STMICROELECTRONICS STPIC44L02

STPIC44L02
4 CHANNEL SERIAL AND PARALLEL
LOW SIDE PRE-FET DRIVER
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4-CHANNEL SERIAL-IN PARALLEL-IN LOW
SIDE PRE-FET DRIVER
DEVICES ARE CASCADABLE
INTERNAL 55V INDUCTIVE LOAD CLAMP
AND VGS PROTECTION CLAMP FOR
EXTERNAL POWER FETS
INDEPENDENT SHORTED-LOAD AND
SHORT-TO-BATTERY FAULT DETECTION
ON ALL GATE TERMINALS
INDEPENDENT OFF-STATE OPEN-LOAD
FAULT SENSE
OVER-BATTERY-VOLTAGE LOCKOUT
PROTECTION AND FAULT REPORTING
UNDER-BATTERY VOLTAGE LOCKOUT
PROTECTION
ASYNCRONOUS OPEN-GATE FAULT FLAG
DEVICE OUTPUT CAN BE WIRED OR WITH
MULTIPLE DEVICES
FAULT STATUS RETURNED THROUGH
SERIAL OUTPUT TERMINAL
INTERNAL GLOBAL POWER-ON RESET OF
DEVICE AND EXTERNAL RESET TERMINAL
HIGH IMPEDANCE CMOS COMPATIBLE
INPUTS WITH HYSTERESIS
TRANSITION FROM THE GATE OUTPUT TO
A LOW DUTY CYCLE PWM MODE WHEN A
SHORTED LOAD FAULT OCCURS
DESCRIPTION
The STPIC44L02 is a low-side predriver that
provides serial and parallel input interfaces to
control four external FET power switches.
It is mainly designed to provide low-frequency
switching, inductive load applications such as
solenoids and relays. Fault status is available in a
serial-data format. Each driver channel has
independent off-state open-load detection and
on-state shorted load short to battery detection.
The STPIC44L02 offers a battery over voltage and
undervoltage detection and shutdown. If a fault
occurs while using the STPIC44L02, the channel
transitates into a low duty cycle, pulse width
modulated (PWM) signal as long as the fault is
present.
These devices provide control of output channels
through a serial input interface or a parallel input
interface. A command to enable the output from
July 2003
SOP
either interface enables the respective channels
gate output to the external FET. The serial
interface is recommended when the number of
signals between the control device and the
predriver are minimized and the speed of
operation is not critical. In applications where the
predriver must respond very quickly or
asynchronously, the parallel input interface is
recommended.
For serial operation, the control device must
transitate CS from high to low to activate the serial
input interface. When this occurs, SDO, is
enabled, fault data is latched into the serial
interface, and the fault flag is refreshed. Data is
clocked into the serial registers on low to high
transitions of SCLK through SDI. Each string of
data must consist of at least four bits of data. In
applications where multiple devices are cascaded
together, the string of data must consist of four bits
for each device. A high data bit turns the
respective output channel on and a low data bit
turns it off. Fault data for the device is clocked out
of SDO as serial input data is clocked into the
device. Fault data consists of fault flags for
shorted load and open load flags (bits 0-3) for
each of the four output channels. Fault register
bits are set or cleared asynchronously to reflect
the current state of the hardware. A fault must be
present when CS is transitated from high to low to
be captured and reported in the serial fault data.
New faults cannot be captured in the serial
register when CS is low. CS must be transitated
high after all of the serial data has been clocked
into the device. A low to high transition of CS
transfers the last four bits of serial data to the
1/21
STPIC44L02
output buffer that puts SDO in a high impedance
state and clears and reenables the fault register.
The STPIC44L02 was designed to allow the serial
input interfaces of multiple devices to be cascated
together to simplify the serial interface of the
controller. Serial input data flows through the
device and is transferred out SDO following the
fault data in cascaded configurations.
For parallel operation, data is transferred directly
from the parallel input interface IN0-IN3 to the
respective GATE(0-3) output asynchronously.
SCLK or CS is not required for parallel control. A 1
on the parallel input turns the respective channel
on, where as a 0 turns it off. Note that either the
serial input interface or the parallel input interface
can enable a channel. Under parallel operation,
fault data must still be collected through the serial
data interface.
The predriver monitors the drain voltage for each
channel to detect shorted load or open load fault
conditions, in the on and off state respectively.
