit()
Port
GetPortPowerLimit()
Port
SetPowerSupplyStatus()
PowerSupply
GetPowerSupplyStatus()
PowerSupply
Enable
Result
Enable
Capability
Result
Capability
Priority
Result
Priority
PowerLimit
Result
PowerLimit
Status
Result
Status
GetEvents()
Uses Events Format
*Note: The Parm32 field is big endian; therefore, the most significant byte is first.
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3.1.5.2. System Information Format
The System Information format of the Data field is used to return system information to the client. System
information is returned after calling the GetSystemInfo() routine.
Start Routine Data Length Data Checksum
PowerManagerVersion PlatformSupportVersion
Figure 10. System Information Format
The System Information format has a PowerManagerVersion field followed by a PlatformSupportVersion field. Both
of these fields are eight bytes long and contain a version string that is a zero-terminated ASCII string. A version
string may be from one to seven characters long. The Routine field contains RTN_GETSYSTEMINFO, and the
DataLength field contains 16.
3.1.5.3. Port Information Format
The Port Information format of the Data field is used to return port information to the client. Port information is
returned after calling the GetPortInfo() routine.
Start Routine Data Length Data Checksum
Result Detection Classification Current
Power Supply Silicon Firmware
Voltage
Version Version
Figure 11. Port Information Format
In C, the Port Information format is:
typedef struct
{
INT8
Result;
UINT8
Detection;
UINT8
Classification;
UINT16 Current;
UINT16 PowerSupplyVoltage;
char
SiliconVersion[2];
char
FirmwareVersion[8];
} DATA_PORTINFO;
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The Port Information format is a sequence of fields as shown above. For more information, read the description of
the GetPortInfo() routine in the Power Manager API Section. The Routine field contains RTN_GETPORTINFO, and
the DataLength field contains 17.
The Result field contains the return code from the GetPortInfo() routine, and, if Result is not SUCCESS (0), the
remaining fields should be ignored.
The Current and PowerSupplyVoltage fields are big endian. Therefore, the most significant byte comes first.
3.1.5.4. Events Format
The Events format of the Data field is used to return events to the client. Events are returned after calling the
GetEvents() routine.
Start Routine Data Length Data Checksum
Event
Type
Event
Parm1
Event
...
Event
Parm2
Figure 12. Events Format
In the Si3482, the Serial Packet Server internally receives events from the Power Manager and stores them in a
circular event queue. If the event queue becomes full, newer events overwrite older events.
If a client wishes to receive events, it should periodically get the events from the Serial Packet Server. The client
gets the events by sending a packet with the Routine field set to RTN_GETEVENTS. The Serial Packet Server
returns all the events from the event queue in a single packet with the Data field in the Events format.
The Data field does not have a fixed length. The length of the Data field depends on the number of events that are
returned. An event is three bytes long; so, the number of events in the Data field is DataLength divided by three. If
there are no events to return, then DataLength is zero, and the Data field is empty. The maximum number of events
that can be returned is 85.
3.2. SPP Error Handling
There are many reasons why a client may not receive back a packet. Perhaps the Si3482 is not running or perhaps
the serial data was corrupted or lost during transmission (in either direction). In any case, it is not prudent for a
Serial Packet Client to call a serial receive routine that blocks forever until data is received. If the serial receive
routine does not have a timeout option, the client should not call the receive routine unless it knows that received
data is available. If a client does not receive a packet within one second of sending a packet, then the client should
assume that there has been a communications error. The client should resend the original packet or simply give up
(but do not wait forever to receive a packet).
When the Serial Packet Server receives a packet, it validates the packet. If the checksum is bad or the Routine
field is invalid, the Serial Packet Server ignores the packet and does not send back a packet in response. After one
second, the client should realize that a packet has not been received and should resend the original packet.
The Si3482 checks the configuration every 30 seconds to see if it has changed. If the configuration has changed,
the Si3482 backs up the configuration to internal flash memory. While the Si3482 is writing to flash memory, it
cannot send or receive packets on the host interface. If a host MCU sends a packet to the Si3482 while it is backing
up the configuration, the packet is lost. If a host MCU does not receive a packet back within one second, the host
MCU should resend the original packet.
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4. Power Manager API
User Interface components call the routines in the Power Manager API to get status information and configure and
control the Power Manager. The Power Manager API has routines for:
Management
System Status
Port Status
System Control
Port Control
System Configuration
Port Configuration
Power Supply Status
Events
4.1. Management
The Management routines allow a User Interface component to:
Initialize the Serial Packet Client
Close the Serial Packet Client
4.1.1. InitPowerManager
Initialize the Serial Packet Client.
