TI1 LM4308SQ/NOPB Lm4308 mobile pixel link two (mpl-2) â 18-bit cpu display interface master/slave Datasheet

LM4308
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SNLS225C – AUGUST 2007 – REVISED MAY 2013
LM4308 Mobile Pixel Link Two (MPL-2) – 18-bit CPU Display Interface Master/Slave
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FEATURES
DESCRIPTION
•
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•
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•
•
•
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•
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•
The LM4308 device adapts a 18-bit CPU style display
interfaces to a MPL-2 SLVS differential serial link for
displays. Two chip selects support a main and sub
display up to and beyond 640 x 480 pixels. A mode
pin configures the device as a Master (MST) or Slave
(SLV). Both WRITE and READ operations are
supported. CPU interface widths below 18-bits are
supported by tieing unused inputs to a static level.
1
2
•
•
•
18-bit i80 CPU Display Interface
Supports up to 640 x 480 VGA Formats
Differential SLVS Interface
Dual Displays Supported
WRITE and READ Operations Supported
Robust Differential Physical Layer
400mVpp Differential Signal Swing
Internal 100 Ω Termination Resistor
Low Power Consumption
5-bit CRC for Data Integrity
Level Translation between Host and Display
Low Power Sleep State
3.3V Tolerant Master Clock Input Regardless
of VDDIO
Fast Start Up Time - 1k CLK Cycles
1.6V to 2.0V Core / Analog Supply Voltage
1.6V to 3.0V I/O Supply Voltage Range
SYSTEM BENEFITS
•
•
•
•
The differential line drivers and receivers conform to
the JEDEC SLVS Standard. When noise is picked up
as common-mode, it is rejected by the receivers. This
is further enhanced with the 50 Ohm output
impedance of the drivers. The 100 Ohm termination
is integrated into the receivers.
Data integrity is insured with a 5-bit CRC field. CRC
checking is done for both WRITE and READ
operations. An Error (ERR) pin reports the
occurrence of an error. A Write Only mode is also
provided.
The interconnect is reduced from 23 signals to only 4
active signals with the LM4308 chipset easing flex
interconnect design, size constraints and cost.
A low power sleep state entered when the PD* inputs
are driven low.
Small Interface
Low Power
Low EMI
Intrinsic Level Translation
Memory Port (Display) 1.8V
Typical Application Diagram
Apps
Processor
--Graphics
Processor
--Baseband
Processor
CLK
Tree
LM4308
Master
D[17:0]
AD
WR*
RD*
CS2*
CS1*
D[17:0]
AD
WR*
RD*
CS2*
CS1*
DD
(other devices)
DC
ERR
CLK
PLLCON[1:0]
LM4308
Slave
Sub
Display
(Buffered)
Optional
GND
PD*
1.8V
PD*
PWR
2.8V
1.8V
Config.
RDS[1:0]
M/S*
TM
WO
PWR
GND
M/S*
TM
(Bypass Caps
not shown)
Config.
Main
Display
(Buffered)
ERR
PLL
GND
1
2
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of
Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
All trademarks are the property of their respective owners.
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
Copyright © 2007–2013, Texas Instruments Incorporated
LM4308
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Pin Descriptions
Pin Name
No.
of Pads
uArray
Description
No.
of Pins
WQFN
I/O, Type (1)
CPU Master
(MST)
IO, slvs
Differential Data - Positive, Transceiver
CPU Slave
(SLV)
SLVS SERIAL BUS PINS
DDP
1
1
DDN
1
1
IO, slvs
Differential Data - Negative, Transceiver
DCP
1
1
O, I, slvs
Differential Clock - Positive,
Line Driver
Differential Clock - Positive,
Receiver
DCN
1
1
O, I, slvs
Differential Clock - Negative,
Line Driver
Differential Clock - Clock,
Receiver
Low for Slave
CONFIGURATION/PARALLEL BUS PINS
M/S*
1
1
I,
LVCMOS
High for Master
TM
1
1
I,
LVCMOS
Test Mode Control Input
Tie Low
L = Normal
H = Test Mode (factory test only)
PLLCON[1:0]
2
2
I,
LVCMOS
PLL Multiplier Input Pins
See Table 1
NA
RDS[1:0]
2
2
I,
LVCMOS
NA
Receiver Drive Strength Control Input
Pins,
See Table 2
ERR
1
1
O,
LVCMOS
Error Output Signal
Indicates a CRC error on the READ
Payload
Error Output Signal
Reports a CRC error was detected on
the WRITE Payload
WO
1
1
I,
LVCMOS
NA
WRITE Only Control Input
L = Writes and reads enabled
H = Write Only
NA
CLOCK / POWER DOWN SIGNALS
CLK
1
1
I,
LVCMOS
CLK Input
Input is 3.3V Tolerant regardless of
VDDIO
PD*
1
1
I,
LVCMOS
Power Down Input,
L = Powered down, Low Power SLEEP state
H = active state
PARALLEL INTERFACE SIGNALS
D[17:0]
18
18
IO,
LVCMOS
CPU Data Bus Inputs / Outputs
CPU Data Bus Outputs / Inputs
CS1*
CS2*
2
2
I, O,
LVCMOS
Chip Select Input Pins
Only one CS is allowed to be Low at a
time.
Chip Select Output Pins
RD*
1
1
I, O,
LVCMOS
Read Enable Input,
active Low
Read Enable Output,
active Low
WR*
1
1
I, O,
LVCMOS
Write Enable Input,
active Low
Write Enable Output,
active Low
AD
1
1
I, O,
LVCMOS
Address / Data selector input
Address / Data selector output
POWER/GROUND PINS
(1)
2
VDDA
1
1
Power
Power Supply Pin for the PLL (MST) and SLVS Interface. 1.6V to 2.0V
VSSA
1
1
Ground
Ground Pin for the PLL (MST) and SLVS Interface.
VDD
1
1
Power
Power Supply Pin for the digital core. 1.6V to 2.0V
VSS
1
*
Ground
Ground Pin for the digital core.
VDDIO
2
2
Power
Power Supply Pin for the parallel interface I/Os. 1.6V to 3.0V
VSSIO
9
*
Ground
Ground Pin for the parallel interface I/Os.
For the WQFN Package, VSSIO and VSS
Note: I = Input, O = Output, IO = Input/Output. Do not float input pins.
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Pin Descriptions (continued)
Pin Name
No.
of Pads
uArray
No.
of Pins
WQFN
DAP
NA
*
1
Description
I/O, Type (1)
CPU Master
(MST)
CPU Slave
(SLV)
Connect to Ground - WQFN Package
Ground pin for VSSIO and VSS
Table 1. PLLCON[1:0] - PLL Multiplier Settings
PLLCON1
PLLCON0
Multiplier
L
L
8X
L
H
10X
H
L
12X
H
H
Reserved
Table 2. RDS[1:0] - Receiver Output Drive Strength
RDS1
RDS0
Result
L
L
Use with High VDDIO operation
L
H
Increased drive on DATA, AD, and CS1*/CS2* outputs
H
L
Increased drive on WR* and RD*
H
H
All outputs, use for Low VDDIO, Increased drive strength on all outputs
These devices have limited built-in ESD protection. The leads should be shorted together or the device placed in conductive foam
during storage or handling to prevent electrostatic damage to the MOS gates.
