MC33993DWB [MOTOROLA]

Multiple Switch Detection Interface; 多开关检测接口
MC33993DWB
型号: MC33993DWB
厂家: MOTOROLA    MOTOROLA
描述:

Multiple Switch Detection Interface
多开关检测接口

驱动程序和接口 开关 接口集成电路 光电二极管
文件: 总28页 (文件大小:800K)
中文:  中文翻译
下载:  下载PDF数据表文档文件
MOTOROLA  
Document order number: MC33993/D  
Rev 2.0, 07/2003  
SEMICONDUCTOR TECHNICAL DATA  
Advance Information  
33993  
Multiple Switch Detection Interface  
The 33993 Multiple Switch Detection Interface is designed to detect the  
closing and opening of up to 22 switch contacts. The switch status, either open  
or closed, is transferred to the microprocessor unit (MCU) through a serial  
peripheral interface (SPI). The device also features a 22-to-1 analog multiplexer  
for reading inputs as analog. The analog input signal is buffered and provided on  
the AMUX output pin for the MCU to read.  
MULTIPLE SWITCH  
DETECTION INTERFACE  
The 33993 device has two modes of operation, Sleep and Normal. The Sleep  
mode provides low quiescent current and enables the wake-up features of the  
device. Normal mode allows programming of the device and supplies switch  
contacts with pull-up or pull-down current as it monitors switch change of state.  
The 33993 is packaged in the 32-pin wide-body SOIC, reducing circuit board  
area. Low quiescent current makes the 33993 ideal for automotive and industrial  
products requiring low sleep state currents. The internal block diagram of the  
33993 is illustrated in Figure 1, page 2.  
Features  
DWB SUFFIX  
CASE 1324  
• Designed to Operate 5.5 V VPWR 26 V  
• Switch Input Voltage Range -14 V to VPWR, 40 V Max  
32-LEAD SOICW  
• Interfaces Directly to Microprocessor Using 3.3 V/5.0 V SPI Protocol  
• Selectable Wake-Up on Change of State  
ORDERING INFORMATION  
Temperature  
• Selectable Wetting Current (16 mA or 2.0 mA)  
Device  
Package  
• 8 Programmable Inputs (Switches to Battery or Ground)  
• 14 Switch-to-Ground Inputs  
• VPWR Standby Current 100 µA Typical, VDD Standby Current 20 µA Typical  
Range (T )  
A
MC33993DWB/R2  
32 SOICW  
-40°C to 125°C  
• Active Interrupt (INT) on Change-of-Switch State  
33993 Simplified Application Diagram  
VDD  
Power Supply  
LVI  
VBAT  
VBAT  
33993  
MCU  
Enable  
Watchdog  
Reset  
SP0  
SP1  
VPWR  
VDD  
VBAT  
VDD  
SP7  
WAKE  
SI  
MOSI  
SCLK  
CS  
MISO  
INT  
SCLK  
CS  
SG0  
SG1  
SO  
INT  
AMUX  
AN0  
SG12  
SG13  
GND  
This document contains certain information on a new product.  
Specifications and information herein are subject to change without notice.  
© Motorola, Inc. 2003  
5.0 V  
VPWR  
VPWR VPWR  
SP0  
VPWR, VDD, 5.0 V  
VPWR  
VDD  
GND  
16.0  
2.0  
mA  
POR  
mA  
Bandgap  
Sleep PWR  
SP0  
SP1  
SP2  
SP3  
SP4  
SP5  
SP6  
SP7  
To  
+
4.0 V  
Ref  
2.0  
mA  
16.0  
mA  
SPI  
Comparator  
VPWR VPWR  
SP7  
16.0  
mA  
2.0  
mA  
5.0 V  
VPWR  
Oscillator  
and  
To  
Clock Control  
+
4.0 V  
Ref  
2.0  
mA  
16.0  
mA  
SPI  
Comparator  
5.0 V  
Temperature  
Monitor and  
Control  
5.0 V  
VPWR  
VPWR VPWR  
SG0  
5.0 V  
125 kΩ  
16.0  
mA  
2.0  
mA  
5.0 V  
SG0  
SG1  
SG2  
SG3  
SG4  
SG5  
SG6  
SG7  
SG8  
SG9  
SG10  
SG11  
SG12  
SG13  
WAKE  
INT  
To  
+
4.0 V  
Ref  
SPI  
WAKE Control  
Comparator  
VDD  
125 kΩ  
SPI Interface  
and Control  
INT Control  
VDD  
MUX Interface  
40 µA  
CS  
SCLK  
SI  
V
DD  
SO  
VPWR VPWR  
SG13  
16.0  
mA  
2.0  
mA  
VDD  
Analog Mux  
Output  
+
AMUX  
To  
+
4.0 V  
Ref  
SPI  
Comparator  
Figure 1. 33993 Simplified Internal Block Diagram  
33993/D  
MOTOROLA ANALOG INTEGRATED CIRCUIT DEVICE DATA  
2
GND  
SI  
SO  
1
2
3
4
5
6
7
8
32  
31  
30  
29  
28  
27  
26  
25  
24  
23  
22  
21  
20  
19  
18  
17  
VDD  
SCLK  
CS  
AMUX  
INT  
SP0  
SP1  
SP2  
SP3  
SG0  
SG1  
SG2  
SG3  
SG4  
SG5  
SG6  
VPWR  
SP7  
SP6  
SP5  
SP4  
9
SG7  
SG8  
SG9  
SG10  
SG11  
SG12  
SG13  
WAKE  
10  
11  
12  
13  
14  
15  
16  
PIN FUNCTIONAL DESCRIPTION  
Pin  
1
Pin Name  
GND  
SI  
Formal Name  
Description  
Ground  
Ground for logic, analog, and switch to battery inputs.  
SPI control data input pin from MCU to 33993.  
SPI control clock input pin.  
2
SPI Slave In  
Serial Clock  
Chip Select  
3
SCLK  
CS  
4
SPI control chip select input pin from MCU to 33993. Logic 0 allows data to be  
transferred in.  
5–8  
25–28  
SP0–3  
SP4–7  
Programmable Switches 0–7  
Programmable switch-to-battery or switch-to-ground input pins.  
9–15,  
18–24  
SG0–6,  
SG13–7  
Switch-to-Ground Inputs 0–13 Switch-to-ground input pins.  
16  
V
Battery Input  
Battery supply input pin. Pin requires external reverse battery protection.  
PWR  
17  
29  
30  
31  
Wake-Up  
Interrupt  
Open drain wake-up output. Designed to control a power supply enable pin.  
Open-drain output to MCU. Used to indicate input switch change of state.  
Analog multiplex output.  
WAKE  
INT  
AMUX  
Analog Multiplex Output  
Voltage Drain Supply  
V
3.3/5.0 V supply. Sets SPI communication level for SO driver.  
DD  
32  
SO  
SPI Slave Out  
Provides digital data from 33993 to MCU.  
MOTOROLA ANALOG INTEGRATED CIRCUIT DEVICE DATA  
33993/D  
3
MAXIMUM RATINGS  
All voltages are with respect to ground unless otherwise noted.  
Rating  
Symbol  
Value  
Unit  
V
Supply Voltage  
-0.3 to 7.0  
V
V
V
V
V
DD  
DC  
DC  
DC  
DC  
DC  
-0.3 to 7.0  
-0.3 to 40  
-0.3 to 50  
CS, SI, SO, SCLK, INT, AMUX (Note 1)  
WAKE (Note 1)  
V
Supply Voltage (Note 1)  
PWR  
Switch Input Voltage Range  
-14 to 40  
6.0  
Frequency of SPI Operation (VDD = 5.0 V)  
MHz  
V
ESD Voltage (Note 2)  
VESD1  
VESD2  
±4000  
±200  
Human Body Model (Note 3), (Note 4)  
Machine Model (Note 5)  
Storage Temperature  
T
-55 to 150  
-40 to 125  
-40 to 150  
1.7  
°C  
°C  
°C  
W
STG  
Operating Case Temperature  
Operating Junction Temperature  
Power Dissipation (TA = 25°C) (Note 6)  
TC  
TJ  
PD  
Thermal Resistance  
Junction to Ambient  
Junction to Lead  
°C/W  
R
74  
25  
JA  
θ
R
JL  
θ
Notes  
1. Exceeding these limits may cause malfunction or permanent damage to the device.  
2. ESD data available upon request.  
3. ESD1 testing is performed in accordance with the Human Body Model (CZAP = 100 pF, RZAP = 1500 ).  
4. All pins when tested individually.  
5. ESD2 testing is performed in accordance with the Machine Model (CZAP = 200 pF, RZAP = 0 ).  
6. Maximum power dissipation at TJ =150°C junction temperature with no heat sink used.  
33993/D  
4
MOTOROLA ANALOG INTEGRATED CIRCUIT DEVICE DATA  
STATIC ELECTRICAL CHARACTERISTICS  
Characteristics noted under conditions of 3.1 V VDD 5.25 V, 8.0 V VPWR 16 V, -40°C TC 125°C, unless otherwise noted.  
Where applicable, typical values reflect the parameter’s approximate average value with VPWR = 13 V, TA = 25°C.  
Characteristic  
Symbol  
Min  
Typ  
Max  
Unit  
POWER INPUT  
Supply Voltage  
V
Supply Voltage Range Quasi-Functional (Note 7)  
Fully Operational  
Supply Voltage Range Quasi-Functional (Note 7)  
V
V
V
5.5  
8.0  
26  
8.0  
26  
40  
PWR  
(
qf  
)
)
)
(
PWR fo  
PWR  
(
qf  
Supply Current  
I
mA  
PWR  
on  
( )  
All Switches Open, Normal Mode, Tri-State Disabled  
2.0  
4.0  
Sleep State Supply Current  
I
µA  
PWR  
ss  
( )  
Scan Timer = 64 ms, Switches Open  
40  
70  
100  
Logic Supply Voltage  
V
3.1  
5.25  
V
DD  
Logic Supply Current  
I
mA  
DD  
All Switches Open, Normal Mode  
0.25  
10  
0.5  
20  
Sleep State Logic Supply Current  
Scan Timer = 64 ms, Switches Open  
I
µA  
DD  
ss  
( )  
SWITCH INPUT  
Pulse Wetting Current Switch-to-Battery (Current Sink)  
I
I
12  
12  
15  
16  
18  
18  
mA  
mA  
mA  
mA  
%
Pulse  
Pulse  
Pulse Wetting Current Switch-to-Ground (Current Source)  
Sustain Current Switch-to-Battery Input (Current Sink)  
I
I
1.8  
1.8  
2.0  
2.0  
2.2  
2.2  
sustain  
sustain  