Prototype:
INT8 InitPowerManager ( EVENT_HANDLER EventHandler )
Parameters:
EventHandler
Return Value:
Zero (for success) or an error code.
A pointer to an event handler routine.
This is the first call that a User Interface component makes to the Serial Packet Client. The Serial Packet Client
does everything that is required to bring itself to an operational state and is ready to execute all other Power
Manager API routines.
If a User Interface component would like to receive events, it should pass the address of an event handler to this
routine. If a User Interface component does not want to receive events, it should pass a null address to this routine.
An event handler is located in a User Interface component and has the following prototype:
Prototype:
void EventHandler ( EVENT *Event )
Parameters:
Event
Return Value:
None
A pointer to an EVENT structure, where event information is provided.
An EVENT structure has the following layout:
typedef struct
{
UINT8
Type;
INT8
Parm1;
UINT8
Parm2;
} EVENT;
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Table 8 lists the event type values.
Table 8. Event Types
Event Type
Value
Symbol
Parm1
Parm2
System
1
SYSTEM_EVENT
System Status
(not used)
Port
2
PORT_EVENT
Port Status
Port Number
Power Supply
4
POWER_SUPPLY_EVENT
Power Supply Status
Power Supply Number
Error
8
ERROR_EVENT
Error Code
(error specific)
Information
16
INFO_EVENT
Information Code
(not used)
See the GetSystemStatus(), GetPortStatus(), and GetPowerSupplyStatus() routines for a listing of the status
values. See the end of this section for a listing of error codes and information codes.
The Serial Packet Client calls the event handler whenever there is a change in system status, port status, or power
supply status. The event handler is also called when an error occurs, such as port overload. If the first parameter
(Parm1) is negative, this means there is an error.
4.1.2. ClosePowerManager
Shut down the Serial Packet Client.
Prototype:
void ClosePowerManager ( void )
Parameters:
None
Return Value:
None
This function shuts down the Serial Packet Client and frees all allocated resources.
4.2. System Status
The System Status routines allow a User Interface component to get the following information:
System Status
System Info
Total Power Consumed
Total Power Granted
Total Power Provided
4.2.1. GetSystemStatus
Get the status of the system.
Prototype:
INT8 GetSystemStatus( void )
Parameters:
None
Return Value:
System status value.
Table 9 lists the system status values. The system status is the overall status of the system. A negative system
status value is an error that is not specific to a particular port.
Table 9. System Status
Status
Value
Symbol
OK
0
STATUS_SYSTEM_OK
Initialization Failed
–1
STATUS_SYSTEM_INIT_FAIL
Under Voltage
–2
STATUS_SYSTEM_UNDER_VOLT
Over Temperature
–3
STATUS_SYSTEM_OVER_TEMP
Communications Lost
–4
STATUS_SYSTEM_COMM_LOST
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4.2.2. GetSystemInfo
Get information about the system.
Prototype:
void GetSystemInfo ( SYSINFO *SystemInfo )
Parameters:
SystemInfo
Return Value:
None
A pointer to a SYSINFO structure, where the system information is returned.
A SYSINFO structure has the following layout:
typedef struct
{
char
*PowerManagerVersion;
char
*PlatformSupportVersion;
} SYSINFO;
The SYSINFO structure contains the version of the Power Manager and the version of the Platform Support
component as zero-terminated strings.
4.2.3. GetTotalPowerConsumed
Get the power consumed by all PDs.
Prototype:
INT32 GetTotalPowerConsumed ( void )
Parameters:
None
Return Value:
Total power consumed in milliwatts.
4.2.4. GetTotalPowerGranted
Get the power granted to all PDs.
Prototype:
INT32 GetTotalPowerGranted ( void )
Parameters:
None
Return Value:
Total power granted in milliwatts.
4.2.5. GetTotalPowerProvided
Get the power provided by all power supplies.
Prototype:
INT32 GetTotalPowerProvided ( void )
Parameters:
None
Return Value:
Total power provided in milliwatts.
4.3. Port Status
The Port Status routines allow a User Interface component to get the following:
Port Count
Port Status
Port Info
Port Priority Status
Port Power Consumed
Port Power Granted
Port Power Requested
Port Power Available
4.3.1. GetPortCount
Get the number of ports in the system.
Prototype:
UINT8 GetPortCount ( void )
Parameters:
None
Return Value:
Number of ports in the system.
When the Power Manager starts up, it discovers the number of ports in the system by searching for port controllers.
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4.3.2. GetPortStatus
Get the status of a port.
Prototype:
INT8 GetPortStatus ( UINT8 Port )
Parameters:
Port
Return Value:
Port status value or an error code.