ABSOLUTE MAXIMUM RATINGS
(1) (2)
Supply Voltage (VDDA)
−0.3V to +2.2V
Supply Voltage (VDD)
−0.3V to +2.2V
−0.3V to +3.6V
Supply Voltage (VDDIO)
−0.3V to (VDDIO +0.3V)
LVCMOS Input/Output Voltage
−0.3V to +3.3V
CLK LVCMOS Input Voltage
−0.3V to VDDA
SLVS Input/Output Voltage
Junction Temperature
+150°C
Storage Temperature
−65°C to +150°C
ESD Ratings:
≥±2 kV
HBM, 1.5 kΩ, 100 pF
≥±200V
EIAJ, 0Ω, 200 pF
Maximum Package Power Dissipation Capacity at
25°C
NYC Package
2.75 W
Derate NYC Package above 25°C
22 mW/°C
RSB Package
3.43 W
Derate RSB Package above 25°C
(1)
(2)
27 mW/°C
“Absolute Maximum Ratings” are those values beyond which the safety of the device cannot be specified. They are not meant to imply
that the device should be operated at these limits. The tables of “Electrical Characteristics” specify conditions for device operation.
If Military/Aerospace specified devices are required, please contact the TI Sales Office/ Distributors for availability and specifications.
RECOMMENDED OPERATING CONDITIONS
Min
Typ
Max
Units
VDDA to VSSA and VDD to VSS
1.6
1.8
2.0
V
VDDIO to VSSIO
1.6
3.0
V
Clock Frequency
9.6
30
MHz
DC (Serial) Clock Frequency
76.8
240
MHz
Ambient Temperature
−40
85
°C
Supply Voltage
25
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ELECTRICAL CHARACTERISTICS
Over recommended operating supply and temperature ranges unless otherwise specified.
Symbol
Parameter
Conditions
(1) (2)
Min
Typ
Max
Units
140
200
270
mV
-10
0
10
mV
150
200
250
mV
-5
0
5
mV
SLVS
100 Ω Load
VOD
Differential Output Voltage
ΔVOD
Differential Output Voltage
Match
VOS
Driver Offset Voltage
ΔVOS
Driver Offset Voltage Match
ROUT
Driver Output Impedance
VOH
High Level Output Voltage
(Diff. Mode)
RT
Receiver Differential
Termination Resistor
DD (RX) Configuration or DC (SLV)
VIDH
Differential Input High
Threshold
RX, VCM = 35mV, 200mV and 365mV
VIDL
Differential Input Low
Threshold
VCM
Receiver Common Mode Input RX with VID = |70mV|
Range
See
(3)
See
(3)
High Output
50
Low Output
50
Ω
Ω
360
mV
100
125
Ω
10
70
mV
(4)
80
(3)
−70
-10
35
mV
365
mV
V
LVCMOS
VIH
Input Voltage High Level
0.7 VDDIO
VDDIO
VIL
Input Voltage Low Level
GND
0.3 VDDIO
VHY
Input Hysteresis
IIH
Input Current High Level
IIL
Input Current Low Level
VOH
Output Voltage High Level
VOL
Output Voltage Low Level
160
LVCMOS Inputs
VIN = VDDIO
CLK Input
VIN = 3.3V
VDDIO = 1.8V
CLK Input
VIN = 1.8V
VDDIO = 1.8V
−1
(5)
0
0
V
mV
+1
µA
+8
µA
−1
0
+1
µA
−1
0
+1
µA
IOH = −2 mA
RDS = H
VDD = 1.6 V , VDDIO = 2.0 V
0.75 VDDIO
VDDIO
V
IOH = −2 mA
RDS = L
VDD = 2.0 V , VDDIO = 3.0 V
0.8 VDDIO
VDDIO
V
IOL = 2 mA
RDS = H
VDD = 1.6V , VDDIO = 2.0 V
VSSIO
0.2 VDDIO
V
IOL = 2 mA
RDS = L
VDD = 2.0 V , VDDIO = 3.0 V
VSSIO
0.2 VDDIO
V
SUPPLY CURRENT
(1)
(2)
(3)
(4)
(5)
4
Typical values are given for VDDIO = 1.8V and VDD = VDDA = 1.8V and TA = 25°C.
Current into a device pin is defined as positive. Current out of device pins is defined as negative. Voltages are referenced to Ground
unless otherwise specified.
Specification is ensured by characterization and is not tested in production.
Specification is ensured by design and is not tested in production.
When clock input is in overdrive ( Vin = 3.3 V ) and then stop clock is applied, it is recommended to set input clock to a low state.
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ELECTRICAL CHARACTERISTICS (continued)
Over recommended operating supply and temperature ranges unless otherwise specified. (1) (2)
Symbol
IDD
Parameter
Conditions
Total Supply
Current—Enabled
Conditions: CLK = 30MHx (8X
mode), DC = 240MHz,
DD = 480Mbps
Worse Case Data Pattern,
constant WRITE
Master
Supply Current—Enabled
Bus Idle (WR* = H)
Master
Slave
(6)
(6)
Supply Current—Disable
Power Down Modes
PD
Power Dissipation
Max
Units
VDDIO
64
µA
VDD/VDDA
18
mA
VDDIO
18
mA
7
mA
VDDIO
10
µA
VDD/VDDA
8.2
mA
VDDIO
>1
µA
VDD/VDDA
2.9
mA
Master
PD* = L, or CLK stop
VDDIO
8
µA
VDD/VDDA
9
µA
Slave
PD* = L, or Auto
Sleep
VDDIO
8
µA
VDD/VDDA
9
µA
25% Bus active
Master
15
mW
Slave
6
mW
Master
14.8
mW
Slave
5.2
mW
Master
195
µW
Slave
8
µW
Master
>0.1
µW
Slave
>0.1
µW
Idle Bus
QVGA
(7)
PD*=L
(6)
(7)
Typ
VDD/VDDA
Slave
IDDZ
Min
For IDD measurements a checkerboard pattern 2AAAA-15555 was used.
Typical PD for QVGA application. Conditions: 1.8V, 25C, 19.2MHz CLK and 8X, 10% blanking, 1fps. Link is started up, 1 frame (240 x
320) is sent and link is powered down.
SWITCHING CHARACTERISTICS
Over recommended operating supply and temperature ranges unless otherwise specified.
Symbol
Parameter
Conditions
Min
(1)
Typ
Max
Units
PARALLEL BUS TIMING See also Table 5 and Figure 9
tSET
Set Up Time
tHOLD
Hold Time
tRISE
Rise Time
tFALL
Master Input, WRITE
5
ns
5
ns
RD* and WR* Slave VDDIO = 1.6V
Outputs (2)
RDS = H
CL = 15 pF, Figure 2
VDDIO = 3.0V
RDS = L
Fall Time
7
ns
7
ns
VDDIO = 1.6V
RDS = H
7
ns
VDDIO = 3.0V
RDS = L
6
ns
SERIAL BUS TIMING
tDVBC
Data Valid before DC Clock
tDVAC
Data Valid after DC Clock
tSset
Serial Set Time
tShold
Serial Hold Time
tT
Transition Time
(1)
(2)
(3)
(4)
Master
Slave
(3)
(4)
26%
74%
UI
26%
74%
UI
400
ps
400
Master
20% to 80%
ps
200
ps
Typical values are given for VDDIO = 1.8V and VDD = VDDA = 1.8V and TA = 25°C.
Rise and Fall Time tested on the following pins only: WR* and RD*.
Specification is ensured by characterization and is not tested in production.
Specification is ensured by design and is not tested in production.
