Freescale Semiconductor
Advance Information
Document Number: MC33984
Rev. 16.0, 9/2014
Dual Intelligent High-current
Self-protected Silicon High-side
Switch (4.0 mOhm
33984
The 33984 is a dual self-protected 4.0 mOhm silicon switch used to replace
electromechanical relays, fuses, and discrete devices in power management
applications. The 33984 is designed for harsh environments, and it includes
self-recovery features. The device is suitable for loads with high inrush current,
as well as motors and all types of resistive and inductive loads.
Programming, control, and diagnostics are implemented via the serial
peripheral interface (SPI). A dedicated parallel input is available for alternate
and pulse-width modulation (PWM) control of each output. SPI-programmable
fault trip thresholds allow the device to be adjusted for optimal performance in
the application.
The 33984 is packaged in a power-enhanced 12 mm x 12 mm nonleaded
PQFN package with exposed tabs.
HIGH-SIDE SWITCH
BOTTOM VIEW
FK SUFFIX
98ARL10521D
16-PIN PQFN
Features
•
•
•
•
Dual 4.0 m max. high-side switch with parallel input or SPI control
6.0 V to 27 V operating voltage with standby currents < 5.0 A
Output current monitoring with two SPI-selectable current ratios
SPI control of overcurrent limit, overcurrent fault blanking time, output OFF
open load detection, output ON/OFF control, watchdog timeout, slew-rates,
and fault status reporting
• SPI status reporting of overcurrent, open and shorted loads,
overtemperature, undervoltage and overvoltage shutdown, fail-safe pin
status, and program status
• Enhanced -16 V reverse polarity VPWR protection
VDD
VDD
VDD
Applications
• DC motor or solenoid
• Resistive or inductive loads
• Low-voltage lighting
VPWR
33984
VDD
I/O
FS
I/O
WAKE
SO
SI
SCLK
MCU
GND
HS1
SCLK
CS
CS
SI
SO
I/O
RST
I/O
INO
I/O
IN1
A/D
VPWR
HS0
LOAD
LOAD
CSNS
FSI
GND
Figure 1. 33984 Simplified Application Diagram
* This document contains certain information on a new product.
Specifications and information herein are subject to change without notice.
© Freescale Semiconductor, Inc., 2007-2014. All rights reserved.
ORDERABLE PARTS
ORDERABLE PARTS
Table 1. Orderable Part Variations (1)
Part Number
Temperature (TA)
Package
Output Clamp
Energy
Reference
Location
OD3 bit for X111
address
Reference
Location
MC33984CHFK
-40 °C to 125 °C
16 PQFN
0.5J
Table 4
1
Table 17
Notes
1. To order parts in Tape & Reel, add the R2 suffix to the part number.
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Analog Integrated Circuit Device Data
Freescale Semiconductor
INTERNAL BLOCK DIAGRAM
INTERNAL BLOCK DIAGRAM
VPWR
VDD
Internal
Regulator
IUP
VIC
Overvoltage
Protection
CS
Programmable
Switch Delay
0 ms to 525 ms
SO
SPI
3.0 MHz
Selectable Slew
Rate Gate Drive
HS0
Selectable Overcurrent
High Detection
100 A or 75 A
SI
SCLK
FS
IN[0:1]
RST
WAKE
Logic
Selectable Over
current Low Detection
Blanking Time
0.15 ms to155 ms
Selectable Overcurrent
Low Detection
7.5 A to 25 A
Open Load
Detection
IDWN
Overtemperature
Detection
RDWN
HS0
HS1
Programmable
Watchdog
310 ms to 2500 ms
HS1
VIC
IUP
Selectable
Output Current
Recopy
1/20500 or 1/41000
FSI
GND
CSNS
Figure 2. 33984 Simplified Internal Block Diagram
33984
Analog Integrated Circuit Device Data
Freescale Semiconductor
3
PIN CONNECTIONS
PIN CONNECTIONS
4
3 2
CSNS
RST
WAKE
6 5
FS
7
IN0
CS
FSI
SI
SCLK
SO
VDD
IN1
12 11 10 9 8
1
13
GND
TRANSPARENT
TOP VIEW
14
VPWR
15
HS1
16
HS0
Figure 3. 33984 Pin Connections (Transparent Top View)
Functional descriptions of many of these pins can be found in the Functional Pin Description section beginning on page 16.
Table 2. Pin Definitions
Pin
Pin Name
Pin
Function
Formal Name
Definition
1
CSNS
Output
Output Current Monitoring
This pin is used to output a current proportional to the designated HS0-1 output.
2
WAKE
Input
Wake
3
RST
Input
Reset (Active Low)
4
IN0
Input
Direct Input 0
5
FS
Output
Fault Status (Active Low)
This is an open drain configured output requiring an external pull-up resistor to
VDD for fault reporting.
6
FSI
Input
Fail-safe Input
The value of the resistance connected between this pin and ground determines
the state of the outputs after a watchdog timeout occurs.
7
CS
Input
Chip Select (Active Low)
8
SCLK
Input
Serial Clock
This input pin is connected to the MCU providing the required bit shift clock for
SPI communication.
9
SI
Input
Serial Input
This is a command data input pin connected to the SPI serial data output of the
MCU or to the SO pin of the previous device of a daisy chain of devices.
10
VDD
Input
Digital Drain Voltage
(Power)
11
SO
Output
Serial Output
This output pin is connected to the SPI serial data input pin of the MCU or to the
SI pin of the next device of a daisy chain of devices.
12
IN1
Input
Direct Input 1
This input pin is used to directly control the output HS1.
13
GND
Ground
Ground
This pin is used to input a logic [1] signal so as to enable the watchdog timer
function.
This input pin is used to initialize the device configuration and fault registers, as
well as place the device in a low current Sleep mode.
This input pin is used to directly control the output HS0.
This input pin is connected to a chip select output of a master microcontroller
(MCU).
This is an external voltage input pin used to supply power to the SPI circuit.
This pin is the ground for the logic and analog circuitry of the device.
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Analog Integrated Circuit Device Data
Freescale Semiconductor
PIN CONNECTIONS
Table 2. Pin Definitions (continued)
Pin
Pin Name
Pin
Function
Formal Name
14
VPWR
Input
Positive Power Supply
15
HS1
Output
High-side Output 1
Protected 4.0 m high-side power output to the load.
16
HS0
Output
High-side Output 0
Protected 4.0 m high-side power output to the load.
Definition
This pin connects to the positive power supply and is the source input of
operational power for the device.
33984
Analog Integrated Circuit Device Data
Freescale Semiconductor
5
ELECTRICAL CHARACTERISTICS
MAXIMUM RATINGS
ELECTRICAL CHARACTERISTICS
MAXIMUM RATINGS
Table 3. Maximum Ratings
All voltages are with respect to ground unless otherwise noted.
Symbol
Rating
Value
Unit
Notes
Operating Voltage Range
Steady-state
-16 to 41
V
VDD
VDD Supply Voltage
-0.3 to 5.5
V
VIN[0:1], RST, FSI,
CSNS, SI, SCLK,
Input/Output Voltage
- 0.3 to 7.0
V
(1)
- 0.3 to VDD + 0.3
V
(1)
ELECTRICAL RATINGS
VPWR
CS, FS
VSO
SO Output Voltage
ICL(WAKE)
WAKE Input Clamp Current
2.5
mA
ICL(CSNS)
CSNS Input Clamp Current
10
mA
VHS
Output Voltage
Positive
Negative
41
-15
V
IHS[0:1]
Output Current
30
A
(2)
ECL[0:1]
Output Clamp Energy
0.5
J
(3)
V
(4)
VESD1
VESD3
ESD Voltage
Human Body Model (HBM)
Charge Device Model (CDM)
Corner Pins (1, 12, 15, 16)
All Other Pins (2, 11, 13, 14)
± 2000
±750
±500
Notes
1. Exceeding this voltage limit may cause permanent damage to the device.
2. Continuous high-side output current rating so long as maximum junction temperature is not exceeded. Calculation of maximum output current using
package thermal resistance is required.
3. Active clamp energy using single-pulse method (L = 16 mH, RL = 0, VPWR = 12 V, TJ = 150 °C).
4.
ESD1 testing is performed in accordance with the Human Body Model (HBM) (CZAP = 100 pF, RZAP = 1500 ESD3 testing is performed in
accordance with the Charge Device Model (CDM), Robotic (CZAP = 4.0 pF).
33984
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Analog Integrated Circuit Device Data
Freescale Semiconductor
ELECTRICAL CHARACTERISTICS
MAXIMUM RATINGS
Table 3. Maximum Ratings (continued)
All voltages are with respect to ground unless otherwise noted.