Sustain Current Switch-to-Ground Input (Current Source)  
Sustain Current Matching Between Channels on Switch-to-Ground Inputs  
I
Match  
ISUS(MAX)  
I
SUS(MIN)  
ISUS(MIN)  
-
2.0  
1.4  
4.0  
2.0  
X 100  
Input Offset Current when Selected as Analog  
Input Offset Voltage when Selected as Analog  
I
-2.0  
µA  
offset  
V
mV  
offset  
V
(SP&SGinputs) to AMUX Output  
-10  
2.5  
10  
10  
30  
Analog Operational Amplifier Output Voltage  
V
mV  
V
OL  
Sink 250 µA  
Analog Operational Amplifier Output Voltage  
V
OH  
Source 250 µA  
V
- 0.1  
4.0  
DD  
Switch Detection Threshold  
V
3.70  
-14  
4.3  
40  
V
V
th  
in  
Switch Input Voltage Range  
V
Temperature Monitor (Note 8), (Note 9)  
Temperature Monitor Hysteresis (Note 9)  
T
155  
5.0  
185  
15  
°C  
°C  
LIM  
T
10  
LIM(hys  
)
Notes  
7. Device operational. Table parameters may be out of specification.  
8. Thermal shutdown of 16 mA pull-up and pull-down current sources only. 2.0 mA current source/sink and all other functions remain active.  
9. This parameter is guaranteed by design but is not production tested.  
MOTOROLA ANALOG INTEGRATED CIRCUIT DEVICE DATA  
33993/D  
5
STATIC ELECTRICAL CHARACTERISTICS (continued)  
Characteristics noted under conditions of 3.1 V VDD 5.25 V, 8.0 V VPWR 16 V, -40°C TC 125°C, unless otherwise noted.  
Where applicable, typical values reflect the parameter’s approximate average value with VPWR = 13 V, TA = 25°C.  
Characteristic  
Symbol  
Min  
0.8  
-10  
Typ  
Max  
2.2  
10  
Unit  
DIGITAL INTERFACE  
Input Logic Voltage Thresholds (Note 10)  
V
V
INLOGIC  
SCLK, SI, Tri-State SO Input Current  
I
I
µA  
SCLK, SI,  
I
0 V to V  
DD  
SO(Tri)  
µA  
CS Input Current  
I
CS  
CS  
-10  
30  
10  
CS = V  
DD  
µA  
V
CS Pull-Up Current  
CS = 0 V  
I
100  
SO High-State Output Voltage  
V
SO(high)  
I
= -200 µA  
V
V
- 0.8  
V
V
+ 0.3  
DD  
SO(high)  
SO Low-State Output Voltage  
= 1.6 mA  
DD  
V
V
SO(low)  
I
0.4  
SO(high)  
Input Capacitance on SCLK, SI, Tri-State SO (Note 11)  
INT Internal Pull-Up Current  
C
20  
pF  
µA  
V
IN  
20  
40  
100  
INT Voltage  
V
high  
INT( )  
- 0.2  
+ 0.3  
DD  
INT = Open Circuit  
DD  
V
INT Voltage  
V
INT(low)  
0.2  
40  
0.4  
I
= 1.0 mA  
INT  
20  
100  
µA  
WAKE Internal Pull-Up Current  
I
WAKE  
(
pu  
)
V
WAKE Voltage  
V
WAKE  
(
high  
)
4.0  
4.3  
0.2  
5.2  
0.4  
WAKE = Open Circuit  
V
V
WAKE Voltage  
V
WAKE(low)  
WAKE(max)  
I
WAKE = 1.0 mA  
WAKE Voltage  
V
40  
Maximum Voltage Applied to WAKE Through External Pull-Up  
Notes  
10. Upper and lower logic threshold voltage levels apply to SI, CS, and SCLK.  
11. This parameter is guaranteed by design but is not production tested.  
33993/D  
6
MOTOROLA ANALOG INTEGRATED CIRCUIT DEVICE DATA  
DYNAMIC ELECTRICAL CHARACTERISTICS  
Characteristics noted under conditions of 3.1 V VDD 5.25 V, 8.0 V VPWR 16 V, -40°C TC 125°C, unless otherwise noted.  
Where applicable, typical values reflect the parameter’s approximate average value with VPWR = 13 V, TA = 25°C.  
Characteristic  
Symbol  
Min  
Typ  
Max  
Unit  
SWITCH INPUT  
Pulse Wetting Current Time  
t
15  
16  
20  
ms  
pulse  
(
on  
)
Interrupt Delay Time  
Normal Mode  
t
µs  
int-dly  
5.0  
16  
Sleep Mode Switch Scan Time  
t
100  
200  
300  
µs  
scan  
Calibrated Scan Timer Accuracy  
Sleep Mode  
t
%
scan timer  
10  
10  
Calibrated Interrupt Timer Accuracy  
Sleep Mode  
t
%
int timer  
DIGITAL INTERFACE TIMING (Note 12)  
Required Low State Duration on VPWR for Reset (Note 13)  
t
µs  
RESET  
10  
V
PWR 0.2 V  
t
ns  
Falling Edge of CS to Rising Edge of SCLK  
Required Setup Time  
lead  
100  
Falling Edge of SCLK to Rising Edge of CS  
Required Setup Time  
t
ns  
ns  
ns  
lag  
50  
16  
SI to Falling Edge of SCLK  
Required Setup Time  
t
SI(su  
)
Falling Edge of SCLK to SI  
Required Hold Time  
t
SI(hold)  
20  
SI, CS, SCLK Signal Rise Time (Note 14)  
SI, CS, SCLK Signal Fall Time (Note 14)  
t
t
5.0  
5.0  
ns  
ns  
r
f
(SI)  
(SI)  
Time from Falling Edge of CS to SO Low Impedance (Note 15)  
Time from Rising Edge of CS to SO High Impedance (Note 16)  
Time from Rising Edge of SCLK to SO Data Valid (Note 17)  
t
55  
55  
55  
ns  
ns  
ns  
SO(en  
)
t
SO(dis  
)
25  
t
valid  
Notes  
12. These parameters are guaranteed by design. Production test equipment uses 4.16 MHz, 5.0 V SPI interface.  
13. This parameter is guaranteed by design but not production tested.  
14. Rise and Fall time of incoming SI, CS, and SCLK signals suggested for design consideration to prevent the occurrence of double pulsing.  
15. Time required for valid output status data to be available on SO pin.  
16. Time required for output states data to be terminated at SO pin.  
17. Time required to obtain valid data out from SO following the rise of SCLK with 200 pF load.  
MOTOROLA ANALOG INTEGRATED CIRCUIT DEVICE DATA  
33993/D  
7
Timing Diagrams  
CS  
0.2 V  
DD  
t
t
lag  
lead  
0.7 V  
0.2 V  
DD  
SCLK  
DD  
t
t
SI(hold)  
SI(su)  
0.7 V  
0.2 V  
DD  
DD  
SI  
MSB in  
t
t
valid  
SO(en)  
t
SO(dis)  
0.7 V  
0.2 V  
DD  
DD  
SO  
MSB out  
LSB out  
Figure 2. SPI Timing Characteristics  
V
V
PWR  
DD  
WAKE  
INT  
Wake-Up From Interrupt  
Timer Expire  
CS  
Wake-Up From  
Closed Switch  
SGn  
Power-Up  
Normal Mode  
Tri-State  
Sleep  
Command  
Sleep Mode  
Normal  
Mode  
Sleep Command  
Normal  
Mode  
Sleep Command  
Sleep Mode  
Command  
(Disable Tri-State)  
Figure 3. Sleep Mode to Normal Mode Operation  
Switch state change with  
CS low generates INT  
Switch state change with  
CS low generates INT  
INT  
CS  
Latch switch status  
on falling edge of CS  
Rising edge of CS does not  
clear INT because state change  
occurred while CS was low  
SGn  
Switch open “0”  
0
Switch closed “1”  
1
1
0
0
1
SGn Bit in SPI Word  
Switch  
Switch  
Switch  
Switch  
Switch  
Switch  
Status  
Status  
Status  
Status  
Status  
Status  
Command  
Command  
Command  
Command  
Command  
Command  
Figure 4. Normal Mode Interrupt Operation  
33993/D  
8
MOTOROLA ANALOG INTEGRATED CIRCUIT DEVICE DATA  
SYSTEM/APPLICATION INFORMATION  
INTRODUCTION  
The 33993 device is an integrated circuit designed to provide  
switch inputs may be read as analog inputs through the analog  
multiplexer (AMUX). Other features include a programmable  
wake-up timer, programmable interrupt timer, programmable  
wake-up/interrupt bits, and programmable wetting current  
settings.  
systems with ultra-low quiescent sleep/wake-up modes and a  
robust interface between switch contacts and a  
microprocessor. The 33993 replaces many of the discrete  
components required when interfacing to microprocessor-  
based systems while providing switch ground offset protection,  
contact wetting current, and system wake-up.  
This device is designed primarily for automotive applications  
but may be used in a variety of other applications such as  
computer, telecommunications, and industrial controls.  
The 33993 features 8-programmable switch-to-ground or  
switch-to-battery inputs and 14 switch-to-ground inputs. All  
FUNCTIONAL PIN DESCRIPTION  
SI  
CS  
The system MCU selects the 33993 to receive  
The SI pin is used for serial instruction data input. SI  
communication using the chip select (CS) pin. With the CS in a  
logic low state, command words may be sent to the 33993 via  
the serial input (SI) pin, and switch status information can be  
received by the MCU via the serial output (SO) pin. The falling  
edge of CS enables the SO output, latches the state of the INT  
pin, and the state of the external switch inputs.  
information is latched into the input register on the falling edge  
of SCLK. A logic high state present on SI will program a one in  
the command word on the rising edge of the CS signal. To  
