L9997ND
DUAL HALF BRIDGE DRIVER
HALF BRIDGE OUTPUTS WITH TYPICAL
R
ON
= 0.7
OUTPUT CURRENT CAPABILITY
1.2A
OPERATING SUPPLY VOLTAGE RANGE 7V
TO 16.5V
SUPPLY
OVERVOLTAGE
PROTECTION
FUNCTION FOR V
VS
UP TO 40V
VERY
LOW
QUIESCENT
CURRENT
IN
STANDBY MODE < 1
A
CMOS COMPATIBLE INPUTS WITH HYS-
TERESIS
OUTPUT SHORT-CIRCUIT PROTECTION
THERMAL SHUTDOWN
REAL TIME DIAGNOSTIC: THERMAL OVER-
LOAD, OVERVOLTAGE
DESCRIPTION
The L9997ND is a monolithic integrated driver, in
BCD technology intended to drive various loads,
including DC motors. The circuit is optimized for
automotive electronics enviromental conditions.
April 1999
OUT1
OUT2
GND
IN1
IN2
EN
DIAG
5V
10
1
12
9
2
19
11
4...7, 14...17
VS
VS
VS
VS
PROTECTION
FUNC TIONS
REFERENCE
BIAS
DRIVER 1
DRIVER 2
ENABLE
M
BLOCK DIAGRAM
SO20 (12+4+4)
ORDERING NUMBERS: L9997ND
L9997ND013TR
MULTIPOWER BCD TECHNOLOGY
1/9
ABSOLUTE MAXIMUM RATINGS
Symbol
Parameter
Value
Unit
V
VSDC
DC Supply Voltage
-0.3 to 26
V
V
VSP
Supply Voltage Pulse (T < 400ms)
40
V
I
OUT
DC Output Current
1.8
A
V
IN1,2
DC Input Voltage
-0.3 to 7
V
V
EN
Enable Input Voltage
-0.3 to 7
V
V
DIAG
DC Output Voltage
-0.3 to 7
V
I
OUT
DC Output Short-circuit Current -0.3V < V
OUT
< V
S
+ 0.3V
internally limited
I
DIAG
DC Sink Current -0.3V < V
DG
< 7V
internally limited
THERMAL DATA
Symbol
Parameter
Value
Unit
T
jTS
Thermal Shut-down Junction Temperature
165
C
T
jTSH
Thermal Shut-down Threshold Hysteresis
25
K
R
th j-amb
Thermal Resistance Junction-Ambient
(1)
50
K/W
R
th j-pins
Thermal Resistance Junction-Pins
15
K/W
(1) With 6cm
2
on board heatsink area.
V
S
OUT2
N.C.
GND
GND
GND
GND
N.C.
IN2
IN1
N.C.
GND
GND
GND
GND
N.C.
OUT1
N.C.
1
3
2
4
5
6
7
8
9
18
17
16
15
14
12
13
11
19
10
20
EN
DIAG
D95AT166
PIN CONNECTION (Top view)
PIN FUNCTIONS
N.
Name
Fun ction
1
VS
Supply Voltage
2
OUT2
Channel 2: Push-Pull power output with intrinsic body diode
3, 8, 13,
18,20
NC
NC: Not Connected
4 to 7,
14 to 17
GND
Ground: signal - and power - ground, heat sink
9
IN2
Input 2: Schmitt Trigger input with hysteresis (non-inverting signal control)
10
EN
Enable: LOW or not connected on this input switches the device into standby mode and the
outputs into tristate
11
DIAG
Diagnostic: Open Drain Output that switches LOW if overvoltage or overtemperature is
detected
12
IN1
Input 1: Schmitt Trigger input with hysteresis (non-inverting signal control)
L9997ND
2/9
ELECTRICAL CHARACTERISTICS (7V < V
S
<
16.5V; -40
C < T
J
< 150
C; unless otherwise specified.)
Symbol
Parameter
Test Condition
Min.
Typ.
Max.