Symbol
Rating
Value
Unit
Notes
Operating Temperature
Ambient
Junction
- 40 to 125
- 40 to 150
C
TSTG
Storage Temperature
- 55 to 150
C
RJC
RJA
Thermal Resistance
Junction-to-Case
Junction-to-Ambient
0.7 x VDD,
RST = VLOGIC HIGH
–
–
5.0
mA
–
–
–
–
10
50
A
4.5
5.0
5.5
V
IPWR(SLEEP)
Sleep State Supply Current (VPWR < 14 V, RST < 0.5 V,
WAKE < 0.5 V)
TJ = 25 C
TJ = 85 C
VDD(ON)
VDD Supply Voltage
IDD(ON)
VDD Supply Current
No SPI Communication
3.0 MHz SPI Communication
–
–
–
–
1.0
5.0
mA
IDD(SLEEP)
VDD Sleep State Current
–
–
5.0
A
VPWR(OV)
Overvoltage Shutdown Threshold
28
32
36
V
VPWR(OVHYS)
Overvoltage Shutdown Hysteresis
0.2
0.8
1.5
V
Undervoltage Output Shutdown Threshold
5.0
5.5
6.0
V
(8)
(9)
VPWR(UV)
VPWR(UVHYS)
Undervoltage Hysteresis
–
0.25
–
V
VPWR(UVPOR)
Undervoltage Power-ON Reset
–
–
5.0
V
–
–
–
–
–
–
6.0
4.0
4.0
m
–
–
–
–
–
–
10.2
6.8
6.8
–
–
8.0
POWER OUTPUT
RDS(on)
RDS(on)
Output Drain-to-Source ON Resistance (IHS[0:1] = 15 A, TJ = 25 C)
VPWR = 6.0 V
VPWR = 10 V
VPWR = 13 V
Output Drain-to-Source ON Resistance (IHS[0:1] = 15 A, TJ = 150 C)
VPWR = 6.0 V
VPWR = 10 V
VPWR = 13 V
RDS(on)
Output Source-to-Drain ON Resistance IHS[0:1] = 15 A, TJ = 25 C
VPWR = -12 V
m
m
(10)
Notes
8. This applies to all internal device logic supplied by VPWR and assumes the external VDD supply is within specification.
9.
10.
This applies when the undervoltage fault is not latched (IN[0 : 1] = 0).
Source-Drain ON Resistance (Reverse Drain-to-Source ON Resistance) with negative polarity VPWR.
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Analog Integrated Circuit Device Data
Freescale Semiconductor
ELECTRICAL CHARACTERISTICS
STATIC ELECTRICAL CHARACTERISTICS
Table 4. Static Electrical Characteristics (continued)
Characteristics noted under conditions 4.5 V VDD 5.5 V, 6.0 V VPWR 27 V, -40 C TA 125 C, unless otherwise noted. Typical
values noted reflect the approximate parameter mean at TA = 25 C under nominal conditions, unless otherwise noted.
Symbol
Characteristic
Min
Typ
Max
Unit
A
Notes
POWER OUTPUT (CONTINUED)
IOCH0
IOCH1
Output Overcurrent High Detection Levels (9.0 V < VPWR < 16 V)
SOCH = 0
SOCH = 1
80
60
100
75
120
90
IOCL0
IOCL1
IOCL2
IOCL3
IOCL4
IOCL5
IOCL6
IOCL7
Overcurrent Low Detection Levels (SOCL[2:0])
000
001
010
011
100
101
110
111
21
18
16
14
12
10
8.0
6.0
25
22.5
20
17.5
15
12.5
10
7.5
29
27
24
21
18
15
12
9.0
CSR0
CSR1
Current Sense Ratio (9.0 V < VPWR < 16 V, CSNS < 4.5 V)
DICR D2 = 0
DICR D2 = 1
–
–
1/20500
1/41000
–
–
CSR0_ACC
Current Sense Ratio (CSR0) Accuracy
Output Current
5.0 A
10 A
12.5 A
15 A
20 A
25 A
- 20
-14
-13
-12
-13
-13
–
–
–
–
–
–
20
14
13
12
13
13
CSR1_ACC
Current Sense Ratio (CSR1) Accuracy
Output Current
5.0 A
10 A
12.5 A
15 A
20 A
25 A
- 25
-19
-18
-17
-18
-18
–
–
–
–
–
–
25
19
18
17
18
18
VCL(CSNS)
Current Sense Clamp Voltage
CSNS Open; IHS[0:1] = 29 A
4.5
6.0
7.0
V
IOLDC
Open Load Detection Current
30
–
100
A
Output Fault Detection Threshold
Output Programmed OFF
2.0
3.0
4.0
V
VCL
Output Negative Clamp Voltage
0.5 A < IHS[0:1] < 2.0 A, Output OFF
- 20
–
-15
V
TSD
Overtemperature Shutdown
160
175
190
C
(12)
Overtemperature Shutdown Hysteresis
5.0
–
20
C
(12)
VOLD(THRES)
TSD(HYS)
A
–
%
%
(11)
Notes
11. Output OFF Open Load Detection Current is the current required to flow through the load for the purpose of detecting the existence of an open
load condition when the specific output is commanded OFF.
12. Guaranteed by process monitoring. Not production tested.
33984
Analog Integrated Circuit Device Data
Freescale Semiconductor
9
ELECTRICAL CHARACTERISTICS
STATIC ELECTRICAL CHARACTERISTICS
Table 4. Static Electrical Characteristics (continued)
Characteristics noted under conditions 4.5 V VDD 5.5 V, 6.0 V VPWR 27 V, -40 C TA 125 C, unless otherwise noted. Typical
values noted reflect the approximate parameter mean at TA = 25 C under nominal conditions, unless otherwise noted.
Symbol
Characteristic
Min
Typ
Max
Unit
Notes
Control Interface
VIH
Input Logic High-voltage
0.7 x VDD
–
–
V
(13)
VIL
Input Logic Low-voltage
–
–
0.2 x VDD
V
(13)
Input Logic Voltage Hysteresis
100
600
1200
mV
(14)
IDWN
Input Logic Pull-down Current (SCLK, IN, SI)
5.0
–
20
A
VRST
RST Input Voltage Range
4.5
5.0
5.5
V
CSO
SO, FS Tri-state Capacitance
–
–
20
pF
100
200
400
k
–
4.0
12
pF
(15)
(16)
VIN[0:1] (HYS)
RDWN
CIN
Input Logic Pull-down Resistor (RST) and WAKE
Input Capacitance
VCL(WAKE)
WAKE Input Clamp Voltage
ICL(WAKE) < 2.5 mA
7.0
–
14
V
VF(WAKE)
WAKE Input Forward Voltage
ICL(WAKE) = - 2.5 mA
- 2.0
–
- 0.3
V
VSOH
SO High-state Output Voltage
IOH = 1.0 mA
0.8 x VDD
–
–
V
–
0.2
0.4
V
SO Tri-state Leakage Current
CS > 0.7 VDD
- 5.0
0.0
5.0
A
Input Logic Pull-up Current
CS, VIN[0:1] > 0.7 x VDD
5.0
–
20
A
–
6.0
15
40
0
6.5
17
Infinite
1.0
7.0
19
–
VSOL
ISO(LEAK)
IUP
RFS
RFSDIS
RFSOFFOFF
RFSONOFF
RFSONON
FS, SO Low-state Output Voltage
IOL = -1.6 mA
FSI Input Pin External Pull-down Resistance
FSI Disabled, HS[0:1] Indeterminate
FSI Enabled, HS[0:1] OFF
FSI Enabled, HS0 ON, HS1 OFF
FSI Enabled, HS[0:1] ON
(15)
(17)
k
Notes
13. Upper and lower logic threshold voltage range applies to SI, CS, SCLK, RST, IN[0:1], and WAKE input signals. The WAKE and RST signals may
be supplied by a derived voltage reference to VPWR.
14.
15.
16.
17.
No hysteresis on FSI and WAKE pins. Parameter is guaranteed by processing monitoring but is not production tested.
Input capacitance of SI, CS, SCLK, RST, and WAKE. This parameter is guaranteed by process monitoring but is not production tested.
The current must be limited by a series resistance when using voltages > 7.0 V.
Pull-up current is with CS OPEN. CS has an active internal pull-up to VDD.
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Analog Integrated Circuit Device Data
Freescale Semiconductor
ELECTRICAL CHARACTERISTICS
DYNAMIC ELECTRICAL CHARACTERISTICS
DYNAMIC ELECTRICAL CHARACTERISTICS
Table 5. Dynamic Electrical Characteristics
Characteristics noted under conditions 4.5 V VDD 5.5 V, 6.0 V VPWR 27 V, -40 C TA 125 C, unless otherwise noted. Typical
values noted reflect the approximate parameter mean at TA = 25 C under nominal conditions, unless otherwise noted.
Symbol
Characteristic
Min
Typ
Max
Unit
Notes
POWER OUTPUT TIMING
SRRA_SLOW
Output Rising Slow Slew Rate A (DICR D3 = 0)
9.0 V < VPWR < 16 V
0.15
0.5
1.0
V/s
(18)
SRRB_SLOW
Output Rising Slow Slew Rate B (DICR D3 = 0)
9.0 V < VPWR < 16 V
0.06
0.2
0.6
V/s
(19)
SRRA_FAST
Output Rising Fast Slew Rate A (DICR D3 = 1)
9.0 V < VPWR < 16 V
0.3
0.8
3.2
V/s
(18)
SRRB_FAST
Output Rising Fast Slew Rate B (DICR D3 = 1)
9.0 V < VPWR < 16 V
0.06
0.2
2.4
V/s
(19)
SRFA_SLOW
Output Falling Slow Slew Rate A (DICR D3 = 0)
9.0 V < VPWR < 16 V
0.15
0.5
1.0
V/s
(18)
SRFB_SLOW
Output Falling Slow Slew Rate B (DICR D3 = 0)
9.0 V < VPWR < 16 V
0.06
0.2
0.6
V/s
(19)
SRFA_FAST
Output Falling Fast Slew Rate A (DICR D3 = 1)
9.0 V < VPWR < 16 V
0.6
1.6
3.2
V/s
(18)
SRFB_FAST
Output Falling Fast Slew Rate B (DICR D3 = 1)
9.0 V < VPWR < 16 V
0.2
0.7
2.4
V/s
(19)
Output Turn-ON Delay Time in Fast/Slow Slew Rate
DICR = 0, DICR = 1
1.0
18
100
s
(20)
t DLY_SLOW(OFF)
Output Turn-OFF Delay Time in Slow Slew Rate Mode
DICR = 0
10
115
250
s
(21)
t DLY_FAST(OFF)
Output Turn-OFF Delay Time in Fast Slew Rate Mode
DICR = 1
5.0
30
100
s
(21)
–
300
–
Hz
t DLY(ON)
f PWM
Direct Input Switching Frequency (DICR D3 = 0)
t OCL0
t OCL1
t OCL2
t OCL3
Overcurrent Detection Blanking Time (OCLT [1:0])
00
01
10
11
108
7.0
0.8
0.08
155
10
1.2
0.15
202
13
1.6
0.25
t OCH
Overcurrent High Detection Blanking Time
1.0
10
20
s
–
–
10
s
t CNSVAL
CS to CSNS Valid Time
ms
(22)
Notes
18. Rise and Fall Slew Rates A measured across a 5.0 resistive load at high-side output = 0.5 V to VPWR - 3.5 V. These parameters are guaranteed
by process monitoring.