program a complete word, 24 bits of information must be  
entered into the device.  
SO  
Rising edge of the CS initiates the following operation:  
1. Disables the SO driver (high impedance)  
The SO pin is the output from the shift register. The SO pin  
remains tri-stated until the CS pin transitions to a logic low state.  
All open switches are reported as zero, all closed switches are  
reported as one. The negative transition of CS enables the SO  
driver.  
2. INT pin is reset to logic [1], except when additional switch  
changes occur during CS low. (See Figure 4 on page 8.)  
3. Activates the received command word, allowing the  
33993 to act upon new data from switch inputs.  
The first positive transition of SCLK will make the status data  
bit 24 available on the SO pin. Each successive positive clock  
will make the next status data bit available for the MCU to read  
on the falling edge of SCLK. The SI/SO shifting of the data  
follows a first-in-first-out protocol, with both input and output  
words transferring the most significant bit (MSB) first.  
To avoid any spurious data, it is essential the high-to-low and  
low-to-high transitions of the CS signal occur only when SCLK  
is in a logic low state. Internal to the 33993 device is an active  
pull-up to VDD on CS.  
In Sleep mode the negative edge of CS (VDD applied) will  
wake up the 33993 device. Data received from the device  
during CS wake-up may not be accurate.  
INT  
The INT pin is an interrupt output from the 33993 device. The  
SCLK  
INT pin is an open-drain output with an internal pull-up to VDD  
.
In Normal mode, a switch state change will trigger the INT pin  
(when enabled). The INT pin and INT bit in the SPI register are  
latched on the falling edge of CS. This permits the MCU to  
determine the origin of the interrupt. When two 33993 devices  
are used, only the device initiating the interrupt will have the  
INT bit set. The INT pin is cleared on the rising edge of CS. The  
INT pin will not clear with rising edge of CS if a switch contact  
change has occurred while CS was low.  
The system clock (SCLK) pin clocks the internal shift register  
of the 33993. The SI data is latched into the input shift register  
on the falling edge of SCLK signal. The SO pin shifts the switch  
status bits out on the rising edge of SCLK. The SO data is  
available for the MCU to read on the falling edge of SCLK. False  
clocking of the shift register must be avoided to ensure validity  
of data. It is essential the SCLK pin be in a logic low state  
whenever CS makes any transition. For this reason, it is  
recommended, though not necessary, that the SCLK pin is  
commanded to a low logic state as long as the device is not  
accessed and CS is in a logic high state. When the CS is in a  
logic high state, any signal on the SCLK and SI pins will be  
ignored and the SO pin is tri-state.  
In a multiple 33993 device system with WAKE high and VDD  
on (Sleep mode), the falling edge of INT will place all 33993s in  
Normal mode.  
MOTOROLA ANALOG INTEGRATED CIRCUIT DEVICE DATA  
33993/D  
9
WAKE  
GND  
The WAKE pin is an open-drain output and a wake-up input.  
The GND pin provides ground for the IC as well as ground for  
The pin is designed to control a power supply Enable pin. In the  
Normal mode, the WAKE pin is low. In the Sleep mode, the  
WAKE pin is high. The WAKE pin has a pull-up to the internal  
+5.0 V supply.  
inputs programmed as switch-to-battery inputs.  
SP0–SP7  
The 33993 device has 8 switch inputs capable of being  
programmed to read switch-to-ground or switch-to-battery  
contacts. The input is compared with a 4.0 V reference. When  
programmed to be switch-to-battery, voltages greater than  
4.0 V are considered closed. Voltages less than 4.0 V are  
considered open. The opposite holds true when inputs are  
programmed as switch-to-ground. Programming features are  
defined in Table 1 through Table 6 in the Device Operation  
section of this datasheet beginning on page 12. Voltages  
greater than the VPWR supply voltage will source current  
In Sleep mode with the WAKE pin high, falling edge of WAKE  
will place the 33993 in Normal mode. In Sleep mode with VDD  
applied, the INT pin must be high for negative edge of WAKE to  
wake up the device. If VDD is not applied to the device in Sleep  
mode, INT does not affect WAKE operation.  
V
PWR  
The VPWR pin is battery input and Power-ON Reset to the  
33993 IC. The VPWR pin requires external reverse battery and  
transient protection. Maximum input voltage on VPWR is 50 V.  
through the SP inputs to the VPWR pin. Transient battery  
voltages greater than 40 V must be clamped by an external  
device.  
All wetting, sustain, and internal logic current is provided from  
the VPWR pin.  
SG0–SG13  
V
DD  
The SGn pins are switch-to-ground inputs only. The input is  
compared with a 4.0 V reference. Voltages greater than 4.0 V  
are considered open. Voltages less than 4.0 V are considered  
closed. Programming features are defined in Table 1 through  
Table 6 in the Device Operation section of this datasheet  
beginning on page 12. Voltages greater than the VPWR supply  
voltage will source current through the SG inputs to the VPWR  
pin. Transient battery voltages greater than 40 V must be  
clamped by an external device.  
The VDD input pin is used to determine logic levels on the  
microprocessor interface (SPI) pins. Current from VDD is used  
to drive SO output and the pull-up current for CS and INT pins.  
VDD must be applied for wake-up from negative edge of CS or  
INT.  
33993/D  
10  
MOTOROLA ANALOG INTEGRATED CIRCUIT DEVICE DATA  
MCU INTERFACE DESCRIPTION  
The 33993 device directly interfaces to a 3.3 V or 5.0 V  
MC68HCXX  
microcontroller unit (MCU). SPI serial clock frequencies up to  
6.0 MHz may be used for programming and reading switch  
input status (production tested at 4.16 MHz). Figure 5 illustrates  
the configuration between an MCU and one 33993.  
Microcontroller  
33993  
33993  
MOSI  
SI  
Shift Register  
MISO  
SCLK  
SO  
SCLK  
CS  
Serial peripheral interface (SPI) data is sent to the 33993  
device through the SI input pin. As data is being clocked into the  
SI pin, status information is being clocked out of the device by  
the SO output pin. The response to a SPI command will always  
return the switch status, interrupt flag, and thermal flag. Input  
switch states are latched into the SO register on the falling edge  
of the chip select (CS) pin. Twenty-four bits are required to  
complete a transfer of information between the 33993 and the  
MCU.  
Parallel  
Ports  
INT  
INT  
SI  
SO  
MC68HCXX  
33993  
SCLK  
Microcontroller  
CS  
MOSI  
MISO  
SI  
INT  
Shift Register  
24-Bit Shift Register  
SO  
Figure 6. SPI Parallel Interface with Microprocessor  
SCLK  
Receive  
Buffer  
To Logic  
MC68HCXX  
Microcontroller  
33993  
CS  
Parallel  
Ports  
MOSI  
INT  
INT  
SI  
Shift Register  
MISO  
SO  
Figure 5. SPI Interface with Microprocessor  
SCLK  
SCLK  
Parallel  
Ports  
CS  
INT  
Two or more 33993 devices may be used in a module  
system. Multiple ICs may be SPI-configured in parallel or serial.  
Figures 6 and 7 show the configurations. When using the serial  
configuration, 48-clock cycles are required to transfer data in/  
out of the ICs.  
INT  
33993  
SI  
SO  
SCLK  
CS  
INT  
Figure 7. SPI Serial Interface with Microprocessor  
MOTOROLA ANALOG INTEGRATED CIRCUIT DEVICE DATA  
33993/D  
11  
DEVICE OPERATION  
Normal Mode  
Power Supply  
Normal mode may be entered by the following events:  
The 33993 is designed to operate from 5.5 V to 40 V on the  
VPWR pin. Characteristics are provided from 8.0 V to 16 V for  
the device. Switch contact currents and the internal logic supply  