These devices offer the option of using an
internally generated fault reference voltage or an
externally supplied fault reference voltage through
VCOMP for fault detection. The internal fault
reference is selected by connecting VCOMPEN to
GND and the external reference is selected by
connecting VCOMPEN to VCC. The drain voltage is
compared to the fault reference when the channel
is turned on to detect shorted load conditions and
when the channel is off to detect open load
conditions. If a fault occurs, the channel
transitates into a low duty cycle, pulse width
modulated (PWM) signal as long as the fault is
present. Shorted load fault conditions must be
present for at least the shorted load deglicth time,
t(STBDG), to be flagged as a fault. A fault flag is
sent to the control device as well as the serial fault
register bits. More detail on fault detection
operation is presented in the device operation
section of this datasheet.
The device provides protection from over battery
voltage and under battery voltage conditions
irrespective of the state of the output channels.
When the battery voltage is greater than the
overvoltage threshold or less than the
undervotlage threshold, all channels are disabled
and a fault flag is generated. Battery voltage faults
are not reported in the serial fault data. The
outputs return to normal operation once the
battery voltage fault has been corrected. When an
over battery/under battery voltage condition
occurs, the device reports the battery fault, but
disables fault reporting for open and shorted load
conditions. Fault reporting for open and shorted
load conditions are reenabled after the battery
fault condition has been corrected.
This device provides inductive transient protection
on all channels. The drain voltage is clamped to
protect the FET. The clamp voltage is defined by
the sum of VCC and turn on voltage of the external
FET. The predriver also provides a gate to source
voltage (VGS) clamp to protect the gate source
terminals of the power FET from exceeding their
rated voltages. An external active low RESET is
provided to clear all register and flags in the
device. GATE(0-3) outputs are disabled after
RESET has been pulled low.
The device provide pull-down resistors on all
inputs except CS and RESET. A pull-up resistor is
used on CS and RESET.
ORDERING CODES
2/21
Type
Package
Comments
STPIC44L02PTR
SSOP24 (Tape & Reel)
1350 parts per reel
STPIC44L02
Figure 1 : Schematic Diagram
3/21
STPIC44L02
PIN DESCRIPTION
PIN No
SYMBOL
I/O
NAME AND FUNCTION
1
FLT
I
2
VCOMPEN
I
3
VCOMP
I
4
5
6
7
8
IN0
IN1
IN2
IN3
CS
I
Fault Flag. FLT is a logic level open-drain output that provides a real time fault flag for
shorted-load, open-load, over-battery voltage, under-battery voltage faults. The
device can be ORed with FLT terminals on other devices for interrupt handling. FLT
requires an external pull-up resistor.
Fault reference voltage select. VCOMPEN selects the internally generated fault
reference voltage (0) or an external fault reference (1) to be used in the shorted and
open load fault detection circuitry.
Fault reference voltage. VCOMP provides an external fault reference voltage for the
shorted-load and open load fault detection circuitry.
Parallel gate driver. IN0 trough In3 are real-time controls for the gate pre drive
circuitry. They are CMOS compatible with hysteresis.
9
SDO
O
10
SDI
I
11
SCLK
I
12
VCC
I
13
14
16
19
21
15
17
18
20
22
GND
DRAIN0
DRAIN1
DRAIN2
DRAIN3
GATE0
GATE1
GATE2
GATE3
RESET
I
I
Ground
FET drain inputs. DRAIN0 through DRAIN3 are used for both open load and short
circuit fault detection at the drain of the external FETs. They are also used for
inductive transient protection.
O
Gate drive output. GATE0 through GATE3 outputs are derived from the VBAT supply
voltage. Internal clamps prevent voltages on these nodes from exceeding the VGS
rating of most FETs.
I
23
24
NC
VBAT
Reset. A high-to low transition of RESET clears all registers and flags. Gate outputs
turn off and the FLT flag is cleared.
Not Connected
Battery Supply Voltage
4/21
I
I
Chip select. A high to low transition on CS enables SDO, latches fault data into the
serial interface, and refreshes FLT. When CS is high, the fault register can change
fault status. On the falling edge of CS, fault data is latched into the serial output
register and transferred using SDO and SCLK. On a low to high transition of CS,
serial data is latched in to the output control register.
Serial data output. SDO is a 3-state output that transfers fault data to the controlling
device. It also passes serial input data to the next stage for cascaded operation. SDO
is taken to a high-impedance state when CS is in a high state.
Serial data input. Output control data is clocked into the serial register through SDI. A
1 on SDI commands a particular gate output on and a 0 turns it off.