19. Rise and Fall Slew Rates B measured across a 5.0 resistive load at high-side output = VPWR - 3.5 V to VPWR - 0.5 V. These parameters are
guaranteed by process monitoring.
20. Turn-ON delay time measured from rising edge of IN[0:1] signal would turn the output ON to VHS[0:1] = 0.5 V with RL = 5.0 resistive load.
21.
Turn-OFF delay time measured from falling edge would turn the output OFF to VHS[0:1] = VPWR - 0.5 V with RL = 5.0 resistive load.
22.
Time necessary for the CSNS to be within ±5.0% of the targeted value.
33984
Analog Integrated Circuit Device Data
Freescale Semiconductor
11
ELECTRICAL CHARACTERISTICS
DYNAMIC ELECTRICAL CHARACTERISTICS
Table 5. Dynamic Electrical Characteristics (continued)
Characteristics noted under conditions 4.5 V VDD 5.5 V, 6.0 V VPWR 27 V, -40 C TA 125 C, unless otherwise noted. Typical
values noted reflect the approximate parameter mean at TA = 25 C under nominal conditions, unless otherwise noted.
Symbol
Characteristic
Min
Typ
Max
Unit
Notes
POWER OUTPUT TIMING (CONTINUED)
t OSD0
t OSD1
t OSD2
t OSD3
t OSD4
t OSD5
t OSD6
t OSD7
HS1 Switching Delay Time (OSD[2:0])
000
001
010
011
100
101
110
111
–
55
110
165
220
275
330
385
0
75
150
225
300
375
450
525
–
95
190
285
380
475
570
665
t OSD0
t OSD1
t OSD2
t OSD3
t OSD4
t OSD5
t OSD6
t OSD7
HS0 Switching Delay Time (OSD[2:0])
000
001
010
011
100
101
110
111
–
–
110
110
220
220
330
330
0
0
150
150
300
300
450
450
–
–
190
190
380
380
570
570
Watchdog Timeout (WD [1:0])
00
01
10
11
434
207
1750
875
620
310
2500
1250
806
403
3250
1625
Recommended Frequency of SPI Operation
–
–
3.0
MHz
Required Low State Duration for RST
–
50
350
ns
(24)
Rising Edge of CS to Falling Edge of CS (Required Setup Time)
–
–
300
ns
(25)
t ENBL
Rising Edge of RST to Falling Edge of CS (Required Setup Time)
–
–
5.0
s
(25)
t LEAD
Falling Edge of CS to Rising Edge of SCLK (Required Setup Time)
–
50
167
ns
(25)
t WSCLKh
Required High State Duration of SCLK (Required Setup Time)
–
–
167
ns
(25)
t WSCLKl
Required Low State Duration of SCLK (Required Setup Time)
–
–
167
ns
(25)
Falling Edge of SCLK to Rising Edge of CS (Required Setup Time)
–
50
167
ns
(25)
t SI(SU)
SI to Falling Edge of SCLK (Required Setup Time)
–
25
83
ns
(26)
t SI(HOLD)
Falling Edge of SCLK to SI (Required Setup Time)
–
25
83
ns
(27)
t RSO
SO Rise Time
CL = 200 pF
–
25
50
ns
t FSO
SO Fall Time
CL = 200 pF
–
25
50
ns
t WDTO0
t WDTO1
t WDTO2
t WDTO3
f SPI
t WRST
t CS
t LAG
ms
ms
ms
(23)
Notes
23. Watchdog timeout delay measured from the rising edge of WAKE to RST from a sleep-state condition to output turn-ON with the output driven
OFF and FSI floating. The values shown are for WDR setting of [00]. The accuracy of tWDTO is consistent for all configured watchdog timeouts.
24.
25.
26.
RST low duration measured with outputs enabled and going to OFF or disabled condition.
Maximum setup time required for the 33984 is the minimum guaranteed time needed from the microcontroller.
Rise and Fall time of incoming SI, CS, and SCLK signals suggested for design consideration to prevent the occurrence of double pulsing.
33984
12
Analog Integrated Circuit Device Data
Freescale Semiconductor
ELECTRICAL CHARACTERISTICS
TIMING DIAGRAMS
Table 5. Dynamic Electrical Characteristics (continued)
Characteristics noted under conditions 4.5 V VDD 5.5 V, 6.0 V VPWR 27 V, -40 C TA 125 C, unless otherwise noted. Typical
values noted reflect the approximate parameter mean at TA = 25 C under nominal conditions, unless otherwise noted.
Symbol
Characteristic
Min
Typ
Max
Unit
Notes
SPI INTERFACE CHARACTERISTICS
t RSI
SI, CS, SCLK, Incoming Signal Rise Time
–
–
50
ns
(27)
t RSI
SI, CS, SCLK, Incoming Signal Fall Time
–
–
50
ns
(27)
t SO(EN)
Time from Falling Edge of CS to SO Low-impedance
–
–
145
ns
(28)
t SO(DIS)
Time from Rising Edge of CS to SO High-impedance
–
65
145
ns
(29)
Time from Rising Edge of SCLK to SO Data Valid
0.2 x VDD SO 0.8 x VDD, CL = 200 pF
–
65
105
ns
(30)
t VALID
Notes
27.
28.
29.
30.
Rise and Fall time of incoming SI, CS, and SCLK signals suggested for design consideration to prevent the occurrence of double pulsing.
Time required for output status data to be available for use at SO. 1.0 kon pull-up on CS.
Time required for output status data to be terminated at SO. 1.0 kon pull-up on CS.
Time required to obtain valid data out from SO following the rise of SCLK.
TIMING DIAGRAMS
CS
VPWR
VPWR
0.5V V
VVPWR
PWR --0.5
SRfB
SRFB_SLOW & SRFB_FAST
SRRB_SLOW & SRRB_FAST
SRrB
VPWR
-3.5
VPWR
- 3V V
SRfA
SRFA_SLOW & SRFA_FAST
SRRA_SLOW & SRRA_FAST
SRrA
HS
0.5V0.5
V
t DLY_SLOW(OFF) & tDLY_FAST(OFF)
Tdly(off)
t DLY(ON)
Tdly
(on)
Figure 4. Output Slew Rate and Time Delays
IOCHx
Load
Current
IOCLx
t OCH
Time
t OCLx
Figure 5. Overcurrent Shutdown
33984
Analog Integrated Circuit Device Data
Freescale Semiconductor
13
ELECTRICAL CHARACTERISTICS
TIMING DIAGRAMS
IOCH0
IOCH1
IOCL0
IOCL1
Load
Current
IOCL2
IOCL3
IOCL4
IOCL5
IOCL6
IOCL7
Time
t OCHx
t OCL3 t OCL2
t OCL1
t OCL0
Figure 6. Overcurrent Low and High Detection
Figure 6 illustrates the overcurrent detection level (Ioclx, Iochx) the device can reach for each overcurrent detection blanking time (tochx,
toclx):
• During tochx, the device can reach up to Ioch0 overcurrent level.
• During tocl3 or tocl2 or tocl1 or tocl0, the device can be programmed to detect up to Iocl0.
VIH
V
IH
RSTB
RST
0.2
x VDD
0.2
VDD
VIL
VIL
TwRSTB
t WRST
t ENBL
tTCSB
CS
TENBL
VIH
V
0.7
x VDD
0.7VDD
CS
CSB
IH
0.2
x VDD
0.7VDD
tTlead
LEAD
VIL
V
IL
t RSI
t WSCLKh
TwSCLKh
TrSI
t LAG Tlag
0.70.7VDD
x VDD
SCLK
SCLK
VIH
VIH
0.2 x VDD
0.2VDD
VIL
V
t TSIsu
SI(SU)
IL
t WSCLKl
TwSCLKl
t SI(HOLD)
TSI(hold)
SI
SI
Don’t Care
0.7
VDD
0.7 xVDD
0.2VDD
0.2
x VDD
tTfSI
FSI
VIH
V
Valid
Don’t Care
Valid
Don’t Care
IH
VIH
VIL
Figure 7. Input Timing Switching Characteristics
33984
14
Analog Integrated Circuit Device Data
Freescale Semiconductor
ELECTRICAL CHARACTERISTICS
TIMING DIAGRAMS
t FSI
t RSI
TrSI
TfSI
VOH
VOH
3.5 V
3.5V
50%
SCLK
SCLK
1.0VV
1.0
VOL
VOL
t SO(EN)
TdlyLH
SO
SO
0.7 xVDD
VDD
0.20.2
VDD
x VDD
Low-to-High
Low
to High
TrSO
t RSO
VOH
VOH
VOL
VOL
VALID
tTVALID
SO
TfSO
t FSO
SO
VOH
VOH
0.7VDD
x VDD
High to Low 0.7
High-to-Low
0.2VDD
0.2 x VDD
TdlyHL
VOL
VOL
t SO(DIS)
Figure 8. SCLK Waveform and Valid SO Data Delay Time
33984
Analog Integrated Circuit Device Data
Freescale Semiconductor
15
FUNCTIONAL DESCRIPTION
FUNCTIONAL PIN DESCRIPTION
FUNCTIONAL DESCRIPTION
INTRODUCTION
The 33984 is a dual self-protected 4.0 m silicon switch used to replace electromechanical relays, fuses, and discrete devices in power
management applications. The 33984 is designed for harsh environments, and it includes self-recovery features. The device is suitable
for loads with high inrush current, as well as motors and all types of resistive and inductive loads.