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SWITCHING CHARACTERISTICS (continued)
Over recommended operating supply and temperature ranges unless otherwise specified. (1)
Symbol
Parameter
Conditions
Min
Typ
Max
Units
POWER UP TIMING
ta
DC ON High Delay
tb
DC Low Delay
tc
DC Active Delay
td
DD High Delay
te
DD Low Delay
tf
DD Differential ON
tSU
Start Up Delay
Includes PLL Lock Time
Link Start Up Sequence
ta +tb + tc + td + te + tf
128
CLK
cycles
128
CLK
cycles
504
CLK
cycles
128
CLK
cycles
8
CLK
cycles
128
CLK
cycles
1,024
CLK
cycles
POWER OFF TIMING
tO
(5)
Turn Off Delay
See
(5)
0.1
2
µs
Typ
Max
Units
30
MHz
104.2
ns
Specified functionally by the IDDZ parameter. See also Figure 7.
RECOMMENDED INPUT TIMING REQUIREMENTS
Over recommended operating supply and temperature ranges unless otherwise specified.
Symbol
Parameter
Conditions
Min
(1)
MASTER REFERENCE CLOCK (CLK)
f
Clock Frequency
9.6
tCP
Clock Period
33.3
CLKDC
Clock Duty Cycle
tT
Clock/Data Transition Times
tCLKgap
CLK Stop Gap
(1)
(2)
6
(Rise or Fall, 10%–90%) (2)
30
50
2
>2
4
70
%
ns
CLKcycles
Typical values are given for VDDIO = 1.8V and VDD = VDDA = 1.8V and TA = 25°C.
Maximum transition time is a function of clock rate and should be less than 30% of the clock period to preserve signal quality.
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TIMING DIAGRAMS
Master
Serial Out
DC
DD
tDVBC tDVAC
50%
tDVBC tDVAC
50%
1UI
Slave
Serial In
DC
DD
tShold
tSset
tShold
tSset
Figure 1. Serial Data Valid & Set/Hold Times
VDDIO
80%
SLV
Outputs
20%
0V
tFALL
tRISE
Figure 2. Slave Output Rise and Fall Time (WR* and RD*)
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FUNCTIONAL DESCRIPTION
BUS OVERVIEW
The LM4308 is a Master (SER) / Slave (DES) configurable part that supports a 18-bit (or less) i80 CPU Display
interface. Both WRITE and READ transactions are supported. The SLVS physical layer is purpose-built for an
extremely low power and low EMI data transmission while requiring the fewest number of signal lines. No
external line components are required, as termination is provided internal to the SLVS receiver. A maximum raw
throughput of 480 Mbps (raw) is possible with this chipset. The SLVS interface is designed for use with 100Ω
differential lines.
LM4308
SLV
LM4308
MST
DD
DC
GND
Figure 3. SLVS Point-to-Point Bus
SERIAL BUS TIMING
Data valid is relative to both edges for a CPU WRITE as shown in Figure 4. Data valid is specified as: Data Valid
before Clock, Data Valid after Clock, and Skew between data lines should be less than 500ps.
DC
(Diff.)
DD
(Diff.)
Figure 4. Serial Link Timing (WRITE)
Data is strobed out on the Rising edge by the Slave for a CPU READ as shown in Figure 5. The Master monitors
for the start bit transition (High to Low) and then selects the best strobe to sample the incoming data on. This is
done to account for the round trip delay of the interconnect and application data rate. Since READ data is sent
on one edge only, the back channel rate (READ) is one quarter that of the WRITE rate.
DC
(Diff.)
DD
(Diff.)
Figure 5. Serial Link Timing (READ)
SERIAL BUS PHASES
There are five bus phases on the serial bus. These are determined by the state of the DC and DD lines. The bus
phases are shown in Table 3.
8
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Table 3. Link Phases (1)
DC State
DD State
OFF (O)
Name
GND
GND
IDLE (I)
A
H
Idle, MD(s) = Logic Low
A or LU
A or O
ACTIVE (A),
Write
A
X
Write Payloads
LU, A, or I
A, I, or O
ACTIVE,
Read
Read Command
A
X
(MST)
Read Command
A, or I
TA’
A
HUH
MD Turn Around
RC
RD
Read Data
A
X
(SLV)
Read Payload
TA’
TA"
TA"
A
HUH
MD Turn Around
RD
I
Master
*
*
O
A, I, or O
LINK-UP
(LU)
(1)
Phase Description
Pre-Phase
Post-Phase
A, I or LU
LU
Link is Off
Start Up
Notes on DC/DD Line State:
0 = no current (off)
SERIAL BUS START UP TIMING
The DC and DD lines are held at a LVCMOS Low state in the Sleep state (PD* = L). When the PD* signal is
switched to a High state the DC lines are pulsed. Next the DC lines are driven to the differential levels and the
clock signal is active. The DD lines are then pulsed from a LVCMOS Low state, then driven to a valid differential
static High state. Data transmission (WRITE) starts with a valid Low start bit on the DD signal.
Bus Phase
Link Off
Link Up
Idle
Active
Idle
Power
H
PD*
L
H
CLK
L
DCP
(SE
Waveform)
DCN
(SE
Waveform)
DC
(DIFF)
DDP
(SE
Waveform)
DDN
(SE
Waveform)
td
ta
DD
(DIFF)
tb
tf
te
tc
tSU
Figure 6. Serial Bus Power Up Timing
Actual start up time is clock rate dependant. The 1024 CLK counter encompasses both the SLVS start up delay
and PLL Lock Time. At 19.2MHz operation, the link is ready for transmission after only 54 µs. Do not WRITE to
either display before the serial link start up delay has expired.
Table 4. Start Up Time vs. CLK Frequency
CLK FREQ
Start Up Delay
9.6MHz
106.7 µs
19.2MHz
53.3 µs
30MHz
34.13 µs
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OFF PHASE
In the OFF phase, differential transmitters are turned off and the lines are both driven to Ground. Figure 7 shows
the transition of the serial bus into the OFF phase. The link may be powered down by asserting Master and
Slave PD* pins, the Master PD* pin alone or stopping the clock . To avoid loss of data the clock input should only
be asserted after the serial bus has been in the IDLE state for at least 100 DC clock cycles. This also applies to
when Master’s PD* input is asserted. The 100 DC clock cycles give the Slave enough time to complete any write
operations received from the serial bus.
Do not asserted the Slave PD* pin alone, as this will not reset the link properly. If the Slave PD* pin is asserted,
the Master’s PD* must also be asserted to generate a proper start up sequence.
Bus Phase
Idle
Active
Link Off
Idle
H
PD*
L
DCP
(SE Waveform)
DCN
(SE Waveform)
DC
(DIFF)
DDP
(SE Waveform)
DDN
(SE Waveform)
DD
(DIFF)
tO
Figure 7. Serial Bus Power Down Timing
I80 CPU INTERFACE COMPATIBILITY
The CPU Interface mode provides compatibility between an i80 CPU Interface and a small form factor (SFF)
Display or other fixed I/O port application. Both WRITE and READ transactions are supported. READs require a
dual access on the Master to complete the operation.
10
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DC
DD
L
AD
R/W* CS12
D15
D16
D0
D17
D1
C0
D2
C1
D3
C2
D4
C3
D5
C4
D6
D7
D8
D9
D10
D11
D12
D13
D14
H
idle
Figure 8. WRITE Transaction
WRITE TRANSACTION
The WRITE transaction consists of 14 DC cycles to send the control, data and CRC information on the DD
signal. This includes the Start Bit, AD, R/W*, CS12, D[0:17], CRC bits C[0:4] and a reserved bit (High). See
Figure 8. The data payload is sent least significant bit (LSB) first. The CS1/2 bit denotes which Chipset pin was
active. CS1/2 = HIGH designates that CS1* is active (Low). CS1/2 = LOW designates that CS2* is active (Low).
CS1* and CS2* Low is not allowed. The AD carries the information on the AD input signal. The R/W* will be Low
for a Write transaction.