Serial clock. SCLK clocks the shift register. Serial data is clocked into SDI and serial
fault data is clocked out of SDO on the falling edge of the serial clock.
Logic Supply Voltage
STPIC44L02
Figure 2 : Pin Configuration
ABSOLUTE MAXIMUM RATINGS
Symbol
Parameter
Value
Unit
V
VCC
Logic Supply Voltage (See Note 1)
-0.3 to 7
VBAT
Battery Supply Voltage
-0.3 to 60
V
VI
Logic Input Voltage Range
-0.3 to 7
V
VO
Output Voltage (SDO and FLT)
-0.3 to 7
V
VO
Output Voltage
-0.3 to 15
V
VI
Logic Input Voltage Range
-0.3 to 7
V
VDS
Drain to Source Voltage
-0.3 to 60
V
TC
Operating Case Temperature Range
-40 to +125
°C
TJ
Maximum Junction Temperature
150
°C
-40 to +150
°C
Tstg
Storage Temperature Range
Absolute Maximum Ratings are those values beyond which damage to the device may occur. Functional operation under these condition is
not implied.
Note 1: All voltage value are with respect to GND
RECOMMENDED OPERATING CONDITIONS
Symbol
Parameter
VCC
Logic Supply Voltage
VBAT
Battery Supply Voltage
VIH
High Level Input Voltage
VIL
Min.
Min.
Max.
Unit
4.5
5
5.5
V
8
24
V
0.85VCC
VCC
V
0.15VCC
Low Level Input Voltage
0
ts
Set-up Time, SDI High Before SCLK ↑
10
th
Hold Time, SDI High After SCLK ↑
10
TC
Operating Case Temperature
-40
V
ns
ns
125
°C
5/21
STPIC44L02
ELECTRICAL CHARACTERISTICS OVER RECOMMENDED OPERATING FREE-AIR
TEMPERATURE RANGE (unless otherwise specified.)
Symbol
Parameter
Test Conditions
Min.
Typ.
Max.
Unit
IBAT
Supply Current
All Outputs OFF,
VBAT = 12V
50
150
250
µA
ICC
Supply Current
All Outputs OFF,
VBAT = 5.5V
0.5
1.5
3
mA
(see figure 21)
32
34
36
V
0.1
0.3
0.5
V
4.1
4.8
5.4
V
50
150
300
mV
13.5
V
V(ovsd)
Vhys(ov)
V(uvsd)
Vhys(uv)
VG
IO(H)
IO(L)
V(stb)
Vhys(stb)
Over Battery Voltage
Gate Disabled
Shutdown
Over Battery Voltage Reset
Hysteresys
Under Battery Voltage
Gate Disabled
Shutdown
Under Battery Voltage
Reset Hysteresys
Gate Drive Voltage
VBAT = 8 to 24V
IO = 100µA
VBAT = 5.5 to 8V
IO = 100µA
(see figure 20)
Maximum Current Output
VO = GND
For Drive Terminal Pull-Up
Maximum Current Output
VO = 7V
For Drive Terminal
Pull-Down
Short to Battery, Shorted
VCOMPEN = L
Load, Open Load Detection
Voltage
Short to Battery Hysteresys
Open Load OFF State
Detection Voltage
Threshold
Vhys(open) Open Load Hysteresys
Open Load Off State
II(open)
Detection Current
VD(open)
7
8
V
0.5
5
1.8
2.5
mA
0.5
1.2
2.5
mA
1.1
1.25
1.4
V
30
VCOMPEN = L
1.1
1.25
mV
1.4
60
VDRAIN = VREF = 1.25V
30
60
V
mV
80
µA
VDRAIN = 24V
(see figure 24)
250
µA
II(PU)
Input Pull-up Current
VCC = 5V
VI = 0
10
µA
II(PD)
Input Pull-down Current
VCC = 5V
VI = 5V
10
µA
Vhys
Input Voltage Hysteresys
VCC = 5V
0.6
High Level Serial Output
Voltage
Low Level Serial Output
Voltage
3-State Current Serial Data
Output
Fault Interrupt Output
Voltage
Fault External Reference
Voltage
Output Clamp Voltage
IO = 1mA
0.8VCC
VO(SH)
VO(SL)
IOZ(SD)
VO(CFLT)
VI(COMP)
VC
6/21
IO = 1mA
VCC = 0 to 5.5V
-10
IO = 1mA
VCOMPEN = H
dc < 1%
0.85
47
V
V
0.1
0.4
V
1
10
µA
0.1
0.5
V
3
V
63
V
1
tW = 100µs
1.1
55
STPIC44L02
SWITCHING CHARACTERISTICS (VCC=5V, VBAT=5V, TC= 25°C, unless otherwise specified.)