are generated from the VPWR pin. The VDD supply pin is used to  
• Application of VPWR to the IC  
• Change-of-Switch State (when enabled)  
• Falling Edge of WAKE  
• Falling Edge of INT (with VDD = 5.0 V and WAKE at  
Logic [1])  
• Falling Edge of CS (with VDD = 5.0 V)  
set the SPI communication voltage levels, current source for the  
SO driver, and pull-up current on INT and CS.  
VDD supply may be removed from the device to reduce  
quiescent current. If VDD is removed while the device is in  
Normal mode, the device will remain in Normal mode. If VDD is  
removed in Sleep mode, the device will remain in Sleep mode  
until wake-up input is received (WAKE high to low, switch input  
or interrupt timer expires).  
• Interrupt Timer Expires  
Only in Normal mode with VDD applied can the registers of the  
33993 be programmed through the SPI.  
The registers that may be programmed in Normal mode are  
listed below. Further explanation of each register is provided in  
subsequent paragraphs.  
Removing VDD from the device disables SPI communication  
and will not allow the device to wake up from INT and CS pins.  
Programmable Switch Register (Settings Command)  
Wake-Up/Interrupt Register (Wake-Up/Interrupt  
Command)  
Wetting Current Register (Metallic Command)  
Wetting Current Timer Register (Wetting Current Timer  
Enable Command)  
Tri-State Register (Tri-State Command)  
Analog Select Register (Analog Command)  
Calibration of Timers (Calibration Command)  
Reset (Reset Command)  
Power-ON Reset (POR)  
Applying VPWR to the device will cause a Power-ON Reset  
and place the device in Normal mode.  
Default settings from Power-ON Reset via VPWR or Reset  
Command are as follows:  
• Programmable Switch – Set to Switch to Battery  
• All Inputs Set as Wake-Up  
• Wetting Current On (16 mA)  
• Wetting Current Timer On (20 ms)  
• All Inputs Tri-State  
Figure 4, page 8, is a graphical description of the device  
operation in Normal mode. Switch states are latched into the  
input register on the falling edge of CS. The INT to the MCU is  
cleared on the rising edge of CS. However, INT will not clear on  
rising edge of CS if a switch has closed during SPI  
communication (CS low). This prevents switch states from  
being missed by the MCU.  
• Analog Select 00000 (No Input Channel Selected)  
Modes of Operation  
The 33993 has two operating modes, Normal mode and  
Sleep mode. A discussion on Normal mode begins below.  
A discussion on Sleep mode begins on page 18.  
Programmable Switch Register  
Inputs SP0 to SP7 may be programmable for switch-to-  
battery or switch-to-ground. These inputs types are defined  
using the settings command (refer to Table 1). To set an SPn  
input for switch-to-battery, a logic [1] for the appropriate bit must  
be set. To set an SPn input for switch-to-ground, a logic [0] for  
the appropriate bit must be set. The MCU may change or  
update the Programmable Switch Register via software at any  
time in Normal mode. Regardless of the setting, when the SPn  
input switch is closed a logic [1] will be placed in the Serial  
Output Response Register (refer to Table 12, page 17).  
Table 1. Settings Command  
Settings Command  
Not used  
Battery/Ground Select  
23  
0
22  
0
21  
0
20  
0
19  
0
18  
0
17  
0
16  
1
15  
X
14  
X
13  
X
12  
X
11  
X
10  
X
9
8
7
6
5
4
3
2
1
0
X
X
sp7 sp6 sp5 sp4 sp3 sp2 sp1 sp0  
33993/D  
12  
MOTOROLA ANALOG INTEGRATED CIRCUIT DEVICE DATA  
Wake-Up/Interrupt Register  
The Wake-Up/Interrupt Register defines the inputs that are  
allowed to wake the 33993 from Sleep mode or set the INT pin  
low in Normal mode. Programming the wake-up/interrupt bit to  
logic [0] will disable the specific input from generating an  
interrupt and will disable the specific input from waking the IC in  
Sleep mode (refer to Table 2). Programming the wake-up/  
interrupt bit to logic [1] will enable the specific input to generate  
an interrupt with switch change of state and will enable the  
specific input as wake-up. The MCU may change or update the  
Wake-Up/Interrupt Register via software at any time in Normal  
mode.  
Table 2. Wake-Up /Interrupt Command  
Wake-Up/Interrupt Command  
Command Bits  
23 22 21 20 19 18 17 16  
15  
X
14  
X
13  
X
12  
X
11  
X
10  
X
9
8
7
6
5
4
3
2
1
0
0
0
0
0
0
0
0
0
0
0
0
0
1
1
0
1
X
X
sp7 sp6 sp5 sp4 sp3 sp2 sp1 sp0  
X
X
sg13 sg12 sg11 sg10 sg9 sg8 sg7 sg6 sg5 sg4 sg3 sg2 sg1 sg0  
Wetting Current Register  
The 33993 has two levels of switch contact current, 16 mA  
and 2.0 mA (see Figure 8). The metallic command is used to set  
the switch contact current level (refer to Table 3). Programming  
the metallic bit to logic [0] will set the switch wetting current to  
2.0 mA. Programming the metallic bit to logic [1] will set the  
switch contact wetting current to 16 mA. The MCU may change  
or update the Wetting Current Register via software at any time  
in Normal mode.  
Switch Contact Voltage  
Wetting current is designed to provide higher levels of current  
during switch closure. The higher level of current is designed to  
keep switch contacts from building up oxides that form on the  
switch contact surface.  
16 mA Switch Wetting Current  
2.0 mA Switch Sustain Current  
20 ms Wetting Current Timer  
Figure 8. Contact Wetting and Sustain Current  
Table 3. Metallic Command  
Metallic Command  
Command Bits  
23 22 21 20 19 18 17 16 15  
14  
X
13  
X
12  
X
11  
X
10  
X
9
8
7
6
5
4
3
2
1
0
0
0
0
0
0
0
0
0
0
0
1
1
0
0
0
1
X
X
X
X
sp7 sp6 sp5 sp4 sp3 sp2 sp1 sp0  
X
sg13 sg12 sg11 sg10 sg9 sg8 sg7 sg6 sg5 sg4 sg3 sg2 sg1 sg0  
MOTOROLA ANALOG INTEGRATED CIRCUIT DEVICE DATA  
33993/D  
13  
Wetting Current Timer Register  
Each switch input has a designated 20 ms timer. The timer  
starts when the specific switch input crosses the comparator  
threshold (4.0 V). When the 20 ms timer expires, the contact  
current is reduced from 16 mA to 2.0 mA. The wetting current  
timer may be disabled for a specific input. When the timer is  
disabled, 16 mA of current will continue to flow through the  
closed switch contact. With multiple wetting current timers  
disabled, power dissipation for the IC must be considered.  
The MCU may change or update the Wetting Current Timer  
Register via software at any time in Normal mode. This allows  
the MCU to control the amount of time wetting current is applied  
to the switch contact. Programming the wetting current timer bit  
to logic [0] will disable the wetting current timer. Programming  
the wetting current timer bit to logic [1] will enable the wetting  
current timer (refer to Table 4).  
Table 4. Wetting Current Timer Enable Command  
Wetting Current Timer Commands  
Command Bits  
23 22 21 20 19 18 17 16  
15  
X
14  
X
13  
X
12  
X
11  
X
10  
X
9
8
7
6
5
4
3
2
1
0
0
0
0
0
0
0
0
0
0
1
1
0
1
0
1
0
X
X
sp7 sp6 sp5 sp4 sp3 sp2 sp1 sp0  
X
X
sg13 sg12 sg11 sg10 sg9 sg8 sg7 sg6 sg5 sg4 sg3 sg2 sg1 sg0  
Tri-State Register  
The tri-state command is use to set the SPn or SGn input  
node as high impedance (refer to Table 5). By setting the  
Tri-State Register bit to logic [1], the input will be high  
impedance regardless of the metallic command setting. The  
comparator on each input remains active. This command allows  
the use of each input as a comparator with a 4.0 V threshold.  
The MCU may change or update the Tri-State Register via  
software at any time in Normal mode.  
Table 5. Tri-State Command  
Tri-State Commands  
Command Bits  
23 22 21 20 19 18 17 16  
15  
X
14  
X
13  
X
12  
X
11  
X
10  
X
9
8
7
6
5
4
3
2
1
0
0
0
0
0
0
0
0
0
1
1
0
0
0
1
1
0
X
X
sp7 sp6 sp5 sp4 sp3 sp2 sp1 sp0  
X
X
sg13 sg12 sg11 sg10 sg9 sg8 sg7 sg6 sg5 sg4 sg3 sg2 sg1 sg0  
33993/D  
14  
MOTOROLA ANALOG INTEGRATED CIRCUIT DEVICE DATA  
