STMICROELECTRONICS L9997

L9997ND

DUAL HALF BRIDGE DRIVER
HALF BRIDGE OUTPUTS WITH TYPICAL
RON = 0.7Ω
OUTPUT CURRENT CAPABILITY ±1.2A
OPERATING SUPPLY VOLTAGE RANGE 7V
TO 16.5V
SUPPLY OVERVOLTAGE PROTECTION
FUNCTION FOR VVS UP TO 40V
VERY LOW QUIESCENT CURRENT IN
STANDBY MODE < 1µA
CMOS COMPATIBLE INPUTS WITH HYSTERESIS
OUTPUT SHORT-CIRCUIT PROTECTION
THERMAL SHUTDOWN
REAL TIME DIAGNOSTIC: THERMAL OVERLOAD, OVERVOLTAGE
DESCRIPTION
The L9997ND is a monolithic integrated driver, in
BCD technology intended to drive various loads,
MULTIPOWER BCD TECHNOLOGY
SO20 (12+4+4)
ORDERING NUMBERS: L9997ND
L9997ND013TR
including DC motors. The circuit is optimized for
automotive electronics enviromental conditions.
BLOCK DIAGRAM
VS
DIAG
VS
11
1
EN
10
ENABLE
REFERENCE
BIAS
PROTECTION
FUNC TIONS
5V
VS
OUT1
IN1
12
19
DRIVER 1
M
VS
IN2
OUT2
9
DRIVER 2
2
GND
4...7, 14...17
April 1999
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L9997ND
ABSOLUTE MAXIMUM RATINGS
Symbol
Parameter
V VSDC
DC Supply Voltage
VVSP
Supply Voltage Pulse (T < 400ms)
IOUT
DC Output Current
VIN1,2
V EN
Value
Unit
-0.3 to 26
V
40
V
±1.8
A
DC Input Voltage
-0.3 to 7
V
Enable Input Voltage
-0.3 to 7
V
-0.3 to 7
V
VDIAG
DC Output Voltage
IOUT
DC Output Short-circuit Current -0.3V < VOUT < VS + 0.3V
internally limited
IDIAG
DC Sink Current -0.3V < VDG < 7V
internally limited
PIN CONNECTION (Top view)
VS
1
20
N.C.
OUT2
2
19
OUT1
N.C.
3
18
N.C.
GND
4
17
GND
GND
5
16
GND
GND
6
15
GND
GND
7
14
GND
N.C.
8
13
N.C.
IN2
9
12
IN1
EN
10
11
DIAG
D95AT166
PIN FUNCTIONS
N.
Name
1
VS
2
OUT2
3, 8, 13,
18,20
NC
4 to 7,
14 to 17
GND
Function
Supply Voltage
Channel 2: Push-Pull power output with intrinsic body diode
NC: Not Connected
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
12
IN1
Diagnostic: Open Drain Output that switches LOW if overvoltage or overtemperature is
detected
Input 1: Schmitt Trigger input with hysteresis (non-inverting signal control)
THERMAL DATA
Symbol
Value
Unit
TjTS
Thermal Shut-down Junction Temperature
Parameter
165
°C
TjTSH
Thermal Shut-down Threshold Hysteresis
25
K
50
K/W
15
K/W
Rth j-amb
Thermal Resistance Junction-Ambient
Rth j-pins
Thermal Resistance Junction-Pins
2
(1) With 6cm on board heatsink area.
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(1)
L9997ND
ELECTRICAL CHARACTERISTICS (7V < VS < 16.5V; -40°C < TJ < 150°C; unless otherwise specified.)
Symbol
Parameter
Test Condition
IVS_SB
Quiescent Current in Standby
Mode
VEN < 0.3V; VVS <16.5V; Tj < 85°(*)
VEN = 0; VVS = 14.5V; Tj = 25°C
Supply Current
EN = HIGH, IOUT1,2 = 0
IVS
VENL
Low Enable Voltage
VENH
High Enable Voltage
VENthh
Enable Threshold Hysteresis
IEN
Enable Input Current
Low Input Voltage
High Input Voltage
VIN1,2thh
Input Threshold Hysteresis
|IOUT1,2|
VDIAG
µA
µA
6
mA
1.5
V
6
V
250
µA
V
1.5
-3
2
Output Current Limitation
1.2
Diagnostic Output Drop
V
0
10
1
50
µA
µA
1.2
1.1
0.7
2.8
2.25
Ω
Ω
Ω
1.6
2.2
A
0.6
V
19
21
V
50
150
µs
IDIAG = 0.5mA, EN = HIGH
Overvoltage or Thermal Shutdown
17
See Fig. 2; VVS = 13.5V
Measured with 93Ω load
V
V
1
IOUT = ±0.8A; V VS = 7V; Tj = 125°C
IOUT = ±0.8A; VVS = 12V; Tj = 125°C
IOUT = ±0.8A; V VS = 12V; Tj = 25°C
Turn on Delay Time
90
10
3.5
ON-Resistance to Supply or
GND
tONLH
<1
<1
1
VIN = 0
VIN = 5V, EN = HIGH
Supply Overvoltage
Threshold
Unit
85
Input Bias Current
VVSOVth
Max.
