MOTOROLA
SEMICONDUCTOR
TECHNICAL DATA
MC33285
HIGH SIDE
TMOS DRIVER
SILICON MONOLITHIC
INTEGRATED CIRCUIT
Product Preview
Automotive Dual High
Side TMOS Driver
The MC33285 is a dual high side TMOS driver designed for use in
the harsh automotive switching applications.
The purpose of the MC33285 is to drive two power n-channel FETs in
a high side application with an inductive load. The application in an
automotive environment requires the capability of withstanding high
voltages and load dump transients. The MC33285 is able to withstand
reverse battery conditions at selected pins.
It protects the n-channel power FET on OUT1 under over current
condition. This device has one input to control both stages on or off.
•
Temperature Range from -40° to +125°
C
C
•
PWM Capability
•
Power TMOS # 1 Over-Current and Short-Circuit Protection
•
Voltage Range 7V to 40V
•
Extended Temperature Range from -40° to 125°
C
C
•
Load Dump Protected
•
Over Voltage Detection and Activation of OUT2 during Overvoltage
•
Single Input Control for both Output Stages
•
Capacitor Value of 100nF Connected to Pin CP
•
Analog Input Control Measurement Detection
•
OUT1 LOAD leakage measurement detection
PIN CONNECTIONS
SRC
1
OUT1
2
DRN
3
OUT2
4
8
7
6
5
IN
GND
V
CC
CP
ORDERING INFORMATION
Device
MC33285D
Temperature
Range
C
C
-40° to +125°
Package
SO8
Block Diagram And Typical Application
V
IGN
Kl.30
CP
VCC
C
CP
+
V
REF
-
Load Dump
Detection
IN
THRIN2
S
R
t
LDdet
Oscillator
and
Divider
Charge
pump
Band-
gap
Rthr
DRN
I
ON2
I
ON1
t
OUT2ect
R Q
+
-
+
OUT2 Activation
Time
S
I
OUTN2
OUT2
V
OUT2
-V
DRN
> V
TH2
OUT1
V
OUT1
-V
SRC
> V
TH1
THRIN1
GND
-
OC Detection
I
OUTN1
R Q
S
t
OCdet
start t
OCdet
OCPC
M
+
-
SRC
This document contains information on a new product under development. Motorola reserves the
©
Motorola,Inc 1999
right to change or discontinue this product without notice.
Rev 2.4
MC33285
MAXIMUM RATING
Rating
Maximum voltage at pins OUT1 OUT2
Maximum voltage at pin CP
Input voltage V
i
at DRN
Input voltage V
i
at SRC
Input voltage at pin V
CC
Input Voltage at pin IN. Condition : -2V<V
VCC
<40V
Operational voltage V
VCC
at pin V
CC
THERMAL RATINGS
Rating
Storage Temperature
Operating ambient temperature
Symbol
T
stg
T
a
Value
-40 to +150
-40 to +125
Unit
°
C
°
C
Symbol
V
O U T
V
CP
V
DRN
V
SRC
V
CC
V
IN
V
VCC
Value
V
VCC
+ 20
50
-2 ; 40
-5 ; 40
-2 to 40
-2 to V
VCC
7 to V
i
Unit
V
V
V
V
V
V
V
ELECTRICAL CHARACTERISTICS.
(T
A
from -40
°
C to +125°C, Vcc from 7V to 20V, unless otherwise noted)
Characteristic
Symbol
Min
Typ
Max
Unit
OVERVOLTAGE AND OVERCURRENT
Load Dump Detection Time
Load Dump Activation Time
Error Voltage Threshold
Overcurrent Detection Time
tLD
det
tOUT2act
VDRN - VSRC
tOCdet
250
300
1.12
520
800
400
460
550
620
1.44
1080
µs
ms
V
µs
SRC PIN 1
Leakage Current
Leakage Current Detection Time
ILC
det
tLC
det
15
130
30
200
50
270
mA
µs
DRN PIN 3
Operating Current (7V<V
DRN
<20V)
Leakage current (0V<V
DRN
<20V, V
VCC
<4V)
I
DRN
I
leak_DRN
-5
1.5
5
mA
µA
OUT1 PIN2, OUT 2 PIN 4
Output On Voltage. Charge Pump ON
Turn off current, Vout >0.5V
Turn On Time, OUT1: 8nF,10µΑ
;
OUT2:
16nF,10µΑ
- 7V < Vcc < 10V, Vout > Vcc+7
- 10V < Vcc < 20V, Vout > Vcc+11
Von
Ioutoff
ton
1.5
1.5
66
110
Vcc+15
154
V
µA
ms
VCC PIN 6
Supply Voltage Range
Quiescent Supply Current at Vcc = 20V
Vcc
Icc
7
40
10
V
mA
IN PIN 8
Input Low Voltage OUT1
Input High Voltage OUT1
Input Hysteresis OUT1, OUT2
Input Pull Down Current, 0.7V<Vin<6V
Open Input Voltage
Input Low Voltage OUT2
Input High Voltage OUT2
Vil
Vih
Vhys
Iin
Viop
Vil2
Vih2
3.9
1.7
0.4
7.5
15
16.5
0.7
3
0.7
V
V
V
µA
V
V
V
MC33285
MOTOROLA
2
MC33285
Turn On Characteristics
The power FETs are turned on by charging their gate capacities with a current flowing out of pin OUT1 and OUT2.
During PWM, the values of table below are guaranteed. They are measured with 8nF on OUT1 and 16nF on OUT2.
- test condition : V
IN
: ramp 0V to 2.5V or 2.5V to 5V.
Figure 1.