Analog Select Register  
The analog voltage on switch inputs may be read by the  
MCU using the analog command (refer to Table 6). Internal to  
the IC is a 22-to-1 analog multiplexer. The voltage present on  
the selected input pin is buffered and made available on the  
AMUX output pin. The AMUX output pin is clamped to a  
maximum of VDD volts regardless of the higher voltages present  
on the input pin. After an input has been selected as the analog,  
the corresponding bit in the next SO data stream will be  
logic [0]. When selecting a channel to be read as analog, the  
user must also set the desired current (16 mA, 2.0 mA, or high  
impedance). Setting bit 6 and bit 5 to 0,0 selects the input as  
high impedance. Setting bit 6 and bit 5 to 0,1 selects 2.0 mA,  
and 1,0 selects 16 mA. Setting bit 6 and bit 5 to 1,1 in the  
Analog Select Register is not allowed and will place the input as  
an analog input with high impedance.  
Analog currents set by the analog command are pull-up  
currents for all SGn and SPn inputs (refer to Table 6). The  
analog command does not allow pull-down currents on the SPn  
inputs. Setting the current to 16 mA or 2.0 mA may be useful for  
reading sensor inputs. Further information is provided in the  
Applications section of this datasheet beginning on page 20.  
The MCU may change or update the Analog Select Register via  
software at any time in Normal mode.  
Table 6. Analog Command  
Analog Command  
Not used  
Current Select Analog Channel Select  
23  
0
22  
0
21  
0
20  
0
19  
0
18  
1
17  
1
16  
0
15  
X
14  
X
13  
X
12  
X
11  
X
10  
X
9
8
7
6
5
4
0
3
0
2
0
1
0
0
0
X
X
X
16 mA 2.0mA  
Table 7. Analog Channel  
Bits 43210  
00000  
00001  
00010  
00011  
00100  
00101  
00110  
00111  
01000  
01001  
01010  
01011  
01100  
01101  
01110  
01111  
10000  
10001  
10010  
10011  
10100  
10101  
10110  
Analog Channel Select  
No Input Selected  
SG0  
SG1  
SG2  
SG3  
SG4  
SG5  
SG6  
SG7  
SG8  
SG9  
SG10  
SG11  
SG12  
SG13  
SP0  
SP1  
SP2  
SP3  
SP4  
SP5  
SP6  
SP7  
MOTOROLA ANALOG INTEGRATED CIRCUIT DEVICE DATA  
33993/D  
15  
Calibration of Timers  
In cases where an accurate time base is required, the user  
may calibrate the internal timers using the calibration command  
(refer to Table 8). After the 33993 device receives the  
changes with temperature, calibration is required for an  
accurate time base. Calibrating the timers has no affect on the  
quiescent current measurement. The calibration command  
simply makes the time base more accurate. The calibration  
command may be used to update the device on a periodic  
basis.  
calibration command, the device expects 512 µs logic [0]  
calibration pulse on the CS pin. The pulse is used to calibrate  
the internal clock. No other SPI pins should transition during this  
512 µs calibration pulse. Because the oscillator frequency  
Table 8. Calibration Command  
Calibration Command  
Command Bits  
23  
0
22  
0
21  
0
20  
0
19  
1
18  
0
17  
1
16  
1
15  
X
14  
X
13  
X
12  
X
11  
X
10  
X
9
8
7
6
5
4
3
2
1
0
X
X
X
X
X
X
X
X
X
X
Reset  
The reset command resets all registers to Power-ON Reset  
(POR) state. Refer to Table 10, page 17, for POR states or the  
paragraph entitled Power-ON Reset (POR) on page 12 of this  
datasheet.  
Table 9. Reset Command  
Reset Command  
Command Bits  
23  
0
22  
1
21  
1
20  
1
19  
1
18  
1
17  
1
16  
1
15  
X
14  
X
13  
X
12  
X
11  
X
10  
X
9
8
7
6
5
4
3
2
1
0
X
X
X
X
X
X
X
X
X
X
33993/D  
16  
MOTOROLA ANALOG INTEGRATED CIRCUIT DEVICE DATA  
SPI Command Summary  
Table 10 below provides a comprehensive list of SPI  
commands recognized by the 33993 and the reset state of each  
register. Table 11 and Table 12 contain the Serial Output (SO)  
data for input voltages greater or less than the threshold level.  
Open switches are always indicated with a logic [0], closed  
switches are indicated with logic [1].  
Table 10. SPI Command Summary  
MSB  
Command Bits  
Setting Bits  
LSBI  
23  
22  
0
21  
0
20  
19  
18  
17  
0
16  
0
15  
X
14  
X
13  
X
12  
X
11  
X
10  
X
9
8
7
6
5
4
3
2
1
0
Switch Status  
Command  
0
0
0
0
X
X
X
X
X
X
X
X
X
X
Settings Command  
Bat=1, Gnd=0  
(Default state = 1)  
0
0
0
0
0
0
0
0
0
0
0
0
0
1
1
0
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
SP7 SP6 SP5 SP4 SP3 SP2 SP1 SP0  
SP7 SP6 SP5 SP4 SP3 SP2 SP1 SP0  
Wake-Up/Interrupt Bit  
Wake-Up=1  
Nonwake-Up=0  
(Default state = 1)  
0
0
0
0
0
0
0
0
0
0
0
1
1
0
1
0
X
X
X
X
SG13 SG12 SG11 SG10 SG9 SG8 SG7 SG6 SG5 SG4 SG3 SG2 SG1 SG0  
SP7 SP6 SP5 SP4 SP3 SP2 SP1 SP0  
Metallic Command  
Metallic = 1  
X
X
X
X
X
X
Non-metallic = 0  
(Default state = 1)  
0
0
0
0
0
1
0
1
X
X
SG13 SG12 SG11 SG10 SG9 SG8 SG7 SG6 SG5 SG4 SG3 SG2 SG1 SG0  
16mA 2.0mA  
Analog Command  
0
0
0
0
0
0
0
0
0
0
1
1
1
1
0
1
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
0
0
0
0
0
0
0
Wetting Current Timer  
Enable Command  
Timer ON = 1  
SP7 SP6 SP5 SP4 SP3 SP2 SP1 SP0  
0
0
0
0
1
0
0
0
X
X
SG13 SG12 SG11 SG10 SG9 SG8 SG7 SG6 SG5 SG4 SG3 SG2 SG1 SG0  
Timer OFF = 0  
(Default state = 1)  
Tri-State Command  
Input Tri-State=1  
Input Active = 0  
0
0
0
0
0
0
0
0
1
1
0
0
0
1
1
0
X
X
X
X
X
X
X
X
X
X
SP7 SP6 SP5 SP4 SP3 SP2 SP1 SP0  
SG13 SG12 SG11 SG10 SG9 SG8 SG7 SG6 SG5 SG4 SG3 SG2 SG1 SG0  
(Default state = 1)  
Calibration Command  
(Default state -  
uncalibrated)  
0
0
0
0
0
0
0
0
1
1
0
1
1
0
1
0
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Sleep Command  
int  
int  
int  
scan scan scan  
(See Sleep Mode on  
timer timer timer timer timer timer  
page 18)  
Reset Command  
Test Mode  
0
1
1
1
1
1
1
1
1
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
them  
flg  
int  
flg  
SO Response Will  
Always Send  
SP7 SP6 SP5 SP4 SP3 SP2 SP1 SP0 SG13 SG12 SG11 SG10 SG9 SG8 SG7 SG6 SG5 SG4 SG3 SG2 SG1 SG0  
Table 11. Serial Output (SO) Bit Data  
Input  
Voltage on  
Input Pin  
Type of Input  
SO SPI Bit  
Programmed  
Switch to Ground  
Switch to Ground  
Switch to Battery  
Switch to Battery  
N/A  
SPn < 4.0 V  
SPn > 4.0 V  
SPn < 4.0 V  
SPn > 4.0 V  
SGn < 4.0 V  
SGn > 4.0 V  
1
0
0
1
1
0
SP  
SG  
N/A  
Table 12. Serial Output (SO) Response Register  
SO Response Will  
Always Send  
them  
flg  
int  
flg  
SP7 SP6 SP5 SP4 SP3 SP2 SP1 SP0 SG13 SG12 SG11 SG10 SG9 SG8 SG7 SG6 SG5 SG4 SG3 SG2 SG1 SG0  
MOTOROLA ANALOG INTEGRATED CIRCUIT DEVICE DATA  
33993/D  
17  
Example of Normal Mode Operation  
Sleep Mode  
Sleep mode is used to reduce system quiescent currents.  
Sleep mode may be entered only by sending the sleep  
command. All register settings programmed in Normal mode  
will be maintained in Sleep mode.  
The operation of the device in Normal Mode is defined by the  
states of the programmable internal control registers. A typical  
application may have the following settings:  
• Programmable Switch – Set to Switch-to-Ground  
• All Inputs Set as Wake-Up  
The 33993 will exit Sleep mode and enter Normal mode  
when any of the following events occur:  
• Wetting Current On (16 mA)  
• Wetting Current Timer On (20 ms)  
• Input Switch Change of State (when enabled)  
• Interrupt Timer Expire  
• Falling Edge of WAKE  
• Falling Edge of INT (with VDD = 5.0 V and WAKE at  
Logic [1])  
• Falling Edge of CS (with VDD = 5.0 V)  
• All inputs Tri-State-Disabled (comparator is active)  
• Analog select 00000 (no input channel selected)  
With the device programmed as above, an interrupt will be  
generated with each switch contact change of state (open-to-  
close or close-to-open) and 16 mA of contact wetting current  
will be source for 20 ms. The INT pin will remain low until switch  
status is acknowledged by the microprocessor. It is critical to  
understand INT will not be cleared on the rising edge of CS if a  