Programming, control, and diagnostics are implemented via the serial peripheral interface (SPI). A dedicated parallel input is available for
alternate and pulse width modulation (PWM) control of each output. SPI-programmable fault trip thresholds allow the device to be adjusted
for optimal performance in the application. The 33984 is packaged in a power-enhanced 12 mm x 12 mm non-leaded PQFN package with
exposed tabs.
FUNCTIONAL PIN DESCRIPTION
OUTPUT CURRENT MONITORING (CSNS)
This pin is used to output a current proportional to the designated HS0-1 output. The current is fed into a ground-referenced resistor and
its voltage is monitored by an MCU's A/D. The channel to be monitored is selected via the SPI. This pin can be tri-stated through the SPI.
WAKE (WAKE)
This pin is used to input a logic [1] signal so as to enable the watchdog timer function. An internal clamp protects this pin from high
damaging voltages when the output is current limited with an external resistor. This input has a passive internal pull-down.
RESET (RST)
This input pin is used to initialize the device configuration and fault registers, as well as place the device in a low-current Sleep mode. The
pin also starts the watchdog timer when transitioning from logic Low to logic High. This pin should not be allowed to be logic High until VDD
is in regulation. This pin has a passive internal pull-down.
DIRECT IN 0 & 1 (INx)
This input pin is used to directly control the output HS0 and 1. This input has an active internal pull-down current source and requires
CMOS logic levels. This input may be configured via the SPI.
FAULT STATUS (FS)
This is an open drain configured output requiring an external pull-up resistor to VDD for fault reporting. When a device fault condition is
detected, this pin is active Low. Specific device diagnostic faults are reported via the SPI SO pin.
FAIL-SAFE INPUT (FSI)
The value of the resistance connected between this pin and ground determines the state of the outputs after a watchdog timeout occurs.
Depending on the resistance value, either all outputs are OFF, ON, or the output HS0 only is ON. When the FSI pin is connected to GND,
the watchdog circuit and fail-safe operation are disabled. This pin incorporates an active internal pull-up current source.
CHIP SELECT (CS)
This input pin is connected to a chip select output of a master microcontroller (MCU). The MCU determines which device is addressed
(selected) to receive data by pulling the CS pin of the selected device logic Low, enabling SPI communication with the device. Other
unselected devices on the serial link having their CS pins pulled-up logic High disregard the SPI communication data sent. This pin
incorporates an active internal pull-up current source.
SERIAL CLOCK (SCLK)
This input pin is connected to the MCU providing the required bit shift clock for SPI communication. It transitions one time per bit transferred
at an operating frequency, fSPI, defined by the communication interface. The 50 percent duty cycle CMOS-level serial clock signal is idle
between command transfers. The signal is used to shift data into and out of the device. This input has an active internal pull-down current
source.
33984
16
Analog Integrated Circuit Device Data
Freescale Semiconductor
FUNCTIONAL DESCRIPTION
FUNCTIONAL PIN DESCRIPTION
SERIAL INPUT (SI)
This is a command data input pin connected to the SPI Serial Data Output of the MCU or to the SO pin of the previous device of
a daisy chain of devices. The input requires CMOS logic-level signals and incorporates an active internal pull-down current
source. Device control is facilitated by the input's receiving the MSB first of a serial 8-bit control command. The MCU ensures
data is available upon the falling edge of SCLK. The logic state of SI present upon the rising edge of SCLK loads this bit command
into the internal command shift register.
DIGITAL DRAIN VOLTAGE (VDD)
This is an external voltage input pin used to supply power to the SPI circuit. In the event VDD is lost, an internal supply provides
power to a portion of the logic, ensuring limited functionality of the device. All device configuration registers are reset.
SERIAL OUTPUT (SO)
This output pin is connected to the SPI Serial Data Input pin of the MCU or to the SI pin of the next device of a daisy chain of
devices. This output remains tri-stated (high-impedance OFF condition) so long as the CS pin of the device is logic HIGH. SO is
only active when the CS pin of the device is asserted logic Low. The generated SO output signals are CMOS logic levels. SO
output data is available on the falling edge of SCLK and transitions immediately on the rising edge of SCLK.
POSITIVE POWER SUPPLY (VPWR)
This pin connects to the positive power supply and is the source input of operational power for the device. The VPWR pin is a
backside surface mount tab of the package.
HIGH-SIDE OUTPUT 0 & 1 (HSx)
This pin protects 4.0 m high-side power output to the load.
33984
Analog Integrated Circuit Device Data
Freescale Semiconductor
17
FUNCTIONAL DESCRIPTION
FUNCTIONAL INTERNAL BLOCK DESCRIPTION
FUNCTIONAL INTERNAL BLOCK DESCRIPTION
POWER SUPPLY
SELF-PROTECTED
HIGH-SIDE SWITCH
MCU INTERFACE AND
OUTPUT CONTROL
HS [0:1]
SPI INTERFACE
MCU
INTERFACE
PARALLEL CONTROL
INPUTS
POWER SUPPLY
The 33984 is designed to operate from 4.0 V to 28 V on the VPWR pin. Characteristics are provided from 6.0 V to 20 V for the device. The
VPWR pin supplies power to internal regulator, analog, and logic circuit blocks. The VDD supply is used for serial peripheral interface (SPI)
communication in order to configure and diagnose the device. This IC architecture provides a low quiescent current sleep mode. Applying
VPWR and VDD to the device places the device in the Normal mode. The device transits to Fail-safe mode in case of failures on the SPI
(watchdog timeout).
HIGH-SIDE SWITCH: HS[0:1]
Those pins are the high-side outputs controlling multiple automotive loads with high inrush current, as well as motors and all types of
resistive and inductive loads. This N-channel MOSFET with 4.0 m RDS(ON), is self-protected and each N-channel presents extended
diagnostics in order to detect load disconnections and short-circuit fault conditions. The HS[0:1] outputs are actively clamped during a turnoff of inductive loads.
MCU INTERFACE AND OUTPUT CONTROL
In Normal mode, the loads are controlled directly from the MCU through the SPI. With a dedicated SPI command, it is possible to
independently turn on and off several loads are PWMed at the same frequency, and duty cycles with only one PWM signal. An analog
feedback output provides a current proportional to each load current. The SPI is used to configure and to read the diagnostic status (faults)
of the high-side output. The reported fault conditions are: open load, short-circuit to ground (OCLO-resistive and OCHI-severe shortcircuit), thermal shutdown, and under/overvoltage.
In Fail-safe mode, the loads are controlled with dedicated parallel input pins. The device is configured in default mode.
33984
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Analog Integrated Circuit Device Data
Freescale Semiconductor
FUNCTIONAL DEVICE OPERATION
OPERATIONAL MODES
FUNCTIONAL DEVICE OPERATION
OPERATIONAL MODES
The 33984 has four operating modes: Sleep, Normal, Fault, and Fail-safe. Table 6 summarizes details contained in succeeding
paragraphs.
Table 6. Fail-safe Operation and Transitions to Other 33984 Modes
Mode
FS
WAKE
RST
WDTO
Sleep
x
0
0
x
Device is in Sleep mode. All outputs are OFF.
Normal
1
x
1
No
Normal mode. Watchdog is active if enabled.
0
1
x
No
The device is currently in Fault mode. The faulted output(s) is (are) OFF.
0
x
1
1
0
1
1
1
1
Yes
Watchdog has timed out and the device is in Fail-safe mode. The outputs are as configured with the RFS
resistor connected to FSI. RST and WAKE must be transitioned to logic [0] simultaneously to bring the
device out of the Fail-safe mode or momentarily tied the FSI pin to ground.
1
1
0
Fault
Fail-safe
Comments
x = Don’t care.
SLEEP MODE
The default mode of the 33984 is the Sleep mode. This is the state of the device after first applying battery voltage (VPWR), prior to any
I/O transitions. This is also the state of the device when the WAKE and RST are both logic [0]. In the Sleep mode, the output and all unused
internal circuitry, such as the internal 5.0 V regulator, are off to minimize current draw. In addition, all SPI-configurable features of the
device are as if set to logic [0]. The device transitions to the Normal or Fail-safe operating modes based on the WAKE and RST inputs as
defined in Table 6.
NORMAL MODE
The 33984 is in Normal mode when:
• VPWR is within the normal voltage range.
• RST pin is logic [1].
• No fault has occurred.
FAIL-SAFE AND WATCHDOG
If the FSI input is not grounded, the watchdog timeout detection is active when either the WAKE or RST input pin transitions from logic [0]
to logic [1]. The WAKE input is capable of being pulled up to VPWR with a series of limiting resistance limits the internal clamp current
according to the specification.
The watchdog timeout is a multiple of an internal oscillator and is specified in Table 15. As long as the WD bit (D7) of an incoming SPI
message is toggled within the minimum watchdog timeout period (WDTO), based on the programmed value of the WDR the device
operates normally. If an internal watchdog timeout occurs before the WD bit, the device reverts to a Fail-safe mode until the device is
reinitialized.