2
VEN = 5V
VIN1,2L
RON OUT1,2
Typ.
3.5
VIN1,2H
IIN1,2
Min.
30
150
µs
Turn off Delay Time
10
100
µs
2
20
µs
tdHL
Rising Delay Time
115
250
µs
tdLH
Falling Delay Time
115
250
µs
trHS
Rise Time
30
100
µs
60
150
µs
25
100
µs
50
150
µs
tONHL
tOFFHL
tOFFLH
trLS
tfHS
Fall Time
tfLS
* 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 automotive 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
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L9997ND
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 RDSON increases with the junction temperature and decreases the output current. The power dissipation
in this condition can activate the thermal shutdown . In the case of output disable due to thermal overload the output remains disabled untill
the junction temperature decreases under the
thermal enable threshold.
Permanent short circuit condition with power dissipation leading to chip overheating and activation
of the thermal shut-down leads to the thermal oscillation. The junction temperature difference between the switch ON and OFF points is the thermal hysteresis of the thermal protection. This
hysteresis together with the thermal impedance
and ambient temperature determines the frequency of this thermal oscillation, its typical values are in the range of 10kHz.
The open drain diagnostic output needs an external pull-up resistor to a 5V supply. In systems
with several L9997ND the diagnostic outputs can
be connected together with a common pull-up resistor. The DIAG output current is internally limited.
Fig. 1 shows a typical application diagram for the
DC motor driving. To assure the safety of the circuit in the reverse battery condition a reverse protection diode D1 is necessary. The transient protection diode D2 must assure that the maximal
supply voltage V VS during the transients at the
VBAT line will be limited to a value lower than the
absolute maximum rating for VVS.
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 VEN < 0.3V. When
activating or disactivating the device by the enable input a wake-up time of 50µs is recommended.
For braking of the motor the status 2 is recommended. The reason for this recommendation is
that the device features higher threshold for initialisation of parasitic structures than in state 5.
The inputs IN1, IN2 features internal sink current
generators of 10µA, 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 function referred to the supply voltage VVS. This function 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 diagnostic output is ON.
The thermal shut-down disables the outputs (tristate) and activates the diagnostic when the junction 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 protected against short circuit to GND or VS, for supply voltages up to the overvoltage disable threshold.
The output power DMOS transistors works in linear mode for an output current less than 1.2A. Increasing the output load current (> 1.2A) the out-
Figure 1: Application Circuit Diagram.
Is
D1
5V
VBAT
47KΩ
CS
D2
VS
IDIAG1
DIAG1
OUT1
IIN1
CONTROL
LOGIC
IM
IN1
IIN2
IN2
IOUT1
L9997ND
M
VM
IEN
EN
OUT2
IOUT2
GND
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GND
L9997ND
Figure 2. Timing Diagram.
Standby Mode
Operating Mode
Overtemperature
or Overvoltage
Standby Mode
EN
IN1
IN2
DIAG
t dHL
t dLH
tONHL
t dLH
t dHL
t OFFLH
90%
OUT1 Tristate
Tristate
Tristate
10%
tr
tONLH
t dHL
tf
t dLH
t dHL
t dLH
t OFFHL
90%
Tristate
50%
OUT2 Tristate
Tristate
10%
tr
tf
Figure 3. Typical R ON - Characteristics of Source and Sink Stage
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L9997ND
Figure 4. Quiescent current in standby mode versus supply voltage.
Figure 5. ON-Resistance versus supply voltage.
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L9997ND
Figure 6. IOUT versus VOUT (pulsed measurement with TON = 500µs, TOFF = 500ms).
Figure 7. Test circuit.
100µF
12V
200nF
VS
10kΩ
EN
IN1
DIAG
L9997ND
IN2
V
EN
VIN1
5V
OUT1
15Ω
OUT2
15 Ω
VIN2
GND
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L9997ND
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L9997ND
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 parties 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.
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 1999 STMicroelectronics – Printed in Italy – All Rights Reserved
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