The port number (1–48)
Table 10 lists the Port status values.
Table 10. Port Status Values
Status
Value
Symbol
Description
Disabled
0
STATUS_PORT_DISABLED
Powered On
1
STATUS_PORT_POWERED_ON
A PD is connected and receiving power.
Powered Off
2
STATUS_PORT_POWERED_OFF
The port is off because a PD is not connected.
Denied
3
STATUS_PORT_DENIED
Blocked
4
STATUS_PORT_BLOCKED
Forced On
5
STATUS_PORT_FORCED_ON
The user forced the port on.
Forced Off
6
STATUS_PORT_FORCED_OFF
The user forced the port off.
The port is off because it is not allowed to
turn on.
The port is off because there is not enough
power remaining to grant the power request.
The port is off because of a port overload.
If a port is blocked, then the PD consumed more power than it was granted (port overload), and the retry policy is
“retry after reconnect”. To remove the block, the user must physically disconnect the PD from the port. Another way
to remove the block is to disable and then reenable the port.
4.3.3. GetPortInfo
Get low-level port information.
Prototype:
INT8 GetPortInfo ( UINT8 Port, PORTINFO *PortInfo )
Parameters:
Port
The port number (1–48)
PortInfo
A pointer to a PORTINFO structure, where the port information is returned.
Return Value:
Zero (for success) or an error code
A PORTINFO structure has the following layout:
typedef struct
{
UINT8
Detection;
UINT8
Classification;
UINT16
Current;
/* in mA */
UINT16
PowerSupplyVoltage;
/* in mV */
char
*SiliconVersion;
char
*FirmwareVersion;
} PORTINFO;
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Si3482
Table 11 lists Detection values.
Table 11. Detection Values
Detection
Value
Symbol
Unknown
0
DETECT_UNKNOWN
Short
1
DETECT_SHORT
Low
3
DETECT_LOW
Good
4
DETECT_GOOD
High
5
DETECT_HIGH
Open
6
DETECT_OPEN
Table 12 lists Classification values.
Table 12. Classification Values
Classification
Value
Symbol
Unknown
0
CLASS_UNKNOWN
Class 1
1
CLASS_1
Class 2
2
CLASS_2
Class 3
3
CLASS_3
Class 4
4
CLASS_4
Fingers Not Equal
5
CLASS_UNEQ_FINGERS
Class 0
6
CLASS_0
Overload
7
CLASS_OVERLOAD
4.3.4. GetPortPriorityStatus
Get the priority status of a port.
Prototype:
INT8 GetPortPriorityStatus ( UINT8 Port )
Parameters:
Port
Return Value:
Port priority status value or an error code.
20
The port number (1–48)
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Table 13 lists the Port Priority Status values.
Table 13. Port Priority Status Values
Port Priority Status
Value
Symbol
Low
0
PRIORITY_LOW
High
1
PRIORITY_HIGH
Forced
2
PRIORITY_FORCED
Critical
3
PRIORITY_CRITICAL
The priority status of a port is the currently-active priority and may be different than the configured priority of the
port. If a port is forced on or off and the configured priority is low or high, the priority status is elevated to the forced
priority. If a forced port is returned to automatic control, the Power Manager returns the priority status to the
configured priority.
4.3.5. GetPortPowerConsumed
Get the power that a PD is currently using.
Prototype:
INT32 GetPortPowerConsumed ( UINT8 Port )
Parameters:
Port
Return Value:
Port power consumed in milliwatts or an error code.
The port number (1–48)
4.3.6. GetPortPowerGranted
Get the power that is allocated to a PD.
Prototype:
INT32 GetPortPowerGranted ( UINT8 Port )
Parameters:
Port
Return Value:
Port power granted in milliwatts or an error code.
The port number (1–48)
4.3.7. GetPortPowerRequested
Get the power that a PD says it needs.
Prototype:
INT32 GetPortPowerRequested ( UINT8 Port )
Parameters:
Port
Return Value:
Port power requested in milliwatts or an error code.
The port number (1–48)
4.3.8. GetPortPowerAvailable
Get the maximum request that would be successfully granted.
Prototype:
INT32 GetPortPowerAvailable ( UINT8 Port )
Parameters:
Port
Return Value:
Port power available in milliwatts or an error code.
The port number (1–48)
An LLDP agent calls this routine to ask the question, “What is the maximum power that you would give me if I
asked for it?”
If a port has a power limit, then the power limit is returned. If a port does not have a power limit and the port can
supply high power, then maximum power (40 W) is returned; otherwise, low power (15.4 W) is returned.
