TLE8104E Datasheet, PDF (16/27 Pages) Infineon Technologies AG – Smart Quad Channel Powertrain Switch

TLE8104E
Smart Quad Channel Powertrain Switch
Electrical and Functional Description of Blocks
5.5.2 Daisy Chain Capability
The SPI of TLE8104E is daisy chain capable. In this configuration several devices are activated by the same signal
CS. The SI line of one device is connected with the SO line of another device (see Figure 11), which builds a
chain. The ends of the chain are connected with the output and input of the master device, SO and SI respectively.
The master device provides the master clock SCLK, which is connected to the SCLK line of each device in the
chain.
device 1
device 2
device 3
SI
SO SI
SO SI
SO
SO
SPI
SPI
SPI
SI
CS
SCLK
Figure 11 Daisy Chain Configuration
In the SPI block of each device, there is one shift register where one bit from SI line is shifted in each SCLK. The
bit shifted out can be seen at SO. After 8 SCLK cycles, the data transfer for one device has been finished. In single
chip configuration, the CS line must go high to make the device accept the transferred data. In daisy chain
configuration the data shifted out at device 1 has been shifted in to device 2. When using three TLE8104E devices
in daisy chain, three times 8 bits have to be shifted through the devices. After that, the CS line must go high (see
Figure 12).
SI SO device 3
SO device 2
SO SI device 3
SI device 2
CS
CLK
time
Figure 12 Data Transfer in Daisy Chain Configuration
SO device 1
SI device 1
Electrical Characteristics: SPI Interface
V_S = 4.5 V to 5.5 V, T_j = -40 °C to +150 °C, (unless otherwise specified)
all voltages with respect to ground, positive current flowing into pin
Pos. Parameter
Symbol
Limit Values
Min. Typ. Max.
5.5.1 Input Pull-down Current (SI, SCLK) I_IN(SI,SCLK) 10
20
50
5.5.2 Input Pull-up Current (CS)
I_IN(CS)
-50
-20
-10
5.5.3 SO High State Output Voltage
V_SO(H)
V_S - 0.4 –
–
5.5.4 SO Low State Output Voltage
V_SO(L)
–
–
0.4
5.5.5 Serial Clock Frequency
(depending on SO load)
f_SCLK
DC
–
5
Unit Conditions
µA
µA
V
V
MHz
V_SI,SCLK = V_S
V_CS = 0 V
I_SOH = 2 mA
I_SOL = -2.5 mA
–
Data Sheet
16
V1.4, 2010-04-26