During the Fail-safe mode, the outputs are ON or OFF depending upon the resistor RFS connected to the FSI pin, regardless of the state
of the various direct inputs and modes (Table 7). In this mode, the SPI register content is retained except for overcurrent high and low
detection levels and timing, which are reset to their default value (SOCL, SOCH, and OCLT). Then the watchdog, overvoltage,
overtemperature, and overcurrent circuitry (with default value) are fully operational.
33984
Analog Integrated Circuit Device Data
Freescale Semiconductor
19
FUNCTIONAL DEVICE OPERATION
PROTECTION AND DIAGNOSTIC FEATURES
Table 7. Output State During Fail-safe Mode
RFS (k)
High-side State
0
Fail-safe mode Disabled
6.0
Both HS0 and HS1 OFF
15
HS0 ON, HS1 OFF
30
Both HS0 and HS1 ON
The Fail-safe mode can be detected by monitoring the WDTO bit D2 of the WD register. This bit is logic [1] when the device is in Fail-safe
mode. The device can be brought out of the Fail-safe mode by transitioning the WAKE and RST pins from logic [1] to logic [0] or forcing
the FSI pin to logic [0]. Table 6 summarizes the various methods for resetting the device from the latched Fail-safe mode. If the FSI pin is
tied to GND, the watchdog Fail-safe operation is disabled.
LOSS OF VDD
If the external 5.0 V supply is not within specification, or even disconnected, all register content is reset. The two outputs can still be driven
by the direct inputs IN 1:IN0. The 33984 uses the battery input to power the output MOSFET related current sense circuitry and any other
internal logic providing fail-safe device operation with no VDD supplied. In this state, the watchdog, overvoltage, overtemperature, and
overcurrent circuitry are fully operational with default values.
FAULT MODE
The 33984 indicates the following faults as they occur by driving the FS pin to logic [0]:
• Overtemperature fault
• Open load fault
• Overcurrent fault (high and low)
• Overvoltage and undervoltage fault
The FS pin automatically returns to logic [1] when the fault condition is removed, except for overcurrent and in some cases undervoltage.
fault information is retained in the fault register and is available (and reset) via the SO pin during the first valid SPI communication (refer
to Table 17).
PROTECTION AND DIAGNOSTIC FEATURES
OVERTEMPERATURE FAULT (NON-LATCHING)
The 33984 incorporates overtemperature detection and shutdown circuitry in each output structure. Overtemperature detection is enabled
when an output is in the ON state.
For the output, an overtemperature fault (OTF) condition results in the faulted output turning OFF until the temperature falls below the
TSD(HYS). This cycle continues indefinitely until action is taken by the MCU to shut OFF the output, or until the offending load is removed.
When experiencing this fault, the OTF fault bit is set in the status register and cleared after either a valid SPI read or a power reset of the
device.
OVERVOLTAGE FAULT (NON-LATCHING)
The 33984 shuts down the output during an overvoltage fault (OVF) condition on the VPWR pin. The output remains in the OFF state until
the overvoltage condition is removed. When experiencing this fault, the OVF fault bit is set in the bit OD1 and cleared after either a valid
SPI read or a power reset of the device. The overvoltage protection and diagnostic can be disabled trough the SPI (bit OV_dis).
UNDERVOLTAGE SHUTDOWN (LATCHING OR NON-LATCHING)
The output(s) latches off at some battery voltage below 6.0 V. As long as the VDD level stays within the normal specified range, the internal
logic states within the device is sustained.
In the case where battery voltage drops below the undervoltage threshold (VPWRUV) output turns off, FS goes to logic [0], and the fault
register UVF bit is set to 1.
Two cases need to be considered when the battery level recovers :
• If output(s) command is (are) low, FS goes to logic [1] but the UVF bit remains set to 1 until the next read operation.
• If the output command is ON, then FS remains at logic [0]. The output must be turned OFF and ON again to re-enable the state of
output and release FS . The UVF bit remains set to 1 until the next read operation.
The undervoltage protection can be disabled through the SPI (bit UV_dis = 1). In this case, the FS and UVF bits do not report any
undervoltage fault condition and the output state is not changed as long as battery voltage does not drop any lower than 2.5 V.
33984
20
Analog Integrated Circuit Device Data
Freescale Semiconductor
FUNCTIONAL DEVICE OPERATION
PROTECTION AND DIAGNOSTIC FEATURES
OPEN LOAD FAULT (NON-LATCHING)
The 33984 incorporates open load detection circuitry on each output. Output open load fault (OLF) is detected and reported as a fault
condition when this output is disabled (OFF). The open load fault is detected and latched into the status register after the internal gate
voltage is pulled low enough to turn OFF the output. The OLF fault bit is set in the status register. If the open load fault is removed, the
status register is cleared after reading the register.
The open load protection can be disabled trough SPI (bit OL_dis). It is recommended to disable the open load detection circuitry (OL_dis
bit sets to logic [1]) in case of permanent open load fault condition.
OVERCURRENT FAULT (LATCHING)
The device has eight programmable overcurrent low detection levels (IOCL) and two programmable overcurrent high detection levels
(IOCH) for maximum device protection. The two selectable, simultaneously active overcurrent detection levels, defined by IOCH and IOCL,
are illustrated in Figure 6. The eight different overcurrent low detect levels (IOCL0 : IOCL7) are likewise illustrated in Figure 6.
If the load current level ever reaches the selected overcurrent low detect level and the overcurrent condition exceeds the programmed
overcurrent time period (tOCx), the device latches the effected output OFF. If at any time the current reaches the selected IOCH level, then
the device immediately latches the fault and turn OFF the output, regardless of the selected tOCL driver. For both cases, the device output
stays off indefinitely until the device is commanded OFF and then ON again.
REVERSE BATTERY
The output survives the application of reverse voltage as low as -16 V. Under these conditions, the output’s gates are enhanced to keep
the junction temperature less than 150 °C. The ON resistance of the output is fairly similar in the Normal mode. No additional passive
components are required.
GROUND DISCONNECT PROTECTION
In the event the 33984 ground is disconnected from load ground, the device protects itself and safely turns OFF the output regardless the
state of the output at the time of disconnection. A 10 k resistor needs to be added between the WAKE pin and the rest of the circuitry in
order to ensure the device turns off in case of ground disconnect, and to prevent this pin from exceeding its maximum ratings.
Table 8. Device Behavior in Case of Undervoltage
High-side
Switch (VPWR
Battery
Voltage)
UV Enable
IN = 0
(Falling VPWR)
UV Enable
IN = 0
(Rising VPWR)
UV Enable
IN = 1
(Falling VPWR)
UV Enable
IN = 1
(Rising VPWR)
UV Disable
IN = 0 (Falling or
Rising VPWR)
UV Disable
IN = 1
(Falling or
Rising VPWR)
OFF
OFF
ON
OFF
OFF
ON
FS State
1
1
1
0
1
1
SPI Fault
Register UVF
Bit
0
1 until next read
0
1
0
0
Output State
OFF
OFF
OFF
OFF
OFF
ON
FS State
0
0
0
0
1
1
SPI Fault
Register UVF
Bit
1
1
1
1
0
0
Output State
OFF
OFF
OFF
OFF
OFF
ON
1
1
1
1
1
1
SPI Fault
Register UVF
Bit
1 until next read
1
1 until next read
1 until next read
0
0
Output State
OFF
OFF
OFF
OFF
OFF
OFF
1
1
1
1
1
1
1 until next read
1 until next read
1 until next read
1 until next read
0
0
State
Output State
VPWR >
VPWRUV
VPWRUV >
VPWR >
UVPOR
UVPOR >
VPWR > 2.5 V
2.5 V > VPWR >
0V
FS State
FS State
SPI Fault
Register UVF
Bit
33984
Analog Integrated Circuit Device Data
Freescale Semiconductor
21
FUNCTIONAL DEVICE OPERATION
LOGIC COMMANDS AND REGISTERS
Table 8. Device Behavior in Case of Undervoltage (continued)
High-side
Switch (VPWR
Battery
Voltage)
State
UV Enable
IN = 0
(Falling VPWR)
UV Enable
IN = 0
(Rising VPWR)
UV fault is
not latched
UV fault is
not latched
Comments
UV Enable
IN = 1
(Falling VPWR)
UV Enable
IN = 1
(Rising VPWR)
UV Disable
IN = 0 (Falling or
Rising VPWR)
UV Disable
IN = 1
(Falling or
Rising VPWR)
UV fault
is latched
Typical value; not guaranteed
While VDD remains within specified range.
= IN is equivalent to IN direct input or IN_spi SPI input.
LOGIC COMMANDS AND REGISTERS
SPI PROTOCOL DESCRIPTION
The SPI interface has a full duplex, three-wire synchronous data transfer with four I/O lines associated with it: Serial Clock (SCLK), Serial
Input (SI), Serial Output (SO), and Chip Select (CS). The SI / SO pins of the 33984 follow a first-in first-out (D7/ D0) protocol with both input
and output words transferring the most significant bit (MSB) first. All inputs are compatible with 5.0 V CMOS logic levels. The SPI lines
perform the following functions:
SERIAL CLOCK (SCLK)
Serial clocks (SCLK) the internal shift registers of the 33984 device. The serial input (SI) pin accepts data into the input shift register on
the falling edge of the SCLK signal while the serial output (SO) pin shifts data information out of the SO line driver on the rising edge of
the SCLK signal. It is important the SCLK pin be in a logic low state whenever CS makes any transition. For this reason, it is recommended
the SCLK pin be in a logic [0] state whenever the device is not accessed (CS logic [1] state). SCLK has an active internal pull-down, IDWN.