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4.4. System Control
The System Control routines allow a User Interface component to
Reset the System
Restore Factory Defaults
4.4.1. ResetSystem
Reset the system.
Prototype:
INT8 ResetSystem ( void )
Parameters:
None
Return Value:
Zero (for success) or an error code.
4.4.2. RestoreFactoryDefaults
Restore the configuration to factory default values.
Prototype:
void RestoreFactoryDefaults ( void )
Parameters:
None
Return Value:
None
The Power Manager also resets the system after setting the configuration to default values.
4.5. Port Control
The Port Control routines allow a User Interface component to
Set Port Control
Adjust Port Power
4.5.1. SetPortControl
Set how the port is turned on and off.
Prototype:
INT8 SetPortControl ( UINT8 Port, UINT8 Control )
Parameters:
Port
Control
Return Value:
Zero (for success) or an error code.
The port number (1–48)
How the port is turned on and off.
Table 14 lists Port Control values.
Table 14. Port Control Values
Control
Value
Symbol
Automatic
0
PORT_CTRL_AUTOMATIC
Force On
1
PORT_CTRL_FORCE_ON
Force Off
2
PORT_CTRL_FORCE_OFF
If the port control is automatic, the Power Manager automatically turns the port on and off when a PD is connected
and disconnected from the port.
If the port control is forced on, the port's priority is boosted to the forced priority level. This usually results in the port
turning on. However, a forced port cannot cause a critical priority port to turn off in order to turn on the forced port.
If a forced port is granted power, the Power Manager turns on a forced port even if no PD is detected.
If the port control is forced off, the port is unconditionally turned off and held off. A forced-off port is considered to
be temporarily off, while a disabled port is considered to be permanently off.
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4.5.2. AdjustPortPower
Adjust the power granted to a PD.
Prototype:
INT8 AdjustPortPower ( UINT8 Port, INT32 Power )
Parameters:
Port
Power
Return Value:
Zero (for success) or an error code.
The port number (1–48)
Requested port power in milliwatts.
An LLDP agent calls this routine to reallocate the power granted to a PD. The agent can request more power than
is currently granted or it can request less power than is currently granted. This routine allows an LLDP agent to
dynamically change the amount of power granted to a PD during the course of a connection. A port must be on
before its power can be adjusted.
4.6. System Configuration
The System Configuration routines allow a User Interface component to set and get
Power Provided
Reserved Power
Overload Limit
Granting Policy
Retry Policy
Power Location
4.6.1. SetPowerProvided
Set the amount of power that is output from a power supply.
Prototype:
INT8 SetPowerProvided ( UINT8 PowerSupply, INT32 Power )
Parameters:
PowerSupply
Power
Return Value:
Zero (for success) or an error code.
The power supply number (1–3)
Power provided by the power supply in milliwatts.
4.6.2. GetPowerProvided
Get the amount of power that is output from a power supply.
Prototype:
INT32 GetPowerProvided ( UINT8 PowerSupply )
Parameters:
PowerSupply
Return Value:
Power provided by the power supply in milliwatts or an error code.
The power supply number (1–3)
4.6.3. SetReservedPower
Set the percentage of power that is reserved from granting.
Prototype:
INT8 SetReservedPower ( INT8 Reserved )
Parameters:
Reserved
Return Value:
Zero (for success) or an error code.
Reserved power as a percentage of the total power provided.
If the granting policy is consumption-based, the Power Manager holds this amount of power in reserve. The Power
Manager does not use the reserved power to grant new requests. This creates a power buffer that reduces the
likelihood of system overloads caused by momentary surges in consumption.
4.6.4. GetReservedPower
Get the percentage of power that is reserved from granting.
Prototype:
INT8 GetReservedPower ( void )
Parameters:
None
Return Value:
Reserved power as a percentage of the total power provided or an error code.
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Si3482
4.6.5. SetOverloadLimit
Set the maximum system overload that the power supplies can tolerate.
Prototype:
INT8 SetOverloadLimit ( INT8 Limit )
Parameters:
Limit
Return Value:
Zero (for success) or an error code.
Overload limit as a percentage of the total power provided.
The overload limit is the maximum system overload that the power supplies can tolerate. It is expressed as a
percentage of the total power provided. If a system overload is less than the overload limit, the ports are turned off
one at a time. If a system overload is greater than the overload limit (severe overload), all of the low-priority ports
are immediately turned off.
4.6.6. GetOverloadLimit
Get the maximum system overload that the power supplies can tolerate.
Prototype:
INT8 GetOverloadLimit ( void )
Parameters:
None
Return Value:
Overload limit as a percentage of the total power provided or an error code.