Figure 9 illustrates a WRITE transaction showing Master Input, SLVS, and Slave output timing. Table 5 lists the
WRITE timing parameters.
On the Master input, an i80 style WRITE is shown. The ChipSelect (CS1* or CS2*) is Low. The WR* goes Low,
and Data and AD signals are sampled on the rising edge of the WR* signal. A tight set and hold window is
required as shown by T1 and T2. A Latency delay later (T4) the SLVS start bit will be transmitted on the DD
signal. Since it takes 14 DC cycles to send the serial word, a maximum load rate on the Master input should be
slower than this (16 DC cycles or longer). This is T3 in Figure 9.
The Slave output timing is shown in the bottom of Figure 9. Note that the SLV output timing is different than the
MST input timing, however the same information is conveyed. T5 is the latency delay of the Slave and also the
serial payload length. Once the start bit is received, it will take this long for the SLV output to update. First, the
Data[0:17], AD and CS* bits will update as required. One DC cycle later the WRITE signal will transition Low for
12 DC cycles. Then the WRITE signal will transition High and the Display will latch the data. There is a minimum
hold time of one DC cycle (T9). This hold time can (will) be longer as the outputs hold their last state until the
next transition is received. Also note that the CS1* and CS2* signals also hold their last state until they need to
change. This would occur if a transaction is received for the other CS* signal, or if the Slave enters Power Down
(PD*=L).
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DATA[17:0]
AD
T1 T2
MASTER
INPUT
T3
WR*
CS1* or CS2*
other CS*=H
RD*
T4
T5
DC
DD
14
DC
DATA[17:0]
AD
SLAVE
OUTPUT
T6
WR*
T7
RD*
T8
T9
CS1* or CS2*
other CS* = H
Figure 9. WRITE Waveforms
Table 5. i80 CPU WRITE Interface Parameters
No.
12
Parameter
Min
Typ
Max
Units
T1
MasterIN
Data and address Setup Time before Low-High Edge
5
T2
MasterIN
Data and address Hold after Low-High Edge
5
T3
MasterIN
Bus Cycle Rate
16
DC Cycles
T4
Master
Master Latency
7
DC Cycles
T5
Slave
Slave Latency
15
DC Cycles
T6
SlaveOUT
Data Valid before WR* High-Low
1
DC Cycles
T7
SlaveOUT
WR* Low Pulse Width
12
DC Cycles
T8
SlaveOUT
Data Valid before WR* Low-High,
13
DC Cycles
T9
SlaveOUT
Data Valid after WR* Low-High
1
DC Cycles
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READ TRANSACTION
The READ transaction is similar to the WRITE but longer. The full serial READ transaction is shown in
Figure 10 . CRC bits protect both the READ command sent from the Master to the Slave (C[0:4] bits), and also
the Data sent back from the Slave to the Master (RC[0:4] bits). The READ transaction consists of four sections.
In the first section the Master sends a READ Command to the Slave. This command is the same as a WRITE,
but the R/W serial bit is set High and the data payload is ignored. The CRC bits are used to ensure that the
transaction is valid and prevents a false READ from being entered. The Control Input "Write Only - WO" on the
Slave must be set to WRITE & READ mode (Low) to support READ transactions.
In the second section (TA') the DD line is turned around, such that the Master becomes the DD Receiver and
Slave becomes the DD Line Driver. The Slave will drive the DD line High after a fixed number of DC cycles. This
ensures that the DD lines are a stable High state and that the High-to-Low transition of the "Start" bit is seen by
the Master.
The third section consists of the transfer of the read data from the Slave to the Master. Therefore the back
channel data signaling rate is ¼ of the forward channel (Master-to-Slave direction). When the Slave transmits
data back to the Master, it drives the DD line Low to indicate start of read data, followed by the actual read data
and CRC payload.
The fourth and final section (TA") occurs after the read data has been transferred from the Slave to the Master.
In the fourth section the DD line is again turned around, such that the Master becomes the transmitter and the
Slave becomes the receiver. The Slave drives the DD line High for 1 bit and then turns off. The DD lines are OFF
momentarily to avoid driver contention. The Master then drives the DD line High for 1 bit time and then idles the
bus until the next transaction is sent (WRITE or another READ).
DC
A
a r
DD
c
c
c
c
c
c
h
TA'
Read Command
A
B
h
l
l
l
l
RD0
RD1
TA'
RD2
RD3
RD4
RD5
Read Data
B
C
RD6
RD7
RD8
RD9
RD10
RD11
RD12
RD13
RD14
RD15
RD16
RD17
RCRC0
Read Data
C
RCRC1
RCRC2
RCRC3
Read Data
RCRC4
h
TA"
IDLE, Write or
READ
Figure 10. READ Transaction
The READ transaction requires a dual cycle on the Master input to complete. Once the first READ is done
(RDCycle1) the serial link is busy until the second READ (RDCycle2) is done. The Host may do transactions to
other devices between the READs, just not to CS1* or CS2*. On the first READ, the CS1* or CS2* line is driven
low and the RD* pulses low. A fixed Data Word of all Lows is returned and should be ignored by the Host. The
requested data will be available at the Master after 480 DC cycles. The second READ should now be done to
collect the requested data. Upon the READ from the host, the Master will turn ON its 18 data drivers and output
the data to the Host and then turn them off.
When the READ is received, the Data output buffers turn off to avoid contention. After 140 DC cycles the RD*
signal switches Low. It then switches High after another 62 DC cycles and latches in the Data from the Display.
The CRC is then calculated and sent to the Master. To avoid floating the inputs to the Display, the Slave data
outputs are turned back on.
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DATA
LOW
DATA
VALID
DATA[17:0]
AD
T1
T2
T4
MASTER
INPUT
T3
RD*
CS1* or CS2*
other CS*=H
WR*
RDcycle1
RDcycle2
T5a
T5
DC
X
SLV Outputs Update
Data, AD, CS1*, CS2*
as needed
DD
Figure 11. Master Input READ Timing
SLV ON
SLV ON
Display Driver ON
T8
DATA[17:0]
T9
T10
AD
SLAVE
OUTPUT
RD*
T6
T7
WR*
CS1* or CS2*
other CS* = H
Figure 12. Slave Output READ Timing
Table 6. i80 CPU READ Interface Parameters
No.
14
Parameter
Min
Typ
Max
Units
T1
MasterOUT
Data and address valid after RD* High-to-Low
15
ns
T2
MasterOUT
Data and address valid after RD* Low-to-High
T3
MasterIN
Delay Time Between READs
500
0
ns
ns
T4
MasterIN
Delay Time Until Data Available (RDcyc2)
480
ns
T5
Master
Master Latency
7
DC Cycles
T5a
Slave
Slave Latency, (not shown)
158
DC Cycles
T6
Slave
AD Set Time before RD* High-to-Low
140
DC Cycles
T7
Slave
RD* Pulse Low Width
62
DC Cycles
T8
Slave
Data Set Time
7
DC Cycles
T9
Slave
Data Hold Time
0
ns
T10
Slave
Slave Data Outputs
8
DC Cycles
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SLAVE OUTPUT TIMING / DISPLAY COMPATIBILITY
Compatibility of target device’s timing requirements should be checked. Check that the Slave WR* active low
pulse is wide enough for the target display(s). If the Slave output is too fast, a slower DC rate should be chosen
(PLL setting or CLK rate may be adjusted). See SYSTEM CONSIDERATION section also.