When CS is logic [1], signals at the SCLK and SI pins are ignored and SO is tri-stated (high-impedance). See Figure 9 and Figure 10.
SERIAL INPUT (SI)
This is a serial interface (SI) command data input pin. SI instruction is read on the falling edge of SCLK. An 8-bit stream of serial data is
required on the SI pin, starting with D7 to D0. The internal registers of the 33984 are configured and controlled using a 4-bit addressing
scheme, as shown in Table 9. Register addressing and configuration are described in Table 10. The SI input has an active internal pulldown, IDWN.
SERIAL OUTPUT (SO)
The SO data pin is a tri-stateable output from the shift register. The SO pin remains in a high-impedance state until the CS pin is put into
a logic [0] state. The SO data is capable of reporting the status of the output, the device configuration, and the state of the key inputs. The
SO pin changes states on the rising edge of SCLK and reads out on the falling edge of SCLK. Fault and Input Status descriptions are
provided in Table 6.
CHIP SELECT (CS)
The CS pin enables communication with the master microcontroller (MCU). When this pin is in a logic [0] state, the device is capable of
transferring information to, and receiving information from, the MCU. The 33984 device latches in data from the Input shift registers to the
addressed registers on the rising edge of CS. The device transfers status information from the power output to the shift register on the
falling edge of CS. The SO output driver is enabled when CS is logic [0]. CS should transition from a logic [1] to a logic [0] state only when
SCLK is a logic [0]. CS has an active internal pull-up, IUP.
33984
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Analog Integrated Circuit Device Data
Freescale Semiconductor
FUNCTIONAL DEVICE OPERATION
LOGIC COMMANDS AND REGISTERS
CSB
CS
SCLK
SI
SO
SO
NOTES:
1.
D7
OD7
D6
D5
OD6
D4
OD5
D3
OD4
D2
OD3
D1
OD2
OD1
D0
OD0
RST is in a logic 1 state during the above operation.
RSTB
2. 1.
D0,RST
D1, is
D2,a ...,
and[1]
D7state
relate during
to the most
entry of data into the SPSS
logic
the recent
aboveordered
operation.
Notes
3. OD0, OD1, OD2, ..., and OD7 relate to the first 8 bits of ordered fault and status data out
2. D7:D0 relate to the most recent ordered entry of data into the device.
of the device.
3. OD7:OD0 relate to the first 8 bits of ordered fault and status data out of the device.
Figure 9. Single 8-Bit Word SPI Communication
C S B
CS
S C L K
SCLK
SI
S I
S O
D 7
O D 7
D 6
D 5
O D 6
D 2
O D 5
O D 2
D 1
O D 1
D 0
O D 0
D 7 *
D 7
D 6 *
D 6
D 5 *
D 5
D 2 *
D 2
D 1 *
D 1
D 0 *
D 0
SO
1 .
S T B is in a lo g ic 1 s t a t e d u r in g t h e a b o v e o p e r a t io n .
N O T E S :
Notes
1. RST
is aRD logic
[1] state during the above operation.
2 .
0 , D 1 , D 2 , ..., a n d D 7 r e la te to th e m o s t r e c e n t o r d e r e d e n tr y o f d a t a in to th e S P S S
3 .
O D 0 , O D 1 , O D 2 , . . ., a n d O D 7 r e la t e t o t h e f ir s t 8 b its o f o r d e r e d f a u lt a n d s t a t u s d a t a o u t o f t h e d e v ic e .
2. D7:D0
relate
to the most recent ordered entry of data into the device.
4R.S T O D 0 , O D 1 , O D 2 , . . . , a n d O D 7 r e p r e s e n t t h e f i r s t 8 b i t s o f o r d e r e d f a u l t a n d s t a t u s d a t a o u t o f t h e S P S S
3. D7*:D0* relate to the previous 8 bits (last command word) of data was previously shifted into the device.
4. OD7:OD0 relate to the firstF8I Gbits
of ordered fault and status data out of the device.
U R E 4 b . M U L T IP L E 8 b it W O R D S P I C O M M U N IC A T IO N
Figure 10. Multiple 8-Bit Word SPI Communication
SERIAL INPUT COMMUNICATION
SPI communication is accomplished using 8-bit messages. A message is transmitted by the MCU starting with the MSB, D7, and ending
with the LSB, D0 (Table 9). Each incoming command message on the SI pin can be interpreted using the following bit assignments: the
MSB (D7) is the watchdog bit and in some cases a register address bit common to both outputs or specific to an output; the next three
bits, D6 : D4, are used to select the command register; and the remaining four bits, D3 : D0, are used to configure and control the outputs
and their protection features.
Multiple messages can be transmitted in succession to accommodate those applications where daisy chaining is desirable, or to confirm
transmitted data, as long as the messages are all multiples of eight bits. Any attempt made to latch in a message is not eight bits is ignored.
The 33984 has defined registers, which are used to configure the device and to control the state of the output. Table 10, summarizes the
SI registers. The registers are addressed via D6 : D4 of the incoming SPI word (Table 9).
Table 9. SI Message Bit Assignment
Bit Sig
SI Msg Bit
MSB
D7
LSB
Message Bit Description
Register address bit for output selection. Also used for
watchdog: toggled to satisfy watchdog requirements.
D6 : D4
Register address bits.
D3 : D1
Used to configure the inputs, outputs, and the device protection
features and SO status content.
D0
Used to configure the inputs, outputs, and the device protection
features and SO status content.
33984
Analog Integrated Circuit Device Data
Freescale Semiconductor
23
FUNCTIONAL DEVICE OPERATION
LOGIC COMMANDS AND REGISTERS
Table 10. Serial Input Address and Configuration Bit Map
Serial Input Data
SI Register
D7
D6
D5
D4
D3
D2
D1
D0
STATR
s
0
0
0
0
SOA2
SOA1
SOA0
OCR
x
0
0
1
CSNS1 EN
IN1_SPI
CSNS0 EN
IN0_SPI
SOCHLR
s
0
1
0
SOCHs
SOCL2s
SOCL1s
SOCL0s
CDTOLR
s
0
1
1
OL_DIS s
CD_DIS s
OCLT1s
OCLT0 s
DICR
s
1
0
0
FAST SR s
CSNS
high s
IN DIS s
A/Os
OSDR
0
1
0
1
0
OSD2
OSD1
OSD0
WDR
1
1
0
1
0
0
WD1
WD0
NAR
0
1
1
0
0
0
0
0
UOVR
1
1
1
0
0
0
UV_dis
OV_dis
TEST
x
1
1
1
Freescale Internal Use (Test)
x = Don’t care.
s (SOA3 bit) = Selection of output: logic [0] = HS0, logic [1] = HS1.
DEVICE REGISTER ADDRESSING
The following section describes the possible register addresses and their impact on device operation.
Address x000 — Status Register (STATR)
The STATR register is used to read the device status and the various configuration register contents without disrupting the device
operation or the register contents. The register bits D2:D0, determine the content of the first eight bits of SO data. When register content
is specific to one of the two outputs, bit D7 is used to select the desired output (SOA3). In addition to the device status, this feature provides
the ability to read the content of the OCR, SOCHLR, CDTOLR, DICR, OSDR, WDR, NAR, and UOVR registers. (Refer to the section
entitled Serial Output Communication (Device Status Return Data)).
Address x001 — Output Control Register (OCR)
The OCR register allows the MCU to control the outputs through the SPI. Incoming message bit D0 reflects the desired states of the highside output HS0 (IN0_SPI): a logic [1] enables the output switch and a logic [0] turns it OFF. A logic [1] on message bit D1 enables the
Current Sense (CSNS) pin. Similarly, incoming message bit D2 reflects the desired states of the high-side output HS1 (IN1_SPI): logic [1]
enables the output switch and a logic [0] turns it OFF. A logic [1] on message bit D3 enables the CSNS pin. In the event the current sense
is enabled for both outputs, the current is summed. Bit D7 is used to feed the watchdog if enabled.
Address x010— Select Overcurrent High and Low Register (SOCHLR)
The SOCHLR register allows the MCU to configure the output overcurrent low and high detection levels, respectively. Each output is
independently selected for configuration based on the state of the D7 bit; a write to this register when D7 is logic [0] configures the current
detection levels for the HS0. Similarly, if D7 is logic [1] when this register is written, HS1 is configured. Each output can be configured to
different levels. In addition to protecting the device, this slow blow fuse emulation feature can be used to optimize the load requirements
matching system characteristics. Bits D2 : D0 set the overcurrent low detection level to one of eight possible levels, as shown in Table 11.
Bit D3 sets the overcurrent high detection level to one of two levels, which is described inTable 12.
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Analog Integrated Circuit Device Data
Freescale Semiconductor
FUNCTIONAL DEVICE OPERATION
LOGIC COMMANDS AND REGISTERS
Table 11. Overcurrent Low Detection Levels
SOCL2 (D2)
SOCL1 (D1)
SOCL0 (D0)
Overcurrent Low Detection (Amperes)
0
0
0
25
0
0
1
22.5
0
1
0
20
0
1
1
17.5
1
0
0
15
1
0
1
12.5
1
1
0
10
1
1
1
7.5
Table 12. Overcurrent High Detection Levels
SOCH (D3)
Overcurrent High Detection (Amperes)
0
100
1
75
Address x011 — Current Detection Time and Open Load Register (CDTOLR)
The CDTOLR register is used by the MCU to determine the amount of time the device allows an overcurrent low condition before output
latches OFF occurs. Each output is independently selected for configuration based on the state of the D7 bit. A write to this register when
bit 7 is logic [0] configures the timeout for the HS0. Similarly, if D7 is logic [1] when this register is written, then HS1 is configured. Bits
D1: D0 allow the MCU to select one of four fault blanking times defined in Table 13. Note that these timeouts apply only to the overcurrent
low detection levels. If the selected overcurrent high level is reached, the device latches off within 20 s.