4.6.7. SetGrantingPolicy
Set the granting policy.
Prototype:
INT8 SetGrantingPolicy ( INT8 GrantingPolicy )
Parameters:
GrantingPolicy
Return Value:
Zero (for success) or an error code.
How requests for power are granted.
Table 15 lists the Granting Policy values.
Table 15. Granting Policy Values
Granting Policy
Value
Symbol
Grant-based
0
GRANT_POLICY_GRANT_BASED
Consumption-based
1
GRANT_POLICY_CONSUMPTION_BASED
The granting policy is used by the Power Manager when deciding if a request for power should be granted. If the
granting policy is grant based, the remaining power is considered to be the total ungranted power. If the granting
policy is consumption-based, the remaining power is considered to be the total unconsumed power (excluding the
reserved power). If the remaining power is greater than or equal to the requested power, then the Power Manager
grants the request.
Grant based:
PowerRemaining = TotalPowerProvided – TotalPowerGranted
Consumption based:
PowerRemaining = TotalPowerProvided – TotalPowerConsumed –
ReservedPower
4.6.8. GetGrantingPolicy
Get the granting policy.
Prototype:
INT8 GetGrantingPolicy ( void )
Parameters:
None
Return Value:
The granting policy value.
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4.6.9. SetRetryPolicy
Set the retry policy.
Prototype:
INT8 SetRetryPolicy ( INT8 RetryPolicy )
Parameters:
RetryPolicy
Return Value:
Zero (for success) or an error code.
When to retry after a port overload.
Table 16 lists the Retry policy values.
Table 16. Retry Policy Values
Retry Policy
Value
Symbol
Immediate
0
RETRY_IMMEDIATELY
Reconnect
1
RETRY_AFTER_RECONNECT
Reenable
2
RETRY_AFTER_REENABLE
The retry policy specifies when the Power Manager tries again to power a port that is turned off because of a port
overload. A port overload is when the power consumed by a PD is greater than the power granted to that PD. If the
retry policy is “immediate”, the Power Manager tries to turn the port back on immediately.
If the retry policy is “reconnect”, the Power Manager waits until the PD is disconnected and then reconnected
before it tries again to power the port. The Power Manager must detect an open circuit on the port before retrying.
If the retry policy is “reenable”, the Power Manager disables the port when a port overload occurs. The user must
reenable the port before the Power Manager tries to power the port again.
4.6.10. GetRetryPolicy
Get the retry policy.
Prototype:
INT8 GetRetryPolicy ( void )
Parameters:
None
Return Value:
The retry policy value.
4.6.11. SetPowerLocation
Set the location of the power source.
Prototype:
INT8 SetPowerLocation ( INT8 Location )
Parameters:
Location
Return Value:
Zero (for success) or an error code.
Where the power source is located.
Table 17 lists the Location values.
Table 17. Power Location Values
Location
Value
Symbol
Endpoint
0
LOCATION_ENDPOINT
Midspan
1
LOCATION_MIDSPAN
If the power source is within an Ethernet switch, the location is an “endpoint”. If the power source is inserted
between an Ethernet switch and a PD, the location is a “midspan”. The Power Manager uses different back-off
timings for different locations. The Power Manager assumes that an endpoint device uses the Alternative A pinout
and that a midspan device uses the Alternative B pinout.
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4.6.12. GetPowerLocation
Get the location of the power source.
Prototype:
INT8 GetPowerLocation ( void )
Parameters:
None
Return Value:
The location value.
4.7. Port Configuration
The Port Configuration routines allow a User Interface component to set and get:
Port Enable
Port Capability
Port Priority
Port Power Limit
4.7.1. SetPortEnable
Set if a port is allowed to turn on.
Prototype:
INT8 SetPortEnable ( UINT8 Port, INT8 Enable )
Parameters:
Port
Enable
Return Value:
Zero (for success) or an error code
The port number (1–48)
Specifies if the port is allowed to power on.
If Enable is zero, the port is disabled and is not allowed to power on. If Enable is one, the port is enabled and is
allowed to power on.
4.7.2. GetPortEnable
Get if a port is allowed to turn on.
Prototype:
INT8 GetPortEnable ( UINT8 Port )
Parameters:
Port
Return Value:
Zero for disabled, one for enabled, or an error code
The port number (1–48)
4.7.3. SetPortCapability
Set if a port can supply high power.
Prototype:
INT8 SetPortCapability ( UINT8 Port, INT8 Capability )
Parameters:
Port
The port number (1–48)
Capability Specifies if the port can supply high power.
Return Value:
Zero (for success) or an error code
Table 18 lists the Port Capability values.