switch closure occurs while CS is low. The maximum duration a  
switch state change can exist without acknowledgement  
depends on the software response time to the interrupt.  
Figure 4, page 8, shows the interaction between changing input  
states and the INT and CS pins.  
• Power-ON Reset (POR)  
The VDD supply may be removed from the device during  
Sleep mode. However removing VDD from the device in Sleep  
mode will disable a wake-up from falling edge of INT and CS.  
Note In cases where CS is used to wake the device, the first  
SO data message is not valid.  
If desired the user may disable interrupts (wake up/interrupt  
command) from the 33993 device and read the switch states on  
a periodic basis. Switch activation and deactivation faster than  
the MCU read rate will not be acknowledged.  
The sleep command contains settings for two programmable  
timers for Sleep mode, the interrupt timer and the scan timer, as  
shown in Table 13.  
The interrupt timer is used as a periodic wake-up timer.  
When the timer expires, an interrupt is generated and the  
device enters Normal mode. Table 14 shows the  
programmable settings of the Interrupt timer.  
The 33993 device will exit the Normal mode and enter the  
Sleep mode only with a valid sleep command.  
Table 13. Sleep Command  
Sleep Command  
Command Bits  
23  
0
22  
0
21  
0
20  
0
19  
1
18  
1
17  
0
16  
0
15  
X
14  
X
13  
X
12  
X
11  
X
10  
X
9
8
7
6
5
4
3
2
1
0
X
X
X
X
Table 14. Interrupt Timer  
Bits 543  
Interrupt Period  
32 ms  
000  
001  
010  
011  
100  
101  
110  
111  
64 ms  
128 ms  
256 ms  
512 ms  
1.024 s  
2.048 s  
4.096 s  
33993/D  
18  
MOTOROLA ANALOG INTEGRATED CIRCUIT DEVICE DATA  
The scan timer sets the polling period between input switch  
reads in Sleep mode. The period is set in the sleep command  
and may be set to 000 (no period) to 111 (64 ms). In Sleep  
mode when the scan timer expires, inputs will behave as  
programmed prior to sleep command. The 33993 will wake up  
for approximately 125 µs and read the switch inputs. At the end  
of the 125 µs, the input switch states are compared with the  
switch state prior to sleep command. When switch state  
changes are detected, an interrupt (when enabled; refer to  
wake-up/interrupt command description on page 13) is  
generated and the device enters Normal mode. Without switch  
state changes, the 33993 will reset the scan timer, inputs  
become tri-state, and the Sleep mode continues until the scan  
timer expires again.  
quiescent current is calculated by integrating the normal  
running current over scan period plus approximately 60 µA.  
I=V/R or 0.270 V/100 =2.7 mA  
Table 15 shows the programmable settings of the Scan  
timer.  
Inputs active for  
A  
I=V/R or  
125 µs out of 32 ms  
6.0 mV/100 =60 µA  
Table 15. Scan Timer  
Bits 210  
000  
Scan Period  
No Scan  
1.0 ms  
Figure 9. Sleep Current Waveform  
Temperature Monitor  
With multiple switch inputs closed and the device  
programmed with the wetting current timers disabled,  
considerable power will be dissipated by the IC. For this reason  
temperature monitoring has been implemented. The  
temperature monitor is active in the Normal mode only. When  
the IC temperature is above the thermal limit, the temperature  
monitor will do all of the following:  
001  
010  
2.0 ms  
011  
4.0 ms  
100  
8.0 ms  
101  
16 ms  
110  
32 ms  
111  
64 ms  
• Generate an interrupt.  
• Force all 16 mA pull-up and pull-down current sources to  
revert to 2.0 mA current sources.  
Note The interrupt and scan timers are disabled in the  
Normal mode.  
• Maintain the 2.0 mA current source and all other  
functionality.  
Figure 3, page 8, is a graphical description of how the 33993  
device exits Sleep mode and enters Normal mode. Notice that  
the device will exit Sleep mode when the interrupt timer expires  
or when a switch change of state occurs. The falling edge of INT  
triggers the MCU to wake from Sleep state. Figure 9 illustrates  
the current consumed during Sleep mode. During the 125 µs,  
the device is fully active and switch states are read. The  
• Set the thermal flag bit in the SPI output register.  
The thermal flag bit in the SPI word will be cleared on rising  
edge of CS provided the die temperature has cooled below the  
thermal limit. When die temperature has cooled below thermal  
limit, the device will resume previously programmed settings.  
MOTOROLA ANALOG INTEGRATED CIRCUIT DEVICE DATA  
33993/D  
19  
APPLICATIONS  
Introduction  
Metallic/Elastomeric Switch  
The 33993’s primary function is the detection of open or  
closed switch contacts. However, there are many features that  
allow the device to be used in a variety of applications. The  
following is a list of applications to consider for the IC:  
Metallic switch contacts often develop higher contact  
resistance over time owing to contact corrosion. The corrosion  
is induced by humidity, salt, and other elements that exist in the  
environment. For this reason the 33993 provides two settings  
for contacts. When programmed for metallic switches, the  
device provides higher wetting current to keep switch contacts  
free of oxides. The higher current occurs for the first 20 ms of  
switch closure. Where longer duration of wetting current is  
desired, the user may send the wetting current timer command  
and disable the timer. Wetting current will be continuous to the  
closed switch. After the time period set by the MCU, the wetting  
current timer command may be sent again to enable the timer.  
The user must consider power dissipation on the device when  
disabling the timer. (Refer to the paragraph entitled  
• Sensor Power Supply  
• Switch Monitor for Metallic or Elastomeric Switches  
• Analog Sensor Inputs (Ratiometric)  
• Power MOSFET/LED Driver and Monitor  
• Multiple 33993 Devices in a Module System  
The following paragraphs describe the applications in detail.  
Sensor Power Supply  
Temperature Monitor, page 19.)  
Each input may be used to supply current to sensors external  
to a module. Many sensors such as Hall effect, pressure  
sensors, and temperature sensors require a supply voltage to  
power the sensor and provide an open collector or analog  
output. Figure 10 shows how the 33993 may be used to supply  
power and interface to these types of sensors. In an application  
where the input makes continuous transitions, consider using  
the wake-up/interrupt command to disable the interrupt for the  
particular input.  
To increase the amount of wetting current for a switch  
contact, the user has two options. Higher wetting current to a  
switch may be achieved by paralleling SGn or SPn inputs. This  
will increase wetting current by 16 mA for each input added to  
the switch contact. The second option is to simply add an  
external resistor pull-up to the VPWR supply for switch-to-ground  
inputs or a resistor to ground for a switch-to-battery input.  
Adding an external resistor has no effect on the operation of the  
device.  
33993  
SP0  
VPWR  
SP1  
Elastomeric switch contacts are made of carbon and have a  
high contact resistance. Resistance of 1.0 kis common. In  
applications with elastomeric switches, the pull-up and pull-  
down currents must be reduced to prevent excessive power  
dissipation at the contact. Programming for a lower current  
settings is provided in the Device Operation Section beginning  
on page 12 under Table 3, Metallic Command.  
VBAT  
V
DD  
MCU  
VDD  
VBAT  
SP7  
WAKE  
SI  
SCLK  
CS  
MOSI  
SCLK  
CS  
SG0  
SG1  
Analog Sensor Inputs (Ratiometric)  
V
V
PWR PWR  
The 33993 features a 22-to-1 analog multiplexer. Setting the  
binary code for a specific input in the analog command allows  