Unit
I
VS_SB
Quiescent Current in Standby
Mode
V
EN
<
0.3V; V
VS
<16.5V; T
j
<
85
(*)
V
EN
= 0; V
VS
=
14.5V; T
j
= 25
C
<1
<1
90
10
A
A
I
VS
Supply Current
EN = HIGH, I
OUT1,2
= 0
2
6
mA
V
ENL
Low Enable Voltage
1.5
V
V
ENH
High Enable Voltage
3.5
6
V
V
ENthh
Enable Threshold Hysteresis
1
V
I
EN
Enable Input Current
V
EN
= 5V
85
250
A
V
IN1,2L
Low Input Voltage
1.5
V
V
IN1,2H
High Input Voltage
3.5
V
V
IN1,2thh
Input Threshold Hysteresis
1
V
I
IN1,2
Input Bias Current
V
IN
= 0
V
IN
= 5V, EN = HIGH
-3
2
0
10
1
50
A
A
R
ON OUT1,2
ON-Resistance to Supply or
GND
I
OUT
=
0.8A; V
VS
= 7V; T
j
= 125
C
I
OUT
=
0.8A; V
VS
= 12V; T
j
= 125
C
I
OUT
=
0.8A; V
VS
= 12V; T
j
= 25
C
1.2
1.1
0.7
2.8
2.25
|I
OUT1,2
|
Output Current Limitation
1.2
1.6
2.2
A
V
DIAG
Diagnostic Output Drop
I
DIAG
= 0.5mA, EN = HIGH
Overvoltage or Thermal Shut-
down
0.6
V
V
VSOVth
Supply Overvoltage
Threshold
17
19
21
V
t
ONLH
Turn on Delay Time
See Fig. 2; V
VS
= 13.5V
Measured with 93
load
50
150
s
t
ONHL
30
150
s
t
OFFHL
Turn off Delay Time
10
100
s
t
OFFLH
2
20
s
t
dHL
Rising Delay Time
115
250
s
t
dLH
Falling Delay Time
115
250
s
t
rHS
Rise Time
30
100
s
t
rLS
60
150
s
t
fHS
Fall Time
25
100
s
t
fLS
50
150
s
* Tested at 125
C and guaranteed by correlation
FUNCTIONAL DESCRIPTION
The L9997ND is a motor driver two half-bridge
outputs, intended for driving dc motors in automo-
tive systems. The basic function of the device is
shown in the Table 1.
Table 1. Table function.
Status
EN
IN1
IN2
OUT1
OUT2
DIAG
NOTE
1
L
X
X
Tristate
Tristate
OFF
Standby Mode
2
H
H
H
SRC
SRC
OFF
Recommended for braking
3
H
H
L
SRC
SNK
OFF
4
H
L
H
SNK
SRC
OFF
5
H
L
L
SNK
SNK
OFF
6
H
X
X
Tristate
Tristate
ON
Overvoltage or Overtemperature
L9997ND
3/9
The device is activated with enable input voltage
HIGH. For enable input floating (not connected)
or LOW the device is in Standby Mode. Very low
quiescent current is defined for V
EN
< 0.3V. When
activating or disactivating the device by the en-
able input a wake-up time of 50
s is recom-
mended.
For braking of the motor the status 2 is recom-
mended. The reason for this recommendation is
that the device features higher threshold for ini-
tialisation of parasitic structures than in state 5.
The inputs IN1, IN2 features internal sink current
generators of 10
A, disabled in standby mode.
With these input current generators the input level
is forced to LOW for inputs open. In this condition
the outputs are in SNK state.
The circuit features an overvoltage disable func-
tion referred to the supply voltage V
VS
. This func-
tion assures disabling the power outputs, when
the supply voltage exceeds the over voltage
threshold value of 19V typ. Both outputs are
forced to tristate in this condition and the diagnos-
tic output is ON.
The thermal shut-down disables the outputs (tris-
tate) and activates the diagnostic when the junc-
tion temperature increases above the thermal
shut-down threshold temperature of min. 150
C.
For the start of a heavy loaded motor, if the motor
current reaches the max. value, it is necessary to
respect the dynamical thermal resistance junction
to ambient. The outputs OUT1 and OUT2 are pro-
tected against short circuit to GND or V
S
, for sup-
ply voltages up to the overvoltage disable thresh-
old.