Table 18. Port Capability Values
Capability
Value
Symbol
Low Power
0
CAPABILITY_LOW_POWER
High Power
1
CAPABILITY_HIGH_POWER
If the port hardware is designed to supply high power (PoE+), set Capability to one. Otherwise, set
Capability to zero.
A port's capability cannot be changed while the port is on. This is a limitation of the Si3452 port controller.
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4.7.4. GetPortCapability
Get if a port can supply high power.
Prototype:
INT8 GetPortCapability ( UINT8 Port )
Parameters:
Port
Return Value:
Capability value or an error code
The port number (1–48)
4.7.5. SetPortPriority
Set the priority of a port.
Prototype:
INT8 SetPortPriority ( UINT8 Port, INT8 Priority )
Parameters:
Port
Priority
Return Value:
Zero (for success) or an error code
The port number (1–48)
How important it is for the port to be powered.
Table 19 lists the Port priority values.
Table 19. Port Priority Values
Port Priority
Value
Symbol
Low
0
PRIORITY_LOW
High
1
PRIORITY_HIGH
Critical
3
PRIORITY_CRITICAL
The priority of a port indicates how important it is that the port receives power. If there is not enough power
provided for all ports that want power, then the low priority ports are the first ports to be denied. Critical priority ports
are the last ports to be denied.
If a port is forced on, then the port's priority is elevated to the forced priority level. Forced priority is between high
priority and critical priority and cannot be directly set by the user. When a port is forced on, it may cause a high
priority port to be turned off, but it can never cause a critical priority port to be turned off.
If a severe overload occurs, all of the low priority ports are immediately powered off.
4.7.6. GetPortPriority
Get the priority of a port.
Prototype:
INT8 GetPortPriority ( UINT8 Port )
Parameters:
Port
Return Value:
Priority value or an error code
The port number (1–48)
4.7.7. SetPortPowerLimit
Set the power limit of a port.
Prototype:
INT8 SetPortPowerLimit ( UINT8 Port, INT32 Limit )
Parameters:
Port
Limit
Return Value:
Zero (for success) or an error code.
The port number (1–48)
Maximum power that may be granted in milliwatts.
A power limit restricts the amount of power that may be granted to a port. If a port's power limit is zero, the Power
Manager grants the power requested without restriction. If a port's power limit is greater than zero, the Power
Manager grants the lesser of the power limit or the power requested. If a power request is greater than the power
limit, the Power Manager grants less power than requested.
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4.7.8. GetPortPowerLimit
Get the power limit of a port.
Prototype:
INT32 GetPortPowerLimit ( UINT8 Port )
Parameters:
Port
Return Value:
Power limit in milliwatts or an error code
The port number (1–48)
4.8. Power Supply Status
The Power Supply Status routines allow a User Interface component to get:
Power Supply Status
4.8.1. SetPowerSupplyStatus
Set the status of a power supply.
Prototype:
INT8 SetPowerSupplyStatus (UINT8 PowerSupply, INT8 Status)
Parameters:
PowerSupply
Status
Return Value:
Zero (for success) or an error code.
The power supply number (1–3)
Power supply status
In platforms that do not have signals to indicate the presence of power supplies, this routine allows a User Interface
component to simulate the insertion and removal of power supplies. However, the Si3482 does have power supply
signals (PS1, PS2, and PS3). If a User Interface component calls this routine, the Power Manager does nothing
and returns SUCCESS.
4.8.2. GetPowerSupplyStatus
Get the status of a power supply.
Prototype:
INT8 GetPowerSupplyStatus ( UINT8 PowerSupply )
Parameters:
PowerSupply
Return Value:
The status of the power supply.
The power supply number (1–3)
Table 20 lists the Power supply status values.
Table 20. Power Supply Status
Power Supply Status
Value
Symbol
Removed
0
STATUS_POWER_SUPPLY_REMOVED
Inserted
1
STATUS_POWER_SUPPLY_INSERTED
A User Interface component calls this function to determine whether a power supply is present in a bay. If the
voltage on the specified power supply pin (PS1, PS2, or PS3) is high, this routine returns
STATUS_POWER_SUPPLY_INSERTED; otherwise, this routine returns STATUS_POWER_SUPPLY_REMOVED.
28
Rev. 0.1
Si3482
4.9. Events
An event is an unsolicited notification from the Power Manager that a status has changed. The Power Manager
calls the event handler in the Serial Packet Server whenever there is a change in system status, port status, or
power supply status. The Serial Packet Server stores the events in an event queue.