Figure 13 illustrates the timing of two writes being sent to CS1*. Note that on the Slave output for Word N, that
the DATA, AD, and CS signals hold their last state until the next transaction is received. This effectively extends
the Hold time after Word N’s WRITE rise. The length of this period (idle) is determined by the time until the next
transaction on the Master input. When the second write is received (Word N+1) the Data, AD, and CS signals
update as needed. Note that the active CS signal stay low until a transaction to the other CS is received or the
Slave is put into powerdown.
MASTER INPUT
Word N to CS1*
Word N+1 to CS1*
DATA[17:0]
AD
RD*
WR*
CS1*
CS2*
SERIAL
DC
DD
L
L
SLAVE OUTPUT
DATA[17:0]
AD
CS1*
CS2*
WR*
RD*
Word N
idle
Word N+1
idle
Figure 13. Timing Example - Two WRITEs to CS1*
CYCLIC REDUNDANCY CHECK (CRC)
The CRC is used to detect errors in both WRITE and READ transactions on the serial link. The LM4308 uses a
5-bit CRC field to detect errors in the 22-bit payload. The Transmitting device calculates the CRC and appends it
to the payload. The Receiver also calculates the CRC and compares it to the received CRC. If they are the
same, the transmission is error free. If they are different, the ERR pin then flags the error.
CRC provides a better coverage than a parity bit, which can only flag one half of the possible errors. The CRC is
calculated by taking the payload and adding 5 zeros and then dividing by a fixed number. The remainder of the
calculation is the 5-bit CRC field that is transmitted.
If a CRC error handling is shown in the table below. See also Figure 14.
Table 7. CRC Error Response
Operation
Direction
Error
Response
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Table 7. CRC Error Response (continued)
Write
Master-to-Slave
CRC error
Slave Flags, ERR pins remains High until
PD* cycle or Power cycle, Data is written to
the display
Read
Command
Master-to-Slave
CRC error
Slave Flags, ERR pins remains High until
PD* cycle or Power cycle, Slave does
nothing
Write
Master-to-Slave,
Slave WO = H
CRC error, Serial R/W* bit
error
(False Read)
Slave Flags, ERR pins remains High until
PD* cycle or Power cycle, Data is written to
the display (write expected)
Read Data
Slave-to-Master
CRC error
Master Flags, ERR goes High, then Low
after 2nd READ, Data = X
Read Data
Slave-to-Master
Read Data not received by
Master
Master times out, drives all Low data, then
on 2nd READ cycle ERR goes High
DATA, AD, CS
(SLV)
ERR
Slave
WRITE
WR*(SLV)
ERR(SLV)
RD*(Host)
ERR
Master
READ
DATA (MST)
ERR(MST)
1 = CS1* active which is a High, and 2 = CS2* active which is a Low
Figure 14. CRC - ERR Output Timing
SLVS INTERFACE
Scalable Low Voltage Signaling is the differential interface used for the physical layer of the serial (Data and
Clock) signals. The differential signal is a 200mV (typ) swing with a 200mV offset from ground. This generates a
±200mV (400mVpp) across the integrated termination resistor for the receiver to recover. The receiver detects
the differential signal and converts it to a LVCMOS signal. Noise picked up along the inteconnect is seen as
common-mode by the receiver and rejected. The low output impedance of the line driver and of the termination
network help to minimize couple noise also.
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mV
P
300
Single-Ended
200
100
N
+200 mV
P-N
0V
Differential
-200 mV
Figure 15. Single-ended and differential SLVS waveforms
Noise that gets coupled onto both signals, is common-mode and is rejected by the receiver. Route the traces that
form the pair together (coupled) to help ensure that noise picked up is common. Differential noise that causes a
dip in the signal but does not enter the threshold region is also rejected. Differntial noise margin is the minimum
VOD signal minus the MAX threshold voltage. 140mV - 70mV = 70mV minimum differential noise margin.
mV
300
P
100
N
Single-Ended
0V
Differential
(P-N)
Figure 16. SLVS common-mode rejection waveform
LM4308 Features and Operation
POWER SUPPLIES
The VDD and VDDA (MPL-2 and PLL) must be connected to the same potential between 1.6V and 2.0V. VDDIO
powers the logic interface and may be powered between 1.6 and 3.0V to be compatible with a wide range of host
and target devices.
BYPASS RECOMMENDATIONS
Bypass capacitors should be placed near the power supply pins of the device. Use high frequency ceramic
(surface mount recommended) 0.1 µF capacitors. A 2.2 to 4.7 µF Tantalum capacitor is recommended near the
Master VDDA pin for PLL bypass. Connect bypass capacitors with wide traces and use dual or larger vias to
reduce resistance and inductance of the feeds. Utilizing a thin spacing between power and ground planes will
provide good high frequency bypass above the frequency range where most typical surface mount capacitors are
less effective. To gain the maximum benefit from this, low inductance feed points are important. Also, adjacent
signal layers can be filled to create additional capacitance. Minimize loops in the ground returns also for
improved signal fidelity and lowest emissions.
MASTER / SLAVE CONFIGURATION
The LM4308 device can be configured to be a Master or a Slave with the M/S* pin. For normal modes, TM (Test
Mode) input must also be Low, setting TM High enters a factory test mode.
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UNUSED/OPEN LVCMOS PINS
Unused inputs must be tied to the proper input level — do not float them. Unused outputs should be left open to
minimize power dissipation.
LVCMOS MASTER INPUT PINS
CPU Interface input pins (Data, AD, CS, WR, RD) accept voltages from -300mV to (VDDIO + 300mV). Inputs are
not High-Z with power supplies OFF. If communication between the Host (i.e. BBP) and other devices (i.e.
Memory) is required when the display is not ON; the power to the Master must be ON, and the Master should be
in SLEEP mode (by CLK Stop or PD*=L). In this condition, Master inputs are High Z and will not load (or clamp)
the shared bus signals. Master inputs are not in a High Z state when Master VDDIO = 0V.
MASTER CLOCK INPUT
The Master Clock input is a special 3.3V Tolerant input pin. This allows the clock tree to be powered from a
different VDDIO than the CPU interface from the host device.
PLLCON1
PLLCON0
Multiplier
0
0
8
CLK Range
9.6 to 30 MHz
0
1
10
9.6 to 24 MHz
1
0
12
9.6 to 20 MHz
1
1
Reserved
Reserved
PHASE-LOCKED LOOP
When the LM4308 is configured as a Master, a PLL is enabled to generate the serial link clock. The Phaselocked loop system generates the serial data clock at several multiples of the input clock. The DC rate is limited
to 240 MHz. The PLL multiplier is set via the PLLCON[1:0] pins. Multipliers of 8X, 10X and 12X are available.
For example, if the input clock is 19.2MHz, and a 8X multiplier is selected, DC will be 153.6 MHz. and the DD
line rate is 307.2 Mbps (raw bandwidth).
POWER DOWN OUTPUT STATES
When the device is in the SLEEP state (PD*=L) the output pins will be driven to the states shown in the table
below.
Device
Signal
State in Power Down
Slave
Data[17:0]
Low
Slave
CS1*, CS2*, WR*, RD*, AD
High
Slave
ERR
Low
Master
ERR
Low
SLAVE
Upon application of power to the SLV device, all outputs are turned on and held in their de-asserted states.
MASTER
Upon application of power to the MST device, the ERR output is ON, and is logic low (normal mode).
SLEEP MODE OPTIONS
The Master can enter sleep mode by three options. The PD* pin is driven low, the clock input is stopped, or if the
power supplies are turned off.
The simplest option is a control signal to drive the PD* input. When PD* input is driven low, the device enters a
sleep mode and supply current is minimized. This mode also supports high-Z Master LVCMOS inputs. The
second option is with Power ON, PD* = H, and the CLK input is stopped. The CLK stop state is recommend to
be logic Low. The Master detects this state and enters the sleep state. The third option is to cut power to the
device. In this configuration the LVCMOS inputs are not High-Z due to internal diodes for ESD protection.