The output power DMOS transistors works in lin-
ear mode for an output current less than 1.2A. In-
creasing the output load current (> 1.2A) the out-
put transistor changes in the current regulation
mode, see Fig.6, with the typical output current
value below 2A. The SRC output power DMOS
transistors requires a voltage drop ~3V to activate
the current regulation. Below this voltage drop is
the device also protected. The output current heat
up the power DMOS transistor, the R
DSON
in-
creases with the junction temperature and de-
creases the output current. The power dissipation
in this condition can activate the thermal shut-
down . In the case of output disable due to ther-
mal overload the output remains disabled untill
the junction temperature decreases under the
thermal enable threshold.
Permanent short circuit condition with power dis-
sipation leading to chip overheating and activation
of the thermal shut-down leads to the thermal os-
cillation. The junction temperature difference be-
tween the switch ON and OFF points is the ther-
mal hysteresis of the thermal protection. This
hysteresis together with the thermal impedance
and ambient temperature determines the fre-
quency of this thermal oscillation, its typical val-
ues are in the range of 10kHz.
The open drain diagnostic output needs an exter-
nal pull-up resistor to a 5V supply. In systems
with several L9997ND the diagnostic outputs can
be connected together with a common pull-up re-
sistor. The DIAG output current is internally lim-
ited.
Fig. 1 shows a typical application diagram for the
DC motor driving. To assure the safety of the cir-
cuit in the reverse battery condition a reverse pro-
tection diode D
1
is necessary. The transient pro-
tection diode D
2
must assure that the maximal
supply voltage V
VS
during the transients at the
V
BAT
line will be limited to a value lower than the
absolute maximum rating for V
VS
.
M
V
S
5V
C
S
IN1
IN2
GND
DIAG1
CONTROL
LOGIC
47K
IDIAG1
IIN1
IIN2
IEN
EN
D
2
V
BAT
D
1
I
s
L9997ND
OUT1
IM
VM
IOUT1
IOUT2
OUT2
GND
Figure 1: Application Circuit Diagram.
L9997ND
4/9
EN
IN1
IN2
DIAG
OUT1
OUT2
Standby Mode
Operating Mode
Overtemperature
or Overvoltage
Standby Mode
t r
f
t
t dLH
t dHL
tOFFLH
Tristate
90%
t r
90%
50%
10%
f
t
10%
tONHL
Tristate
t dHL
tOFFHL
t dLH
t dHL
t dLH
t dHL
Tristate
Tristate
Tristate
Tristate
tONLH
t dLH
Figure 2. Timing Diagram.
Figure 3. Typical R
ON
- Characteristics of Source and Sink Stage
L9997ND
5/9
Figure 5. ON-Resistance versus supply voltage.
Figure 4. Quiescent current in standby mode versus supply voltage.
L9997ND
6/9
OUT1
OUT2
IN1
IN2
EN
GND
DIAG
10k
200nF
100
F
12V
V
EN
15
5V
IN1
V
IN2
V
L9997ND
15
VS
Figure 7. Test circuit.
Figure 6. I
OUT
versus V
OUT
(pulsed measurement with T
ON
= 500
s, T
OFF
= 500ms).
L9997ND
7/9
L9997ND
8/9
Information furnished is believed to be accurate and reliable. However, STMicroelectronics assumes no responsibility for the consequences
of use of such information nor for any infringement of patents or other rights of third parti es which may result from its use. No license is
granted by implication or otherwise under any patent or patent rights of STMicroelectronics. Specification mentioned in this publication are
subject to change without notice. This publication supersedes and replaces all information previously supplied. STMicroelectronics products
are not authorized for use as critical components in life support devices or systems without express written approval of STMicroelectronics.
The ST logo is a registered trademark of STMicroelectronics
1999 STMicroelectronics Printed in Italy All Rights Reserved
STMicroelectronics GROUP OF COMPANIES
Australia - Brazil - Canada - China - France - Germany - Italy - Japan - Korea - Malaysia - Malta - Mexico - Morocco - The Netherlands -
Singapore - Spain - Sweden - Switzerland - Taiwan - Thailand - United Kingdom - U.S.A.
http://www.st.com
L9997ND
9/9
PDF 
ZIP