Host MCU
User Interface
EventHan dler()
Serial Packet
Event
Task
Client
Si3482
Serial Packet
GetEvents ()
Server
Event
Queue
EventH an dler()
Power Manager
Figure 13. Events Architecture
If a User Interface component wishes to receive events, it provides the address of an event handler when it calls
InitPowerManager(). The Serial Packet Client spawns an event task. The event task remotely calls the GetEvents()
routine in the Serial Packet Server every 200 ms to retrieve the events from the event queue. For each event that
is retrieved, the Serial Packet Client calls the event handler in the User Interface component.
4.9.1. GetEvents
Get the events from the event queue.
Prototype:
void GetEvents ( EVENT *Event )
Parameters:
Event
Return Value:
None.
Pointer to returned events.
This routine exists in the Serial Packet Server and is called by a Serial Packet Client to get events from the event
queue. This routine sends back a packet with the Data field in the Events format. This routine may return from zero
to 85 events.
Rev. 0.1
29
Si3482
4.10. Return Codes
The routines of the Power Manager API return codes to indicate the success or failure of an operation. These
codes are also used in Parm1 of error events and information events.
4.10.1. Success Code
A zero code indicates success.
Table 21. Success Code
Success
Value
Symbol
Success
0
SUCCESS
4.10.2. Error Codes
A negative code indicates an error.
Table 22. Error Codes
Error
Value
Symbol
Port number is invalid
–1
ERROR_PORT_INVALID
Power supply number is invalid
–2
ERROR_PWR_SUPLY_INVALID
Parameter is invalid
–3
ERROR_PARAMETER_INVALID
Cannot create resource
–4
ERROR_RESOURCE_CREATE
Resource is invalid
–5
ERROR_RESOURCE_INVALID
Cannot configure resource
–6
ERROR_RESOURCE_CONFIG
Cannot read from resource
–7
ERROR_RESOURCE_READ
Cannot write to resource
–8
ERROR_RESOURCE_WRITE
Cannot find the resource
–9
ERROR_RESOURCE_NOT_FND
Cannot load the configuration
–10
ERROR_CONFIG_LOAD
Cannot save the configuration
–11
ERROR_CONFIG_SAVE
Configuration data is invalid
–12
ERROR_CONFIG_INVALID
Configuration data is corrupt
–13
ERROR_CONFIG_CORRUPT
System overload
–14
ERROR_SYSTEM_OVERLOAD
Port overload
–15
ERROR_PORT_OVERLOAD
Startup overload
–16
ERROR_STARTUP_OVERLOAD
4.10.3. Information Codes
A positive code indicates useful information.
Table 23. Information Codes
30
Information
Value
Symbol
Restored to factory defaults
1
INFO_DEFAULTS_RESTORED
System reset
2
INFO_SYSTEM_RESET
Configuration saved
3
INFO_CONFIG_SAVED
Rev. 0.1
Si3482
MOSI
NSS
TX
RX
RSVD
INT
5. Pin Descriptions
24
23
22
21
20
19
MISO
1
18 SDA
SCK
2
17 SCL
GND
3
Top View
(Pads on Bottom of Package)
16 BAUD0
6
13 PSLCT
7
8
9
10
11
12
PS1
RSVD
PS2
14 BAUD2
PS3
5
RSVD
RST
RSVD
4
RSVD
VDD
15 BAUD1
Table 24. Si3482 Pin Descriptions
Pin #
Name
Type
Description
1
MISO
Output
SPI output.
2
SCK
Input
SPI clock.
3
GND
Power
Ground.
4
VDD
Power
VDD.
5
RST
Input
Reset (a low will reset the Si3480).
6
RSVD
Input
Reserved—tie low.
7
RSVD
Reserved
Do not connect.
8
RSVD
Reserved
Do not connect.
9
RSVD
Reserved
Do not connect.
10
PS3
Input
Logic high indicates the power supply is available.
11
PS2
Input
Logic high indicates the power supply is available.
12
PS1
Input
Logic high indicates the power supply is available.
13
PSLCT
Input
Tie high or low to select between SPI and UART interface.
14
BAUD2
Input
Tie high or low to select UART baud rate.
15
BAUD1
Input
Tie high or low to select UART baud rate.
Rev. 0.1
31
Si3482
Table 24. Si3482 Pin Descriptions (Continued)
32
Pin #
Name
Type
Description
16
BAUD0
Input
17
SCL
Open Collector Connect to Si3452 SCL and pull up resistor.
18
SDA
Open Collector Connect to Si3452 SDA and pull up resistor.
19
INT
Input
20
RSVD
Reserved
Do not connect.
21
RX
Input
UART receive.
22
TX
Output
UART transmit.