Table 13. Overcurrent Low Detection Blanking Time
OCLT [1:0]
Timing
00
155 ms
01
10 ms
10
1.2 ms
11
150 s
A logic [1] on bit D2 disables the overcurrent low (CD_dis) detection timeout feature. A logic [1] on bit D3 disables the open load (OL)
detection feature.
Address x100 — Direct Input Control Register (DICR)
The DICR register is used by the MCU to enable, disable, or configure the direct IN pin control of each output. Each output is independently
selected for configuration based on the state of bit D7. A write to this register when bit D7 is logic [0] configures the direct input control for
the HS0. Similarly, if D7 is logic [1] when this register is written, then HS1 is configured.
A logic [0] on bit D1 enables the output for direct control by the IN pin. A logic [1] on bit D1 disables the output from direct control. While
addressing this register, if the input was enabled for direct control, a logic [1] for the D0 bit results in a Boolean AND of the IN pin with its
corresponding D0 message bit when addressing the OCR register. Similarly, a logic [0] on the D0 pin results in a Boolean OR of the IN
pin with the corresponding message bits when addressing the OCR register.
The DICR register is useful if there is a need to independently turn on and off several loads are PWMed at the same frequency and duty
cycle with only one PWM signal. This type of operation can be accomplished by connecting the pertinent direct IN pins of several devices
to a PWM output port from the MCU and configuring each of the outputs to be controlled via their respective direct IN pin. The DICR is
then used to Boolean AND the direct IN(s) of each of the outputs with the dedicated SPI bit also controls the output. Each configured SPI
bit can now be used to enable and disable the common PWM signal from controlling its assigned output.
A logic [1] on bit D2 is used to select the high ratio (CSR1, 1/41000) on the CSNS pin for the selected output. The default value [0] is used
to select the low ratio (CSR0,1/20500). A logic [1] on bit D3 is used to select the high speed slew rate for the selected output. The default
value [0] corresponds to the low speed slew rate.
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Analog Integrated Circuit Device Data
Freescale Semiconductor
25
FUNCTIONAL DEVICE OPERATION
LOGIC COMMANDS AND REGISTERS
Address 0101 — Output Switching Delay Register (OSDR)
The OSDR register configures the device with a programmable time delay active during Output ON transitions initiated via the SPI (not
via direct input).
A write to this register configures both outputs for different delay. Whenever the input is commanded to transition from logic [0] to logic [1],
both outputs are held OFF for the time delay configured in the OSDR. The programming of the contents of this register have no effect on
device Fail-safe Mode operation. The default value of the OSDR register is 000, equating to no delay. This feature allows the user a way
to minimize inrush currents, or surges, thereby allowing loads to be switched ON with a single command. There are eight selectable output
switching delay times ranging from 0 ms to 525 ms. Refer to Table 14.
Table 14. Switching Delay
OSD [2:0] (D2 : D0)
Turn ON Delay (ms) HS0
Turn ON Delay (ms) HS1
000
0
0
001
0
75
010
150
150
011
150
225
100
300
300
101
300
375
110
450
450
111
450
525
Address 1101 — Watchdog Register (WDR)
The WDR register is used by the MCU to configure the watchdog timeout. Watchdog timeout is configured using bits D1:D0. When D1:D0
bits are programmed for the desired watchdog timeout period, the WD bit (D7) should be toggled as well, ensuring the new timeout period
is programmed at the beginning of a new count sequence. Refer to Table 15.
Table 15. Watchdog Timeout
WD [1:0] (D1: D0)
Timing (ms)
00
620
01
310
10
2500
11
1250
Address 0110 — No Action Register (NAR)
The NAR register can be used to no-operation fill SPI data packets in a daisy chain SPI configuration. This allows devices to not be affected
by commands being clocked over a daisy chained SPI configuration, and by toggling the WD bit (D7), the watchdog circuitry continues to
be reset while no programming or data readback functions are being requested from the device.
Address 1110 — Undervoltage/Overvoltage Register (UOVR)
The UOVR register can be used to disable or enable overvoltage and/or undervoltage protection. By default (logic [0]), both protections
are active. When disabled, an undervoltage or overvoltage condition fault is not reported in the output fault register.
Address x111 — TEST
The TEST register is reserved for test and is not accessible with SPI during normal operation.
SERIAL OUTPUT COMMUNICATION (DEVICE STATUS RETURN DATA)
When the CS pin is pulled low, the output status register is loaded. Meanwhile, the data is clocked out MSB- (OD7-) first as the new
message data is clocked into the SI pin. The first eight bits of data clocking out of the SO, and following a CS transition, are dependant
upon the previously written SPI word.
Any bits clocked out of the SO pin after the first eight is representative of the initial message bits clocked into the SI pin since the CS pin
first transitioned to a logic [0]. This feature is useful for daisy chaining devices as well as message verification.
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Analog Integrated Circuit Device Data
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FUNCTIONAL DEVICE OPERATION
LOGIC COMMANDS AND REGISTERS
A valid message length is determined following a CS transition of logic [0] to logic [1]. If there is a valid message length, the data is latched
into the appropriate registers. A valid message length is a multiple of eight bits. At this time, the SO pin is tri-stated and the fault status
register is now able to accept new fault status information.
The output status register correctly reflects the status of the STATR-selected register data at the time the CS is pulled to a logic [0] during
SPI communication and / or for the period of time since the last valid SPI communication, with the following exceptions:
• The previous SPI communication was determined to be invalid. In this case, the status is reported as though the invalid SPI
communication never occurred.
• Battery transients below 6.0 V resulting in an undervoltage shutdown of the outputs may result in incorrect data loaded into the status
register. The SO data transmitted to the MCU during the first SPI communication following an undervoltage VPWR condition should
be ignored.
• The RST pin transition from a logic [0] to logic [1] while the WAKE pin is at logic [0] may result in incorrect data loaded into the status
register. The SO data transmitted to the MCU during the first SPI communication following this condition should be ignored.
SERIAL OUTPUT BIT ASSIGNMENT
The 8 bits of serial output data depend on the previous serial input message, as explained in the following paragraphs. Table 16
summarizes the SO register content.
Bit OD7 reflects the state of the watchdog bit (D7) addressed during the prior communication. The value of the previous D7 determines
which output the status information applies to for the Fault (FLTR), SOCHLR, CDTOLR, and DICR registers. SO data represents
information ranging from fault status to register contents, user selected by writing to the STATR bits D2:D0. Note that the SO data
continues to reflect the information for each output (depending on the previous D7 state) was selected during the most recent STATR
write until changed with an updated STATR write.
Previous Address SOA[2:0] = 000
If the previous three MSBs are 000, bits OD6 : OD0 reflects the current state of the Fault register (FLTR) corresponding to the output
previously selected with the bit OD7 (Table 17).
Previous Address SOA[2:0] = 001
Data in bits OD1:OD0 contain CSNS0 EN and IN0_SPI programmed bits, respectively. Data in bits OD3:OD2 contain CSNS0 EN and
IN0_SPI programmed bits, respectively.
Previous Address SOA[2:0] = 010
The data in bit OD3 contain the programmed overcurrent high detection level (refer to Table 12), and the data in bits OD2:OD0 contain
the programmed overcurrent low detection levels (refer to Table 13).
Table 16. Serial Output Bit Map Description
Previous STATR
D7, D2, D1, D0
Serial Output Returned Data
SOA3 SOA2 SOA1 SOA0
OD7
OD6
OD5
OD4
OD3
OD2
OD1
OD0
s
0
0
0
s
OTFs
OCHFs
OCLFs
OLFs
UVF
OVF
FAULT
x
0
0
1
x
0
0
1
CSNS1 EN
IN1_SPI
CSNS0 EN
IN0_SPI
s
0
1
0
s
0
1
0
SOCHs
SOCL2s
SOCL1s
SOCL0s
s
0
1
1
s
0
1
1
OL_DIS s
CD_DIS s
OCLT1s
OCLT0s
s
1
0
0
s
1
0
0
FAST SR s
CSNS High s
IN DIS s
A/O s
0
1
0
1
0
1
0
1
FSM_HS0
OSD2
OSD1
OSD0
1
1
0
1
1
1
0
1
FSM_HS1
WDTO
WD1
WD0
0
1
1
0
0
1
1
0
IN1 Pin
IN0 Pin
FSI Pin
WAKE Pin
1
1
1
0
1
1
1
0
–
–
UV_dis
OV_dis
x
1
1
1
–
–
–
–
See Table 2
–
–
–
s = Selection of output: Logic [0] = HS0, Logic [1] = HS1.
x = Don’t care.
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Analog Integrated Circuit Device Data
Freescale Semiconductor
27
FUNCTIONAL DEVICE OPERATION
LOGIC COMMANDS AND REGISTERS
Table 17. Fault Register
OD7
OD6
OD5
OD4
OD3
OD2
OD1
OD0
s
OTF
OCHFs
OCLFs
OLFs
UVF
OVF
FAULT
OD7 (s) = Selection of Output: Logic [0] = HS0, Logic [1] = HS1.
OD6 (OTF) = Overtemperature Flag.
OD5 (OCHFs) = Overcurrent High Flag. (This fault is latched.)
OD4 (OCLFs) = Overcurrent Low Flag. (This fault is latched.)
OD3 (OLFs) = Open Load Flag.