the microcontroller to perform analog to digital conversion on  
any of the 22 inputs. On rising edge of CS the multiplexer  
connects a requested input to the AMUX pin. The AMUX pin is  
clamped to max of VDD volts regardless of the higher voltages  
present on the input pin. After an input has been selected as the  
analog, the corresponding bit in the next SO data stream will be  
logic [0].  
SO  
INT  
MISO  
INT  
16  
mA  
2.0  
mA  
16 mA  
SG12  
SG13  
V
V
PWR PWR  
Hall-Effect  
Sensor  
Reg  
16  
2.0  
mA  
mA  
X
2.5 kΩ  
IOC[7:0]  
The input pin, when selected as analog, may be configured  
as analog with high impedance, analog with 2.0 mA pull-up, or  
analog with 16 mA pull-up. Figure 11, page 21, shows how the  
33993 may be used to provide a ratiometric reading of variable  
resistive input.  
Input Capture  
Timer Port  
2.5 kΩ  
Figure 10. Sensor Power Supply  
33993/D  
20  
MOTOROLA ANALOG INTEGRATED CIRCUIT DEVICE DATA  
conversion may be obtained. Using the equation yields the  
following:  
33993  
VBAT  
VBAT  
SP0  
SP1  
VPWR  
VDD  
I1 x R1  
I2 x R2  
VDD  
ADC =  
x 225  
MCU  
2.0 mA x 2.0 kΩ  
2.0 mA x 2.39 kΩ  
ADC =  
x 225  
SP7  
WAKE  
SI  
SCLK  
CS  
MOSI  
SCLK  
CS  
ADC = 213 counts  
SG0  
SG1  
V
V
PWR PWR  
The ADC value of 213 counts is the value with 0% error  
(neglecting the resistor tolerance and AMUX input offset  
voltage). Now we can calculate the count value induced by the  
mismatch in current sources. From a sample device the  
maximum current source was measured at 2.05 mA and  
minimum current source was measured at 1.99 mA. This yields  
3% error in A/D conversion. The A/D measurement will be as  
follows:  
MISO  
INT  
SO  
INT  
AMUX  
16  
mA  
2.0  
mA  
I1  
2.0 mA  
SG12  
AN0  
V
V
R
PWR PWR  
1
Analog  
Ports  
16  
2.0  
mA  
Analog Sensor  
mA  
or Analog Switch  
SG13  
1.99 mA x 2.0 kΩ  
2.05 mA x 2.39 kΩ  
I
2.02mA  
4.54 V to 5.02 V  
ADC =  
x 225  
V
REF(H)  
2.39 kΩ  
R
2
0.1%  
ADC = 207 counts  
V
REF(L)  
This A/D conversion is 3% low in value. The error correction  
factor of 1.03 may be used to correct the value:  
Figure 11. Analog Ratiometric Conversion  
To read a potentiometer sensor, the wiper should be  
ADC = 207 counts x 1.03  
ADC = 213 counts  
grounded and brought back to the module ground, as illustrated  
-
in Figure 11. With the wiper changing the impedance of the  
sensor, the analog voltage on the input will represent the  
position of the sensor.  
An error correction factor may then be stored in E2 memory  
and used in the A/D calculation for the specific input. Each input  
used as analog measurement will have a dedicated calibrated  
error correction factor.  
Using the Analog feature to provide 2.0 mA of pull-up current  
to an analog sensor may induce error due to the accuracy of the  
current source. For this reason, a ratiometric conversion must  
be considered. Using two current sources (one for the sensor  
and one to set the reference voltage to the A/D converter) will  
yield a maximum error (owing to the 33993) of 4%.  
Power MOSFET/LED Driver and Monitor  
Because of the flexible programming of the 33993 device, it  
may be used to drive small loads like LEDs or MOSFET gates.  
It was specifically designed to power up in the Normal mode  
with the inputs tri-state. This was done to ensure the LEDs or  
MOSFETs connected to the 33993 power up in the off-state.  
The Switch Programmable (SP0–SP7) inputs have a source-  
and-sink capability, providing effective MOSFET gate control.  
To complete the circuit, a pull-down resistor should be used to  
keep the gate from floating during the Sleep modes. Figure 12,  
page 22, shows an application where the SG0 input is used to  
monitor the drain-to-source voltage of the external MOSFET.  
The 1.5 kresistor is used to set the drain-to-source trip  
voltage. With the 2.0 mA current source enabled, an interrupt  
will be generated when the drain-to-source voltage is  
approximately 1.0 V.  
Higher accuracy may be achieved through module level  
calibration. In this example, we use the resistor values from  
Figure 11 and assume the current sources are 4% from each  
other. The user may use the module end-of-line tester to  
calculate the error in the A/D conversion. By placing a 2.0 k,  
0.1% resistor in the end-of-line test equipment and assuming a  
perfect 2.0 mA current source from the 33993, a calculated A/D  
MOTOROLA ANALOG INTEGRATED CIRCUIT DEVICE DATA  
33993/D  
21  
down to ground through an external resistor. The open load is  
indicated by a logic [1] in the SO data bit.  
VBAT  
The analog command may be used to monitor the drain  
voltage in the MOSFET ON state. By sourcing 2.0 mA of current  
to the 1.5 kresistor, the analog voltage on the SGn pin will be  
approximately:  
V
V
PWR PWR  
SG0  
16  
mA  
2.0  
mA  
1.5 kΩ  
100 kΩ  
SG0  
SP0  
AMUX  
VSGn = ISGn x 1.5 k+ VDS  
+
-
To SPI  
4.0 V Ref  
As the voltage on the drain of the MOSFET increases, so  
does the voltage on the SGn pin. With the SGn pin selected as  
analog, the MCU may perform the A/D conversion.  
Comparator  
V
V
PWR  
PWR  
SG0  
16  
2.0  
Using this method for controlling unclamped inductive loads  
is not recommended. Inductive flyback voltages greater than  
mA  
mA  
VPWR may damage the IC.  
+
-
To SPI  
4.0 V  
Ref  
The SP0–SP7 pins of this device may also be used to send  
16  
Comparator  
mA  
signals from one module to another. Operation is similar to the  
gate control of a MOSFET.  
2.0 mA  
V
V
PWR PWR  
SG13  
For LED applications a resistor in series with the LED is  
recommended but not required. The switch-to-ground inputs  
are recommended for LED application. To drive the LED use  
the following commands:  
16  
mA  
2.0  
mA  
SG13  
+
-
To SPI  
4.0 V Ref  
wetting current timer enable command –Disable SGn  
wetting current timer.  
metallic command –Set SGn to 16 mA.  
Comparator  
From this point forward the LED may be turned on and off using  
Figure 12. MOSFET or LED Driver Output  
the tri-state command:  
The sequence of commands (from Normal mode with inputs  
tri-state) required to set up the device to drive a MOSFET are  
as follows:  
tri-state command –Disable tri-state for SGn (LED ON).  
tri-state command –Enable tri-state for SGn (LED OFF).  
These parameters are easily programmed via SPI commands  
in Normal mode.  
wetting current timer enable command –Disable SPn  
wetting current timer (refer to Table 4, page 14).  
metallic command –Set SPn to 16 mA or 2.0 mA gate  
drive current (refer to Table 3, page 13).  
settings command –Set SPn as switch-to-battery (refer to  
Table 1, page 12).  
Multiple 33993 Devices in a Module System  
Connecting power to the 33993 and the MCU for Sleep mode  
operation may be done in several ways. Table 16 shows  
several system configurations for power between the MCU and  
the 33993 and their specific requirements for functionality.  
tri-state command –Disable tri-state for SPn (refer to  
Table 5, page 14).  
Table 16. Sleep Mode Power Supply  
After the tri-state command has been sent (tri-state disable),  
the MOSFET gate will be pulled to ground. From this point  
forward the MOSFET may be turned on and off by sending the  
settings command:  
MCU  
VDD  
33993  
VDD  
Comments  
5.0 V  
5.0 V  
All wake-up conditions apply. (Refer to Sleep  
Mode, page 18.)  
settings command –SPn as switch-to-ground (MOSFET  
ON).  
5.0 V  
0 V  
0 V  
SPI wake-up is not possible.  
settings command –SPn as switch-to-battery (MOSFET  
5.0 V  
Sleep mode not possible. Current from CS pull  
up will flow through MCU to VDD that has been  
OFF).  
Monitoring of the MOSFET drain in the OFF state provides  
open load detection. This is done by using an SGn input  