23
NSS
Input
SPI select.
24
MOSI
Input
SPI input.
Tie high or low to select UART baud rate.
Connect to Si3452 INT and pull up resistor.
Rev. 0.1
Si3482
6. Package Outline: 24-Pin QFN
The Si3482 is packaged in an industry-standard, RoHS-compliant 6 x 6 mm2, 24-pin QFN package.
Bottom View
12
11
10
9
8
7
E/2
R
13
D2 / 2
14
15
D2
4
3
16
D
e
5
5xe
b
L
6
E2 / 2
17
E2
19
20
21
22
18
23
1
24
Pin #1 ID
D/2
2
5xe
E
A
A2
Side View
A1
A3
e
Figure 14. 24-Pin QFN Mechanical Diagram
Table 6.1. QFN-24 Package Dimensions
A
A1
A2
A3
b
D
D2
E
E2
e
L
N
ND
NE
R
Min
0.70
0.00
—
—
0.18
—
2.50
—
2.50
—
0.35
—
—
—
0.09
MM
Typ
0.75
0.02
0.50
0.25
0.25
4.00
2.60
4.00
2.60
0.50
0.40
24
6
6
—
Rev. 0.1
Max
0.80
0.05
—
—
0.30
—
2.70
—
2.70
—
0.45
—
—
—
—
33
Si3482
7. PCB Land Pattern
0.35 mm
0.45 mm
e
Pin #1
0.10 mm
0.75 mm
Top View
b
E2
0.20 mm
0.30 mm
0.35 mm
0.75 mm
0.45 mm
0.10 mm
E
Figure 15. Typical QFN-24 PCB Land Pattern
34
Rev. 0.1
D
D2
Optional
GND
Connection
Si3482
8. Solder/Paste Recommendation
0.35 mm
0.45 mm
Pin #1
0.45 mm
e
0.60 mm
0.10 mm
0.75 mm
Top View
0.30 mm
0.80 mm
0.20 mm
b
D
0.35 mm
D2
0.35 mm
E2
0.20 mm
0.30 mm
0.35 mm
0.75 mm
0.45 mm
0.10 mm
E
Figure 16. QFN-24 Solder Paste Recommendation
Rev. 0.1
35
Si3482
9. Top Marking Diagram
3482A
01
TTTTT
YYWW+
Figure 17. Top Marking Diagram
Table 25. Top Marking Explanation
Pin 1 Identifier
Circle, 0.25 mm diameter
Product ID
3482A
Line 2 Marking:
Firmware revision
01 = Firmware revision 01
Line 3 Marking:
TTTTT = Trace Code
Manufacturing code characters from the
Markings section of the Assembly Purchase
Order form
YYWW+ = Date Code
YY = Last two digits of current year
WW = Current Work Week
Lead Free Designator
+
Line 1 Marking:
Line 4 Marking:
36
Rev. 0.1
Si3482
10. Ordering Guide
Table 26. Si3482 Ordering Guide
Ordering Part Number
Description
Package Information
Si3482-A01-GM
Power management controller
24-pin 4x4 mm QFN
RoHS compliant
SMARTPSE24-KIT
An evaluation kit with the Si3482, six Si3452 controllers, and the Si3500 for generating the 3.3 V
supply from the PoE supply.
Evaluation Board
Notes:
1. Add “R” to the part number to denote tape and reel option (Si3482-A01-GMR).
2. The ordering part number is not the same as the device mark. See "6. Package Outline: 24-Pin QFN" on page 33 for
device marking information
Rev. 0.1
37
Si3482
CONTACT INFORMATION
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400 West Cesar Chavez
Austin, TX 78701
Tel: 1+(512) 416-8500
Fax: 1+(512) 416-9669
Toll Free: 1+(877) 444-3032
Please visit the Silicon Labs Technical Support web page:
https://www.silabs.com/support/pages/contacttechnicalsupport.aspx
and register to submit a technical support request.
The information in this document is believed to be accurate in all respects at the time of publication but is subject to change without notice.
Silicon Laboratories assumes no responsibility for errors and omissions, and disclaims responsibility for any consequences resulting from
the use of information included herein. Additionally, Silicon Laboratories assumes no responsibility for the functioning of undescribed features
or parameters. Silicon Laboratories reserves the right to make changes without further notice. Silicon Laboratories makes no warranty, representation or guarantee regarding the suitability of its products for any particular purpose, nor does Silicon Laboratories assume any liability
arising out of the application or use of any product or circuit, and specifically disclaims any and all liability, including without limitation consequential or incidental damages. Silicon Laboratories products are not designed, intended, or authorized for use in applications intended to
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38
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