OD2 (UVF) = Undervoltage Flag. (This fault is latched or not latched.)
OD1 (OVF) = Overvoltage Flag.
OD0 (FAULT) = This flag reports a fault and is reset by a read operation.
FAULT report of any fault on HS0 or HS1
Note The FS pin reports a fault. For latched faults, this pin is reset by a new Switch ON
command (via SPI or direct input IN).
Previous Address SOA[2:0] = 011
Data returned in bits OD1 and OD0 are current values for the overcurrent fault blanking time, illustrated in Table 13. Bit OD2 reports if the
overcurrent detection timeout feature is active. OD3 reports if the open load circuitry is active.
Previous Address SOA[2:0] =100
The returned data contain the programmed values in the DICR.
Previous Address SOA[2:0] = 101
• SOA3 = 0. The returned data contain the programmed values in the OSDR. Bit OD3 (FSM_HS0) reflects the state of the output HS0
in the Fail-safe mode after a watchdog timeout occurs.
• SOA3 = 1. The returned data contain the programmed values in the WDR. Bit OD2 (WDTO) reflects the status of the watchdog
circuitry. If WDTO bit is logic [1], the watchdog has timed out and the device is in Fail-safe mode. If WDTO is logic [0], the device is
in Normal mode (assuming the device is powered and not in Sleep mode), with the watchdog either enabled or disabled. Bit OD3
(FSM_HS1) reflects the state of the output HS1 in the Fail-safe mode after a watchdog timeout occurs.
Previous Address SOA[2:0] = 110
• SOA3 = 0. OD3:OD0 return the state of the IN1, IN0, FSI, and WAKE pins, respectively (Table 18).
Table 18. Pin Register
OD3
OD2
OD1
OD0
IN1 Pin
IN0 Pin
FSI Pin
WAKE Pin
• SOA3 = 1. The returned data contain the programmed values in the UOVR. Bit OD1 reflects the state of the undervoltage protection
and bit OD0 reflects the state of the overvoltage protection. Refer to Table 16).
Previous Address SOA[2:0] =111
Null Data. No previous register Read Back command received, so bits OD2:OD0 are null, or 000.
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TYPICAL APPLICATIONS
TYPICAL APPLICATIONS
VPWR
VDD
Voltage
Regulator
VDD
VDD NC VPWR
VDD
VPWR
33984
2.2 k
10 k
MCU
10
100 nF
10 µF
2
I/O
I/O
SCLK
CS
I/O
SI
SO
I/O
A/D
10 k
4
10 k
12
10 k
10 k
8
10 k
7
3
11
10 k
9
5
1
6
1k
VDD
WAKE
IN0
IN1
SCLK
CS
RST
SO
SI
FS
CSNS
FSI
VPWR
14
HS1
15
HS0
2.5 µF
10 nF
16
LOAD
GND
LOAD
13
RFSI
Figure 11. Typical Applications
The loads must be chosen in order to guarantee the device normal operating conditions for junction temperatures from -40 °C to 150 °C.
In case of permanent short-circuit conditions, the duration and number of activation cycles must be limited with a dedicated MCU fault
management, using the fault reporting through the SPI. When driving DC motor or solenoid loads demanding multiple switching, an
external recirculation device must be used to maintain the device in its safe operating area.
Two application notes are available:
• AN3274, which proposes safe configurations of the eXtreme switch devices in case of application faults, and to protect all circuitry with
minimum external components.
• AN2469, which provides guidelines for printed circuit board (PCB) design and assembly.
Development effort is required by the end users to optimize the board design and PCB layout, in order to reach electromagnetic
compatibility standards (emission and immunity).
33984
Analog Integrated Circuit Device Data
Freescale Semiconductor
29
TYPICAL APPLICATIONS
OUTPUT CURRENT MONITORING
OUTPUT CURRENT MONITORING
This section relates to the output current monitoring for 33984, Dual 4.0 m High-side Switch. This device is a self-protected silicon switch
used to replace electromechanical relays, fuses, and discrete circuits in power management applications. The MC33984 features a current
recopy which is proportional to the load current. It can be configured between two ratios via the SPI (CSR0 and CSR1).
This section presents the current recopy tolerance of the device and the improvement of this feature with the calibration practice.
CURRENT RECOPY TOLERANCE
The Current Sense Ratio Accuracies described in Current Sense Ratio (CSR0) Accuracy (CSR0_ACC and CSR1_ACC) take into account:
• part to part deviation due to manufacturing,
• ambient temperature derating (from -40 °C to 125 °C),
• battery voltage range (from 9.0 V to 16 V).
Thanks to statistical data analysis performed on 3 production lots (initial testing only), the effect of each contributor has been
demonstrated. Figure 12 shows the CSR0 tolerance in function to three previous listed contributors in comparison to the minimum and
maximum specified values.
Current Recopy at Vbat=9V/16V from -40°C to
125°C
24000
Spec_max
CSNS ratio (CSR0)
23000
Max(Data_9V) at 6 sigmas
22000
Max(Data_16V) at 6 sigmas
10%
21000
Average (Data)
20000
Min(Data_16V) at 6 sigmas
19000
Min(Data_9V) at 6 sigmas
18000
Spec_min
17000
16000
10
15
20
Output current (A)
25
Figure 12. CSR0 Ratio Deviation in Function All Contributors
Lower VPWR Voltage causes more error. 9.0 V corresponding to the worst case. Figure 13 shows the CSR0 tolerance without battery
variation effect.
Current Recopy at Vbat=9V from -40°C to 125°C
24000
CSNS ratio (CSR0)
23000
22000
21000
20000
19000
18000
17000
16000
10
15
20
Output current (A)
25
Figure 13. CSR0 Ratio Deviation in Function Manufacturing and Temperature
33984
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Analog Integrated Circuit Device Data
Freescale Semiconductor
TYPICAL APPLICATIONS
OUTPUT CURRENT MONITORING
The main contributor is the manufacturing deviation, as described in Figure 14. At 15 A of output current, the tolerance is about 8.5%
versus 10% when all contributors are considered.
Current Recopy at Vbat=9V at 25°C
24000
Spec_max
23000
CSNS ratio (CSR0)
Max(Data) at 6 sigmas
22000
8.5%
21000
Average (Data)
20000
19000
Min(Data) at 6 sigmas
18000
Spec_min
17000
16000
10
15
20
25
Output current (A)
Figure 14. CSR0 Ratio Deviation in Function Manufacturing
PART CALIBRATION
With a calibration strategy, the part to part contribution can be removed. An experiment was done on low output current values (below
5.0 A). The relative CSR0 deviation based on only one calibration point per output (5.0 A, VPWR =16 V at 25°C) has been performed on
three production lots. Those parts have tested at initial and after high temperature operating Life test in order to take into account the
ageing of devices. Table 19 summaries test results covering 99.74% of parts.
Table 19. CSR0 Precision for Several Output Current Values with One Calibration Point at 5.0 A
CSR0 ratio
Min
Max
0.5 A
-25%
25%
1.0 A
-12%
12%
2.5 A
-8.0%
8.0%
5.0 A
-5.0%
5.0%
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Analog Integrated Circuit Device Data
Freescale Semiconductor
31
PACKAGING
SOLDERING INFORMATION
PACKAGING
SOLDERING INFORMATION
SOLDERING INFORMATION
The 33984 is packaged in a surface mount power package (PQFN), intended to be soldered directly on the printed circuit board.
The AN2467 provides guidelines for Printed Circuit Board design and assembly.
PACKAGE DIMENSIONS
For the most current revision of the package, visit www.freescale.com and perform a keyword search on 98ARL10521D. Dimensions
shown are provided for reference ONLY.
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Analog Integrated Circuit Device Data
Freescale Semiconductor
PACKAGING
PACKAGE DIMENSIONS
33984
Analog Integrated Circuit Device Data
Freescale Semiconductor
33
ADDITIONAL DOCUMENTATION
THERMAL ADDENDUM (REV 3.0)
ADDITIONAL DOCUMENTATION
33984
THERMAL ADDENDUM (REV 3.0)
Introduction
This thermal addendum is provided as a supplement to the 33984 technical datasheet. The
addendum provides thermal performance information which may be critical in the design
and development of system applications. All electrical, application, and packaging
information is provided in the datasheet.
HIGH-SIDE SWITCH
Packaging and Thermal Considerations
This package is a dual die package. There are two heat sources in the package
independently heating with P1 and P2. This results in two junction temperatures, TJ1 and
TJ2, and a thermal resistance matrix with RJAmn.
For m, n = 1, RJA11 is the thermal resistance from Junction 1 to the reference temperature
while only heat source 1 is heating with P1.
For m = 1, n = 2, RJA12 is the thermal resistance from Junction 1 to the reference
temperature while heat source 2 is heating with P2. This applies to RJ21 and RJ22,
respectively.
TJ1
TJ2
=
RJA11 RJA12
.
RJA21 RJA22
P1
P2
98ARL10521D
16-PIN PQFN
12 mm x 12 mm
Note For package dimensions, refer to
98ARL10521D.
The stated values are solely for a thermal performance comparison of one package to another in a standardized environment. This
methodology is not meant to and does not predict the performance of a package in an application-specific environment. Stated values
were obtained by measurement and simulation according to the standards listed below.
Standards
Table 20. Thermal Performance Comparison
1 = Power Chip, 2 = Logic Chip [C/W]
Thermal
Resistance
m = 1,
n=1
m = 1, n = 2
m = 2, n = 1
m = 2,
n=2
RJAmn(1) (2)
20
16
39
RJBmn(2) (3)
6.0
2.0
26
RJAmn(1) (4)
53
40
72
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