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There are also three options for the Slave to enter the sleep state. These are: based on the MPL-2 interface, the
Slave PD* input pin, and by powering off the Slave device.
With power ON, and the Slave PD* input = H, the Slave detects the state on the MPL-2 bus and powers up or
enters sleep mode. Direct control of the Slave is also possible by the use of its PD* input pin (relative to the
Slave’s VDDIO levels). The third option is to turn off power to the Slave. In this configuration, do not enable and
activate the Master outputs without the Slave also being ON.
SLAVE OUTPUT DRIVE STRENGTH CONTROL
The Slave Outputs have two drive strength options to support a wide range of VDDIO operation. See Table 2. If
the SLV VDDIO is 1.8V TYP, RDS0 and RDS1 should be set to a logic High. Depending upon application speed,
RDS0 can be set to a logic Low to soften the edge rate on the Data signals for less noise. For high VDDIO
operation (i.e. 2.8V), both RDS0 and RDS1 should be set to a logic Low.
SLAVE WRITE ONLY MODE
In some applications, only WRITE operations may be required. In this case, the Slave can be configured to only
support WRITE transactions by setting the WO configuration input High.
Application Information
SYSTEM CONSIDERATIONS
DUAL SMART DISPLAY APPLICATION
A Dual Smart Display application is shown in Figure 17. The Master (MST) resides by the host and connects to a
Memory Interface. VDDIO on the MST is set to be the same as the Host’s port. i80 CPU Bus signals are
connected as shown (Data, AD, WR*, RD*, and CS* signals). The Master also has a SLEEP mode to save
power when the display is not required. The Sleep state is entered when the PD* signal is driven Low. It is also
entered if the PD* signal is High and the CLK input is gated off (held at a static state). In the Sleep state, supply
current into the Master is >1µA typical. In this state, (Power ON, and Sleep state), the Master inputs will not load
the shared bus, and communication between the host and other devices may occur. If power is OFF (VDDIO =
0V), Master input ESD diodes will clamp the bus, preventing communication on the bus. The Master requires a
system clock reference which is typically 19.2MHz in CDMA applications. This signal is used to generate the
serial DC clock. The CLK input is multiplied by the selected PLL multiplier to determine the serial clock rate. In
the 19.2MHz CLK and 8X application, the DC rate will be 153.6MHz. Due to the serial transmission scheme
using both clock edges, the raw bandwidth of a WRITE is 307.3 Mbps. The Master also provides a ERR pin that
reports a CRC error on a READ transaction. The host may monitor this signal if desired, or it may be brought out
to a test point only. Several configuration pins are also required to be set. For a Master, tie M/S* = H, TM = L,
and PLLCON[1:0] to the desired setting.
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LM4308 (Master)
E1
E2
F1
F2
G1
G2
F3
G3
G5
F5
G6
F6
G7
F7
E6
E7
D6
C7
BaseBand
Processor
VDD
D0
D1
D2
D3
D4
D5
D6
D7
D8
D9
D10
D11
D12
D13
D14
D15
D16
D17
C1
A1
D2
C2
A2
WR*
A/D
RD*
CS2
CS1
A3
PD*
VDDA
VDDIO
DDP_M
DDN_M
DCP_M
DCN_M
ERR
VSS
VSSA
VSSI/O
VSSI/O
VSSI/O
VSSI/O
VSSI/O
VSSI/O
VSSI/O
VSSI/O
VSSI/O
1.8V
CLK
Tree
B1
B7
B6
B2
MS*
CLK
PCON1
PCON0
TM
Notes:
1. PCON1, PCON0 = Low = x 8 Mode
2. Bypass Capacitor Values :
C1, C2 = 4.7 PF
C3 = 2.2 PF
C4 = 0.1 PF
B5
C3
D7
D1
C4
C3
A7
A6
A4
A5
C6
F4
B4
C3
C4
C5
D3
D4
D5
E3
E4
E5
VDDA
C2
D7
D1
VDD
C1
B5
C2
VDDIO
LM4308 (Slave)
1.8V
G4
C1
(Other Devices)
B3
1.8V
G4
A4
A5
A7
A6
F4
B4
C3
C4
C5
D3
D4
D5
E3
E4
E5
VDDIO
VDDIO
DDP_S
DDN_S
DCP_S
DCN_S
VSS
VSSA
VSSI/O
VSSI/O
VSSI/O
VSSI/O
VSSI/O
VSSI/O
VSSI/O
VSSI/O
VSSI/O
D0
D1
D2
D3
D4
D5
D6
D7
D8
D9
D10
D11
D12
D13
D14
D15
D16
D17
WR*
A/D
RD*
CS1
CS2
E1
E2
F1
F2
G1
G2
F3
G3
G5
F5
G6
F6
G7
F7
E6
E7
D6
C7
Main
Display
(Buffered)
C1
A1
D2
A2
C2
Sub Display
(Buffered)
Optional
1.8V
RDS0
RDS1
WO
ERR
PD*
TM
MS*
B6
B7
B1
C6
A3
B2
B3
Notes:
1. RDS0 and RDS1 are VDDIO dependent. If/When VDDIO = 3.0V, RDS0
and RDS1 should be strapped low.
2.Bypass Capacitor Values :
C1,C2 = 4.7 PF
C3 = 0.1 PF
Figure 17. Dual SMART Display Application
The Slave recovers the serial signals and generates the parallel bus for the Display(s). The Slave VDDIO is set to
be compatible with the Displays employed. The Data bus signals are bidirectional to support both WRITEs and
READs. The other signals. AD, WR*, RD*, and CS* signals are outputs only. The connection between the Slave
device and the displays should be done such that long stubs are avoided. Extra care should be taken on the
WR* and RD* signal layouts as these signals rely on the signal edges to latch the data. The Slave has user
adjustable edge rate controls for the parallel bus outputs. This can be used to optimize the edge rate vs the
required VDDIO magnitude. Also, independent control of the strobe (WR* and RD*) is supported. This allows for
the strobe signal to retain sharp edges, while using softer edges on the wide parallel data bus signals. This aids
in noise reduction. The Slave also provides a ERR pin to flag any CRC errors detected. This signal maybe routed
back to the host for monitoring, or bought out to a test point. The Slave supports a WRITE ONLY mode (READ
operation and serial bus turn around is prevented). This mode is obtained by setting the WO pin to a logic High.
The Sleep state of the display may be entered by driving the PD* signal to a logic Low. Outputs are then set to
their Power Down de-asserted states. Several configuration pins are also required to be set. For a Slave, tie
M/S* = L, TM = L, and WO and RDS[1:0] to the desired setting. If only one display is required in the application,
the unused CS output signal should be left un-connected.
In this application, WRITEs and READs for the Displays are serialized and sent to the displays. Transaction to
other devices on the shared bus (MST input) are ignored by the Master.
SYSTEM TIMING CONSIDERATIONS
When employing the SERDES chipset in place of a parallel bus, a few system considerations must be taken into
account. Before sending commands (i.e. initialization commands) to the display, the SERDES must be ready to
transmit data across the link. The serial link must be powered up, and the PLL must be locked. Also, a review of
the Slave output timing should be completed to insure that the timing parameters provided by the Slave output
meet the requirements of the LCD driver input. Specifically, pulse width on WR* and RD*, data valid time, and
bus cycle rate should be reviewed and checked for display compatibility. Additional details are provided next:
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The serial link should be started up as follows: The chipset should be powered. During power up, the PD* inputs
should be held Low and released once power is stable and within specification and link transmission is desired.