Turn-on Behaviour
5V
IN
2.5V
IN
THRIN2
THRIN1
V
CCP
V
OUT1
V
VCC
+7V
V
OUT2
20ms
V
OUT2
2.5V
IN
0V
VOUT1
max
IN
5V
2.5V
VOUT2
max
V
OUT1
0V
0
ton1
ton2
ton3
V
OUT2
0V
0
ton1
ton2
ton3
Table 1 Turn on behaviour
Voltage V
VCC
7V < V
VCC
< 10V
10V < V
VCC
< 20V
20V < V
VCC
< 40V
Minimum V
OUT1,OUT2
after t
on1
= 100µsec
V
VCC
- 0.7V
V
VCC
- 0.7V
V
VCC
- 0.7V
Minimum V
OUT1,OUT2
after t
on2
= 1.0msec
V
VCC
+ 5.95V
V
VCC
+ 9.35V
Minimum V
OUT1,OUT2
after t
on3
= 1.5msec
V
VCC
+ 7V
V
VCC
+ 11V
The output voltages at OUT1 and OUT2 are limited by controlling the current sources I
on1
, I
on2
to avoid currrent flowing
through the external or the internal zener diode .
If Vcc + Vth (threshold voltage) is reached , the current sources are turned off.
- threshold V
TH1
for OUT1 output voltage control : 7V < V
TH1
< Vz
- threshold VTH2 for OUT2 output voltage control : 7V < V
TH2
< 15V
Turn off characteristics
The power FETs on OUT1 and OUT2 are turned off by discharging the gate capacity with the constant discharge current
I
OUToff
.
- discharge current I
OUTxoff
: IOUTxoff = 110µA
condition : V
OUT
x > 0.5V ( V
IN
< V
THRxIN
)
Test conditions for switching off the power FETs :
- 1. IN open
- 2. Stages disabled via pin IN
- 3. Stage OUT1 disabled by an over current error
MC33285
MOTOROLA
3
MC33285
FUNCTIONNAL DESCRIPTION
Introduction
The MC33285 contains only one charge pump for two
outputs.The outputs OUT1 and OUT2 are switched on and off
by the input IN .There are three ways to control the outputs:
OUt1 can be switched alone , they can be switched together
or OUT2 can be switched when OUT1 is already on .In the last
case , the voltage drop on OUT1 when charging OUT2 is
limited .
The external capacitor C
CP
connected to pin CP is used to
store the charge continuously delivered by the charge pump .
The voltage on this pin is limited to a maximum value V
CPmax
.
Both outputs are sourced with a constant current from C
CP
to
switch them on . In addition , the gates of the power FETs are
precharged from VCC to prevent C
CP
from being discharged
by a voltage on OUT1 or OUT2 which is still lower than
V
VCC
.The values of the output voltages are limited to
V
OUT1max
and V
OUT2max
The power FET on OUT1 is protected againts an
exceeded gate-source voltage by an internal zener diode.
Channel 1 allows to protect the n-channel power FET on
OUT1 under over current condition. The drain-source voltage
of the FET on OUT1 will be checked, if the channel 1 is
switched on. The internal error voltage threshold determines
the maximum drain-source voltage that allows the power FET
to stay in the on state. If the measured drain-source voltage
exceeds the internal error voltage threshold, the output of the
Over Current Protection Comparator (OCPC) is enabled. If
the output of the OCPC is active longer than t
OCdet
, the output
OUT1 is switched off .
After switching off the power FET on OUT1 by an over
current condition, the power FET can only be turned on again
by the input IN.
When switching off the power FETs their gate capacities
are discharged by a constant currennt I
OUToff
IF the input IN is disconnected, the MC33285 outputs
OUT1 and OUT2 are in the off state.
If overvoltage occurs on pin DRN for a time period longer
than t
LDdet
, then OUT2 is switched on for the time t
OUT2act
. In
overvoltage condition OUT1 is off if IN is below Vih.
Internal Zener Diode
An on-chip zener diode is placed between OUT1 and
SRC. Design guarantees that V
Z
> V
TH1
- zener clamping voltage between OUT1 and SRC :
V
TH1
< V
Z
< 20V
PWM capability
The CPIC2 is PWM capable on OUT2. The loss of charge
on Ccp when switching on OUT2 is refreshed until the start on
the next PWM cycle to a value which is sufficient to guarantee
the specified turn on behaviour.
The PWM capability is measured with a test circuit and
load conditions
- PWM cycle : period T = 20ms ; OUT2 is switched on from
10% to 90% of T .
- Test condition : V
IN
: ramps 2.5V to 5V according to PWM
cycle defined above.
Crosstalk between OUT1 and OUT2
If output OUT2 is switched on while OUT1 is already on,
the voltage drop that occurs on OUT1 is limited.
Voltage drop on OUT1 :
10V < V
VCC
< 20V : OUT1 not below V
VCC
+ 7V
7V < V
VCC
< 20V : OUT1 not below V
VCC
+ 7V
Each time OUT1 is switched on, a current ILCdet is
sourced out of pin SRC for the time tLCdet to check if there is
an external leakage current on that node in the application.
The high side switch on OUT1 is turned on only if the test is
successful."
MC33285
MOTOROLA
4
MC33285
Motorola reserves the right to make changes without further notice to any products herein to improve
reliability, function or design. Motorola does not assume any liability arising out of the application or use of any
product or circuit described herein ; neither does it convert any licence under its patent rights of others. Motorola
products are not authorized for use as components in life support devices or systems intended for surgical implant
into the body or intended to support or sustain life. Buyer agrees to notify Motorola of any such intended end use
whereupon Motorola shall determine availability and suitability of its products for the use intended. Motorola and
are registered trademarks of Motorola, Inc. Motorola, Inc. is an Equal Employment opportunity/Affirmative
Action Employer.
MC33285
MOTOROLA
5
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