Symbol
Parameter
t(STBFM)
(see figures 16, 17)
60
µs
(see figures 16, 17)
12
µs
C(gate) = 400pF
3.5
µs
C(gate) = 400pF
4
µs
tr1
Short to Battery, Shorted
Load, Open Load Fault
Mask Time
Short to Battery, Shorted
Load, Deglitch Time
Propagation Turn-On Delay
Time, CS or IN0-IN3 to
Gate0-Gate3
Propagation Turn-Off Delay
Time, CS or IN0-IN3 to
Gate0-Gate3
Rise Time, Gate0-Gate3
C(gate) = 400pF
1.5
µs
tf1
Fall Time, Gate0-Gate3
C(gate) = 400pF
2
µs
f(SCLK)
Serial Clock Frequency
trf(SB)
Refresh Time Short to
(see figure 16)
Battery
Refresh pulse width Short
(see figure 16)
to Battery
Setup Time CS ↓ to SCLK ↓ (see note 1)
t(STBDG)
tPLH
tPHL
tW)
tsu1
tpd1
tpd2
tpd3
Propagation Delay Time CS
to SDO Valid
Propagation Delay Time
SCLK to SDO Valid
Propagation Delay Time CS
to SDO 3-State
tr2
Rise Time, SDO 3-State to
SDO Valid
tf2
Fall Time, SDO 3-State to
SDO Valid
tr3
Rise Time, FLT
tf3
Rise Time, FLT
Test Conditions
Min.
Typ.
Max.
10
RL = 10KΩ
(see figure 6)
RL = 10KΩ
(see figure 6)
RL = 10KΩ to GND
Over Battery Fault
RL = 10KΩ to GND
No Fault
RL = 10KΩ
(see figure 9)
RL = 10KΩ
(see figure 9)
Unit
MHz
10
ms
68
µs
(see figure 4)
10
ns
CL = 200pF
40
ns
20
ns
2
µs
30
ns
CL = 50pF
CL = 200pF
(see figure 7)
CL = 200pF
(see figure 8)
CL = 50pF
20
ns
1.2
µs
CL = 50pF
15
ns
Note 1: The td1 is referred to the falling edge of the first clock after the CS falls down
7/21
STPIC44L02
Figure 3 : Switching Time
Figure 4 : Setup Time CS ↓ to SCLK ↓
8/21
STPIC44L02
Figure 5 : Propagation Delay Time
Figure 6 : Propagation Delay Time
Figure 7 : SDO Switching Time
9/21
STPIC44L02
Figure 8 : SDO Switching Time
Figure 9 : FLT Switching Time
PRINCIPLES OF OPERATION
SERIAL DATA OPERATION
The STPIC44L02 offers serial input interface to
the microcontroller to transfer control data to the
predriver and fault data back to the controller. The
serial input interface consists of:
SCLK - Serial Clock
CS - Chip Select
SDI - Serial Data Input
SDO - SeriaL Data Output
Serial data is shifted into the least significant bit
(LSB) of the SDI shift register on the rising edge of
the first SCLK after CS has transitated from 1 to 0.
The CS must be transitated from 1 to 0 before the
falling edge of the first clock (see note 1).
Four clock cycles must occur before CS
transitates high for a proper control of the outputs.
Less than four clock cycles result in fault data
being latched into the output control buffer.
Eight bits data can be shifted into the device, but
the first 4 bits shifted out are always the fault data
and the last 4 bits shifted in are always the output
control data. A low-to-high transition on CS
10/21
latches the contents of the serial shift register into
the output control register. A logic 0 input to SDI
turns off the corresponding parallel output and a
logic 1 input turns the output on (see figure 10).
Data is shifted out of SDO on the falling edge of
SCLK. The MSB of fault data is available after CS
is transitated low. The remaining 3 bits of fault
data are shifted out in the following three clock
cycles. Fault data is latched into the serial register
when CS is transitated low. A fault must be
present on the high to low transition of CS to be
captured by the device. The CS input must be
transitated to a high state after the last bit of serial
data has been clocked into the device. The rising
edge of CS inhibit SDI puts SDO into a high
impedance state, latches the 4 bits of serial data
into the output control register, and clears and
reenables the serial fault registers (see figure 11).