Before data can be sent across the serial link, the link must be ready for transmission. The CLK needs to be
applied to the MST, and the PLL locked. This is controlled by a keep-off counter set for 1024 CLK cycles. After
the PLL has locked and the counter expired, transmission may now occur. For a 19.2MHz application is is less
than 54µs delay. If a WRITE is done to the display during this time, it will be lost and the display may not be
properly configured. Ensure that the FIRST WRITE to the display is done AFTER the link is ready for
transmission.
It takes 14 DC Cycles to send a 18-bit CPU Write including the serial overhead. The DC cycle time is calculated
based on the PLL Multiplier setting and also the input clock frequency. For example, a 19.2 MHz input CLK and
a 8X PLLCON[1:0] setting yields a DC frequency of 153.6 MHz. Thus it takes ∼100 ns to send the word in serial
form. To allow some idle time between transmissions (this will force a bit sync per word if the gap is long enough
in between), the load rate on the Master input should not be faster than 16 DC cycles, or every 105 ns (9.6 MT/s)
in our example to support a data pipe line. This is sometimes referred to as the bus cycle time (time between
commands). Thus the time between WRITEs on the Master Input MUST NOT be faster than 105 ns, otherwise
the FIFO will overflow and data will be lost.
The Slave output WR* and RD* timing is a function of DC cycles alone. The width of the WR* pulse low is
TWELVE DC cycles regardless of the pulse width applied to the Master input. In the 19.2MHz & 8X application,
the WR* pulse low will be 78 ns. System designers need to check compatibility with the display driver to ensure
that this pulse width meets its requirement. If it is too fast, select a lower PLL Multiplier or apply a slower input
clock.
PCB LAYOUT – SERIAL SIGNALS
The LM4308 provides a swap function of SLVS DD and DC lines depending upon the state of the M/S* pin. This
facilitates a straight through via-less SLVS interface design eliminating the needs for via and crossovers as
shown on Figure 18. It is recommended to use separate logic symbols for the Master and the Slave to avoid
layout errors.
NOTE
THE PINOUT IS DIFFERENT FOR A MASTER AND SLAVE CONFIGURED DEVICE.
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PD*
CS1*
AD
MASTER
CLK
CS2*
WR*
RD*
SLAVE
D0
ERR
D1
D17
D2
A
D3
D16
1
D4
D15
TOP VIEW
D14
D5
D13
D6
D12
D7
D8
D11
7
DC
D10
D9
D9
D10
D8
DD
D11
D7
D12
D6
D13
7
D5
D4
D14
D15
D3
D16
D2
1
D17
ERR
D1
A
D0
WR*
CS2*
Notes:
Static and Supply signals not shown.
Inner row may also use via in escape.
AD
CS1*
PD*
Figure 18. SLVS Interface Layout
FLEX CIRCUIT RECOMMENDATIONS
A differential 100 Ohm transmission path will yield the best results and be matched to the integrated differential
termination resistance. Also, the interconnect should employ a coupled lines to ensure that the majority of any
noise pick up is common-(equal on both the P and N signals) so that it is rejected by the differential receiver. A
GSSGSSG pinout is recommended. Depending on external noise sources, shielding maybe required.
GROUNDING
Even though the serial Data and Clock signals are differential, a common ground signal is still required. This
provides a common ground reference between the devices and a current return path for the common mode
current.
GENERAL GUIDELINES and RECOMMENDATIONS FOR PCB DESIGN
LVCOMS Signals:
• To reduce EMI, avoid parallel runs with fast edge, large LVCMOS swings.
• To reduce crosstalk allow enough space between traces. It is recommended to distance the centers of two
adjacent traces at least four times the trace width. To improve design performance, lower the distance
between the trace and the ground plane to under ~ 10 mils.
• Keep clock trace as straight as possible. Use arc-shaped traces as an alternative to the right-angle bends.
• Do not use multiple signal layers for clock signals.
• Do not use vias in clock transmission lines, as vias can cause impedance change and reflection.
SLVS Signals:
• Floor plan, locate Master near the connector to limit chance of cross talk to high speed serial signals.
• Use differential routing techniques. (i.e., match the lengths as well as the turns that each trace goes through)
• Keep the length of the two differential traces the same to minimize the skew and phase difference.
• Route serial traces together, minimize the number of layer changes to reduce loading.
22
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•
•
•
•
•
•
•
SNLS225C – AUGUST 2007 – REVISED MAY 2013
Use ground lines are guards to minimize any noise coupling (specifies distance).
Avoid using multiple vias to reduce impedance mismatch and inductance.
Use a GSSGSSG pinout in connectors (Board to Board or ZIF).
Bypass the device with MLC surface mount devices and thinly separated power and ground planes with low
inductance feeds.
High current returns should have a separate path with a width proportional to the amount of current carried to
minimize any resulting IR effects.
Slave device - follow similar guidelines.
see AN-1126 (SNOA021) (BGA) and AN-1187 (SNOA401) (WQFN) also
Connection Diagram csBGA Package
Ball A1
A
B
C
D
E
F
G
1
2
3
4
5
6
7
Figure 19. TOP VIEW
(not to scale)
Note that the pinout of a MASTER configured device is DIFFERENT than a SLAVE configured device. The use
of two logic symbols for PCB schematic is recommended.
Table 8. CPU Master Pinout
MST
1
2
3
4
5
6
7
A
AD
CS1*
PD*
DCP_M
DCN_M
DDN_M
DDP_M
B
CLK
TM
M/S*
VSSA
VDDA
PLLCON0
PLLCON1
C
WR*
CS2*
VSSIO
VSSIO
VSSIO
ERR
D17
D
VDDIO
RD*
VSSIO
VSSIO
VSSIO
D16
VDDIO
E
D0
D1
VSSIO
VSSIO
VSSIO
D14
D15
F
D2
D3
D6
VSS
D9
D11
D13
G
D4
D5
D7
VDD
D8
D10
D12
Table 9. CPU Slave Pinout
SLV
1
2
3
4
5
6
7
A
AD
CS1*
PD*
DDP_S
DDN_S
DCN_S
DCP_S
RDS1
B
WO
TM
M/S*
VSSA
VDDA
RDS0
C
WR*
CS2*
VSSIO
VSSIO
VSSIO
ERR
D17
D
VDDIO
RD*
VSSIO
VSSIO
VSSIO
D16
VDDIO
E
D0
D1
VSSIO
VSSIO
VSSIO
D14
D15
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SNLS225C – AUGUST 2007 – REVISED MAY 2013
www.ti.com
Table 9. CPU Slave Pinout (continued)
SLV
1
2
3
4
5
6
7
F
D2
D3
D6
VSS
D9
D11
D13
G
D4
D5
D7
VDD
D8
D10
D12
VDDIO
RD*
WR*
CS2*
WO
AD
5
4
3
2
1
AD
1
6
CLK
2
D0
CS2*
3
7
WR*
4
D1
RD*
5
8
VDDIO
6
D2
D0
7
9
D1
8
D3
D2
9
10
D3
10
Connection Diagram - WQFN Package
D4
11
40
TM
D4
11
40
TM
D5
12
39
CS1*
D5
12
39
CS1*
D6
13
38
M/S*
D6
13
38
M/S*
D7
14
37
PD*
D7
14
PD*
15
36
DCP
NC
15
36
DDP
VDD
16
35
VSSA
VDD
16
TOP VIEW
40 Lead WQFN
5mm x 5mm x 0.8mm
0.4mm pitch
(not to scale)
37
NC
TOP VIEW
40 Lead WQFN
5mm x 5mm x 0.8mm
0.4mm pitch
(not to scale)
35
VSSA
D8
17
M/S*=H, MASTER
34
DCN
D8
17
M/S*=L, SLAVE
34
DDN
D9
18
(DAP connection, center pad = GND)
33
VDDA
D9
18
(DAP connection, center pad = GND)
33
VDDA
D10
19
32
DDN
D10
19
32
DCN
D11
20
31
DDP
D11
20
31
DCP
30
29
RDS1
RDS0
28
27
D17
ERR
26
24
D15
VDDIO
23
D14
25
22
D13
D16
21
LM4308SQ
D12
27
D17
30
26
VDDIO
PLLCON0
25
D16
29
24
D15
PLLCON1
23
D14
28
22
D13
ERR
21
D12
LM4308SQ
Figure 20. TOP VIEW — (not to scale)
Note that the pinout of a MASTER configured device is DIFFERENT than a SLAVE configured device. The use
of two logic symbols for PCB schematic is recommended.