comparator. With the SGn input in tri-state, the load will pull up  
the SGn input to battery. With open load the SGn pin is pulled  
switched off. Negative edge of CS will put 33993  
in Normal mode.  
0 V  
0 V  
SPI wake-up is not possible.  
33993/D  
22  
MOTOROLA ANALOG INTEGRATED CIRCUIT DEVICE DATA  
Multiple 33993 devices may be used in a module system.  
SPI control may be done in parallel or serial. However when  
parallel mode is used, each device is addressed independently  
(refer to MCU Interface Description on page 11). Therefore  
when sending the sleep command, one device will enter sleep  
before the other. For multiple devices in a system, it is  
The 33993 IC has an internal 5.0 V supply from VPWR pin. A  
POR circuit monitors the internal 5.0 V supply. In the event of  
transients on the VPWR pin, an internal reset may occur. Upon  
reset the 33993 will enter Normal mode with the internal  
registers as defined in Table 10, page 17. Therefore it is  
recommended that the MCU periodically update all registers  
internal to the IC.  
recommended that the devices are controlled in serial (S0 from  
first device is connected to SI of second device). With two  
devices, 48 clock pulses are required to shift data in. When the  
WAKE feature is used to enable the power supply, both WAKE  
pins should be connected to the enable pin on the power  
supply. The INT pins may be connected to one interrupt pin on  
the MCU or may have their own dedicated interrupt to the MCU.  
Using the WAKE Feature  
The 33993 provides a WAKE output and wake-up input  
designed to control an enable pin on system power supply.  
While in the Normal mode, the WAKE output is low, enabling the  
power supply. In the Sleep mode, the WAKE pin is high,  
disabling the power supply. The WAKE pin has a passive pull-  
up to the internal 5.0 V supply but may be pulled up through a  
resistor to VPWR supply (see Figure 14, page 24)  
The transition from Normal to Sleep mode is done by  
sending the sleep command. With the devices connected in  
serial and the sleep command sent, both will enter Sleep mode  
on the rising edge of CS. When Sleep mode is entered, the  
WAKE pin will be logic [1]. If either device wakes up, the WAKE  
pin will transition low, waking the other device.  
When the WAKE output is not used the pin should be pulled  
up to the VDD supply through a resistor as shown in Figure 13,  
page 24.  
A condition exists where the MCU is sending the sleep  
command (CS logic [0]) and a switch input changes state. With  
this event the device that detects this input will not transition to  
Sleep mode, while the second device will enter Sleep mode. In  
this case two switch status commands must be sent to receive  
accurate switch status data. The first switch status command  
will wake the device in Sleep mode. Switch status data may not  
be valid from the first switch status command because of the  
time required for the input voltage to rise above the 4.0 V input  
comparator threshold. This time is dependant on the  
impedance of SGn or SPn node. The second switch status  
command will provide accurate switch status information. It is  
recommended that software wait 10 ms to 20 ms between the  
two switch status commands, allowing time for switch input  
voltages to stabilize. With all switch states acknowledged by the  
MCU, the sleep sequence may be initiated. All parameters for  
Sleep mode should be updated prior to sending the sleep  
command.  
During the Sleep mode, a switch closure will set the WAKE  
pin low, causing the 33993 to enter the Normal mode. The  
power supply will then be activated, supplying power to the VDD  
pin and the microprocessor and the 33993. The microprocessor  
can determine the source of the wake-up by reading the  
interrupt flag.  
Cost and Flexibility  
Systems requiring a significant number of switch interfaces  
have many discrete components. Discrete components on  
standard PWB consume board space and must be checked for  
solder joint integrity. An integrated approach reduces solder  
joints, consumes less board space, and offers wider operating  
voltage, analog interface capability, and greater interfacing  
flexibility.  
MOTOROLA ANALOG INTEGRATED CIRCUIT DEVICE DATA  
33993/D  
23  
VPWR  
VDD  
VDD  
VBAT  
VBAT  
Power  
Supply  
33993  
VPWR  
VPWR  
SP0  
SP1  
VDD  
VDD  
VBAT  
MC68HCXX  
SP7  
Microprocessor  
WAKE  
CS  
CS  
SG0  
SG1  
INT  
SI  
INT  
MOSI  
MISO  
SO  
SCLK  
SCLK  
AN0  
AMUX  
SG12  
SG13  
Figure 13. Power Supply Active in Sleep Mode  
VPWR VDD  
VDD  
VBAT  
VBAT  
Power  
Supply  
33993  
VPWR  
Enable  
VPWR  
SP0  
SP1  
VDD  
WAKE  
VDD  
VBAT  
MC68HCXX  
SP7  
Microprocessor  
CS  
CS  
SG0  
SG1  
INT  
SI  
INT  
MOSI  
MISO  
SO  
SCLK  
SCLK  
AN0  
AMUX  
SG12  
SG13  
Figure 14. Power Supply Shutdown in Sleep Mode  
33993/D  
24  
MOTOROLA ANALOG INTEGRATED CIRCUIT DEVICE DATA  
PACKAGE DIMENSIONS  
DWB SUFFIX  
32-LEAD SOIC WIDE BODY  
PLASTIC PACKAGE  
CASE 1324-02  
ISSUE A  
10.3  
NOTES:  
1. ALL DIMENSIONS ARE IN MILLIMETERS.  
2. DIMENSIONING AND TOLERANCING PER ASME  
Y14.5M, 1994.  
3. DATUMS B AND C TO BE DETERMINED AT THE PLANE  
WHERE THE BOTTOM OF THE LEADS EXIT THE  
PLASTIC BODY.  
7.6  
7.4  
C
B
2.65  
2.35  
5
9
4. THIS DIMENSION DOES NOT INCLUDE MOLD FLASH,  
PROTRUSION OR GATE BURRS. MOLD FLASH,  
PROTRUSION OR GATE BURRS SHALL NOT EXCEED  
0.15 MM PER SIDE. THIS DIMENSION IS DETERMINED  
AT THE PLANE WHERE THE BOTTOM OF THE LEADS  
EXIT THE PLASTIC BODY.  
30X  
0.65  
1
32  
5. THIS DIMENSION DOES NOT INCLUDE INTERLEAD  
FLASH OR PROTRUSIONS. INTERLEAD FLASH AND  
PROTRUSIONS SHALL NOT EXCEED 0.25 MM PER  
SIDE. THIS DIMENSION IS DETERMINED AT THE  
PLANEWHERETHEBOTTOMOFTHELEADSEXITTHE  
PLASTIC BODY.  
6. THIS DIMENSION DOES NOT INCLUDE DAMBAR  
PROTRUSION. ALLOWABLE DAMBAR PROTRUSION  
SHALL NOT CAUSE THE LEAD WIDTH TO EXCEED 0.4  
MM PER SIDE. DAMBAR CANNOT BE LOCATED ON  
THE LOWER RADIUS OR THE FOOT. MINIMUM SPACE  
BETWEEN PROTRUSION AND ADJACENT LEAD  
SHALL NOT LESS THAN 0.07 MM.  
7. EXACT SHAPE OF EACH CORNER IS OPTIONAL.  
8. THESE DIMENSIONS APPLY TO THE FLAT SECTION  
OF THE LEAD BETWEEN 0.10 MM AND 0.3 MM FROM  
THE LEAD TIP.  
9. THE PACKAGE TOP MAY BE SMALLER THAN THE  
PACKAGE BOTTOM. THIS DIMENSION IS  
PIN 1 ID  
4
11.1  
10.9  
C
L
9
B
B
16  
17  
SEATING  
A
PLANE  
5.15  
2X 16 TIPS  
0.3  
32X  
0.10  
A
DETERMINED AT THE OUTERMOST EXTREMES OF  
THE PLASTIC BODY EXCLUSIVE OF MOLD FLASH, TIE  
BAR BURRS, GATE BURRS AND INTER-LEAD FLASH,  
BUT INCLUDING ANY MISMATCH BETWEEN THE TOP  
AND BOTTOM OF THE PLASTIC BODY.  
A
B C  
A
A
(0.29)  
BASE METAL  
0.25  
0.19  
(0.203)  
R0.08 MIN  
0.25  
°
0
0.38  
0.22  
0.29  
0.13  
GAUGE PLANE  
MIN  
PLATING  
6
M
M
0.13  
C
A
B
8
0.9  
0.5  
SECTION A-A  
°
°
8
0
ROTATED 90 CLOCKWISE  
°
SECTION B-B  
MOTOROLA ANALOG INTEGRATED CIRCUIT DEVICE DATA  
33993/D  
25  
NOTES  
33993/D  
26  
MOTOROLA ANALOG INTEGRATED CIRCUIT DEVICE DATA  
NOTES  
MOTOROLA ANALOG INTEGRATED CIRCUIT DEVICE DATA  
33993/D  
27  
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MC33993/D  

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MOTOROLA

MC33996

16 Output Switch with SPI Control
FREESCALE

MC33996EK

16 Output Switch with SPI Control
FREESCALE

MC33996EKR2

16-Output Switch with SPI Control
FREESCALE

MC33997

Switching Power Supply with Linear Regulators
MOTOROLA

MC33997DW

Switching Power Supply with Linear Regulators
MOTOROLA

MC33997DW/R2

Switching Power Supply with Linear Regulators
MOTOROLA

MC33997DWR2

Switching Power Supply with Linear Regulators
FREESCALE

MC33998

Switching Power Supply with Linear Regulators
FREESCALE

MC33998D

Switching Power Supply with Linear Regulators
FREESCALE