mc33996ek/r2 Freescale Semiconductor, Inc, mc33996ek/r2 Datasheet - Page 13

• Manufacturer Part Number: mc33996ek/r2
• Description: 16-output Switch With Spi Control
• Manufacturer: Freescale Semiconductor, Inc

outputs. The device allows PWM and ON /OFF control
through the use of several 24-bit input command words. This
section describes the logic operation and command registers
of the 33996.
shown in
ON/OFF CONTROL REGISTER
24-bit serial stream of data is entered into the SI pin. The first
8 bits of the control word are used to identify the on/off
command and the remaining 16 bits are used to turn ON or
OFF the specific output driver.
OPEN LOAD CURRENT ENABLE CONTROL
REGISTER
provided to enable or disable the 50 µA open load detect pull-
down current. This feature allows the device to be used in
LED applications. Power-ON Reset (POR) or the
the RESET command disables the 50 µA pull-down current.
No open load fault will be reported with the pull-down current
disabled. For open load to be active, the user must program
the Open Load Current Enable Control register with logic [1].
GLOBAL SHUTDOWN/RETRY CONTROL
REGISTER
user to select the global fault strategy for the outputs. The
over-voltage control bit (bit 16) sets the operation of the
Analog Integrated Circuit Device Data
Freescale Semiconductor
Table 6. SPI Control Commands
ON/OFF Control
0 = off, 1 = on
Open Load Current Enable
0 = disable, 1 = enable
Global Shutdown/Retry
Control
0 = shutdown, 1 = retry
SFPD Control
1 = therm only, 0 = V
PWM Enable
0 = SPI only, 1 = PWM
AND/OR Control
0 = PWM pin AND with SPI
1 = PWM pin OR with SPI
Reset
SO Response
0 = No Fault, 1 = Fault
The 33996 provides flexible control of 16 low-side driver
The 33996 message set consists of seven messages as
To program the 16 outputs of the 33996 ON or OFF, a
The Open Load Current Enable Control register is
The Global Shutdown/Retry Control register allows the
Commands
Table
DS
6. Bits 23 through18 determine the specific
MSB
Fault
Any
23
0
0
0
0
0
0
0
over-
volt-
age
22
0
0
0
0
0
0
0
21
0
0
0
0
0
0
0
0
20
0
0
0
0
1
1
1
0
LOGIC COMMANDS AND REGISTERS
19
0
0
1
1
0
0
1
0
18
0
1
0
1
0
1
0
0
Thermal
Bit 0
17
X
X
X
X
X
X
0
RST
voltage
INTRODUCTION
Over-
pin or
16
X
X
0
X
X
X
X
0
OUT
15
15
0
0
X
1
0
0
X
OUT
14
14
X
X
0
0
1
0
0
command and bits 15 through 0 determine how a specific
output will operate. The 33996 operates on the command
word on the rising edge of
in
outputs when returning from over-voltage. Setting the over-
voltage bit to logic [0] will force all outputs to remain off when
V
logic [1] will command outputs to resume their previous state
when V
thermal bit. When bit 17 is set to logic [0], all outputs will shut
down when thermal limit is reached and remain off even after
cooled. With bit 17 set to logic [1], all outputs will shut down
when thermal limit is reached and will retry when cooled.
SHORT FAULT PROTECT DISABLE (SFPD)
CONTROL REGISTER
programmable retry. The SFPD control bits are used for fast
shutdown of the output when overcurrent condition is
detected but thermal shutdown has not been achieved.
specific outputs for incandescent lamp loads and specific
outputs for inductive loads. By programming the specific
SFPD bit as logic [1], output will rely on over temperature
shutdown only. Programming the specific SFPD bit as
logic [0] will shut down the output after 100 µs to 450 µs
during turn on into short circuit. The decision for shutdown is
PWR
OUT
Table
13
13
Note Upon Power-ON Reset all bits are defined as shown
X
X
All outputs contain current limit and thermal shutdown with
The SFPD Control register allows the user to select
0
0
1
0
0
Bits
OUT
returns to normal level. Setting the over-voltage bit to
12
12
0
0
X
1
0
0
X
PWR
6.
OUT
11
11
X
X
0
0
1
0
0
returns to normal level. Bit 17 is the global
OUT
10
10
X
X
0
0
1
0
0
OUT
9
0
0
X
1
0
0
X
9
OUT
LOGIC COMMANDS AND REGISTERS
X
X
8
0
0
1
0
0
8
CS
OUT
X
X
7
0
0
1
0
0
7
.
OUT
6
0
0
X
1
0
0
X
6
OUT
X
X
5
0
0
1
0
0
5
OUT
4
0
0
X
1
0
0
X
4
INTRODUCTION
OUT
3
0
0
X
1
0
0
X
3
OUT
X
X
2
0
0
1
0
0
2
OUT
1
0
0
X
1
0
0
X
1
33996
OUT
LSB
13
X
X
0
0
0
1
0
0
0