Table 10. CPU Master - Slave Pad Assignments
Pin #
Master
1
2
24
Slave
AD
CLK
WO
Pad #
Master
Slave
21
D12
22
D13
3
CS2*
23
D14
4
WR*
24
D15
5
RD*
25
D16
6
VDDIO
26
VDDIO
7
D0
27
D17
8
D1
28
ERR
9
D2
29
PLLCON1
10
D3
30
PLLCON0
RDS0
11
D4
31
DDP_M
DCP_S
12
D5
32
DDN_M
13
D6
33
14
D7
34
15
NC
35
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RDS1
DCN_S
VDDA
DCN_M
DDN_S
VSSA
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SNLS225C – AUGUST 2007 – REVISED MAY 2013
Table 10. CPU Master - Slave Pad Assignments (continued)
Pin #
Pad #
Master
Slave
16
Master
VDD
Slave
36
DCP_M
DDP_S
17
D8
37
PD*
18
D9
38
M/S*
19
D10
39
CS1*
20
D11
40
TM
DAP
VSSIO / VSS
DAP
VSSIO / VSS
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LM4308
SNLS225C – AUGUST 2007 – REVISED MAY 2013
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REVISION HISTORY
Changes from Revision B (May 2013) to Revision C
•
26
Page
Changed layout of National Data Sheet to TI format .......................................................................................................... 25
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PACKAGE OPTION ADDENDUM
www.ti.com
2-May-2013
PACKAGING INFORMATION
Orderable Device
Status
(1)
Package Type Package Pins Package
Drawing
Qty
Eco Plan
Lead/Ball Finish
(2)
MSL Peak Temp
Op Temp (°C)
Top-Side Markings
(3)
(4)
LM4308GR/NOPB
ACTIVE
csBGA
NYC
49
1000
Green (RoHS
& no Sb/Br)
CU SNAGCU
Level-1-260C-UNLIM
L4308GR
LM4308GRX/NOPB
ACTIVE
csBGA
NYC
49
3500
Green (RoHS
& no Sb/Br)
CU SNAGCU
Level-1-260C-UNLIM
L4308GR
LM4308SQ/NOPB
ACTIVE
WQFN
RSB
40
1000
Green (RoHS
& no Sb/Br)
SN
Level-3-260C-168 HR
L4308SQ
LM4308SQX/NOPB
ACTIVE
WQFN
RSB
40
4500
Green (RoHS
& no Sb/Br)
SN
Level-3-260C-168 HR
L4308SQ
(1)
The marketing status values are defined as follows:
ACTIVE: Product device recommended for new designs.
LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect.
NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design.
PREVIEW: Device has been announced but is not in production. Samples may or may not be available.
OBSOLETE: TI has discontinued the production of the device.
(2)
Eco Plan - The planned eco-friendly classification: Pb-Free (RoHS), Pb-Free (RoHS Exempt), or Green (RoHS & no Sb/Br) - please check http://www.ti.com/productcontent for the latest availability
information and additional product content details.
TBD: The Pb-Free/Green conversion plan has not been defined.
Pb-Free (RoHS): TI's terms "Lead-Free" or "Pb-Free" mean semiconductor products that are compatible with the current RoHS requirements for all 6 substances, including the requirement that
lead not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, TI Pb-Free products are suitable for use in specified lead-free processes.
Pb-Free (RoHS Exempt): This component has a RoHS exemption for either 1) lead-based flip-chip solder bumps used between the die and package, or 2) lead-based die adhesive used between
the die and leadframe. The component is otherwise considered Pb-Free (RoHS compatible) as defined above.
Green (RoHS & no Sb/Br): TI defines "Green" to mean Pb-Free (RoHS compatible), and free of Bromine (Br) and Antimony (Sb) based flame retardants (Br or Sb do not exceed 0.1% by weight
in homogeneous material)
(3)
MSL, Peak Temp. -- The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder temperature.
(4)
Multiple Top-Side Markings will be inside parentheses. Only one Top-Side Marking contained in parentheses and separated by a "~" will appear on a device. If a line is indented then it is a
continuation of the previous line and the two combined represent the entire Top-Side Marking for that device.
Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is provided. TI bases its knowledge and belief on information
provided by third parties, and makes no representation or warranty as to the accuracy of such information. Efforts are underway to better integrate information from third parties. TI has taken and
continues to take reasonable steps to provide representative and accurate information but may not have conducted destructive testing or chemical analysis on incoming materials and chemicals.
TI and TI suppliers consider certain information to be proprietary, and thus CAS numbers and other limited information may not be available for release.
In no event shall TI's liability arising out of such information exceed the total purchase price of the TI part(s) at issue in this document sold by TI to Customer on an annual basis.
Addendum-Page 1
Samples
PACKAGE OPTION ADDENDUM
www.ti.com
2-May-2013
Addendum-Page 2
PACKAGE MATERIALS INFORMATION
www.ti.com
8-May-2013
TAPE AND REEL INFORMATION
*All dimensions are nominal
Device
Package Package Pins
Type Drawing
SPQ
Reel
Reel
A0
Diameter Width (mm)
(mm) W1 (mm)
B0
(mm)
K0
(mm)
P1
(mm)
W
Pin1
(mm) Quadrant
LM4308GR/NOPB
csBGA
NYC
49
1000
178.0
12.4
4.3
4.3
1.5
8.0
12.0
Q1
LM4308GRX/NOPB
csBGA
NYC
49
3500
330.0
12.4
4.3
4.3
1.5
8.0
12.0
Q1
LM4308SQ/NOPB
WQFN
RSB
40
1000
178.0
12.4
5.3
5.3
1.3
8.0
12.0
Q1
LM4308SQX/NOPB
WQFN
RSB
40
4500
330.0
12.4
5.3
5.3
1.3
8.0
12.0
Q1
Pack Materials-Page 1
PACKAGE MATERIALS INFORMATION
www.ti.com
8-May-2013
*All dimensions are nominal
Device
Package Type
Package Drawing
Pins
SPQ
Length (mm)
Width (mm)
Height (mm)
LM4308GR/NOPB
csBGA
NYC
49
1000
210.0
185.0
35.0
LM4308GRX/NOPB
csBGA
NYC
49
3500
367.0
367.0
35.0
LM4308SQ/NOPB
WQFN
RSB
40
1000
213.0
191.0
55.0
LM4308SQX/NOPB
WQFN
RSB
40
4500
367.0
367.0
35.0
Pack Materials-Page 2
MECHANICAL DATA
NYC0049A
GRA49A (Rev A)
www.ti.com
MECHANICAL DATA
RSB0040A
SQF40A (Rev B)
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