When a shorted load condition occurs, the device
automatically retries the output and the fault clears
after the fault condition has been corrected.
STPIC44L02
Figure 10 : Serial Programming Example
Figure 11 : 8-Bit Serial Programming Example (single device)
11/21
STPIC44L02
Figure 12 : 8-Bit Serial Programming Example (two predrivers cascated)
Figure 13 : Fault Reading Example
PARALLEL INPUT DATA OPERATION
In addition to the serial interface the STPIC44L02
also provides a parallel interface to the
microcontroller. The output turns on when either
the parallel or the serial interface make it turn on.
The parallel data terminals are real time control
inputs for the outputs drivers. SCLK and CS are
not required to transfer parallel input data to the
output buffer. Fault data must be read over the
serial data bus as described in the serial data
operation section of this datasheet (see figure 13).
The parallel input must be transitated low and then
high to clear and reenable a gate output after it
has been disabled due to a shorted load fault
condition.
CHIPSET PERFORMANCE UNDER FAULT
CONDITIONS
The STPIC44L02 and power FET arrays are
designed for normal operation over a battery
12/21
voltage range of 8V to 24V with load fault
detection from 4.8V to 34V. It offers onboard fault
detection to handle a variety of faults that may
occur within a system. The circuits primary
function is to prevent damage to the load and the
power FETs in the event that a fault occurs.
Note that unused DRAIN0-DRAIN3 inputs must
be connected to VBAT through a pull-up resistor to
prevent false reporting of open load fault
conditions. The circuitry detects the fault, shuts off
the output to the FET and reports the fault to the
microcontroller. The primary faults under
consideration are:
1) Shorted Load
2) Open Load
3) over battery voltage shutdown
4) Under battery voltage shutdown.
SHORTED LOAD FAULT CONDITION
STPIC44L02
The STPIC44L02 monitors the drain voltage of
each channel to detect shorted load conditions.
The onboard deglitch timer starts running when
the gate output to the power FET transitates from
the off state to the on state. The timer provides a
60µs deglitch time, t(STBFM), to allow the drain
voltage to stabilize after the power FET has been
turned on (see figure 16 and 17).
The deglitch delay time is only enabled for the first
60µs after the FET has been turned on. After the
deglitch delay time, the drain voltage is checked to
verify that it is less than the fault reference
voltage. When it is greater than the reference
voltage for at least the short to battery deglitch
time, t(STBDG) FLT flags the microcontroller that a
fault condition exists and gate output is
automatically shut off until the error condition has
been corrected.
An overheating condition on the FET occurs when
the controller continually tries to reenable the
output under shorted load fault conditions. When a
shorted load fault is detected, the gate output is
transitated into a low duty cycle PWM signal to
protect the FET from overheating. The PWM rate
is defined as t(SB) and the pulse width is defined
as tW. The gate output remains in this state until
the fault has been corrected or until the controller
disables the gate output.
The microcontroller can read the serial port on the
predriver to isolate the channel that reported the
fault condition.
Fault bits 0-3 distinguish faults for each of the
output channels. When a shorted load occurs, the
STPIC44L02 automatically retries the output and
the fault clears after the fault condition has been
corrected. Figure 16 illustrates operation after a
gate output has been turned on. The gate to the
power FET is turned on and the deglitch timer
starts running. Under normal operation, T1 turns
on and the drain operates below the reference
point set at U1. The output of U1 is low and a fault
condition is not flagged.
Figure 14 : Open Load Test Circuit
13/21
STPIC44L02
Figure 15 : Normal Operation
Figure 16 : Shorted Load Condition (Deglitch Time)
OPEN LOAD
The STPiC44L02 monitors the drain of each
power FET for open circuit conditions that may
exist. The 60µA current source is provided to
monitor open load fault conditions. Open-load
faults are only detected when the power FET is
turned off. When load impedance is open or
substantially high, the 60µA current source has
adequate drive to pull the drain of T1 below the
fault reference threshold on the detection circuit.
14/21
Unused DRAIN0-DRAIN3 inputs must be
connected to VBAT through a pull-up resistor to
prevent false reporting of open-load fault
conditions. The on-board deglitch timer starts
running when the STPiC44L02, gate output to the
power FET transitates to the off state. The timer
provides a 60ms deglitch time, T(STBFM), to allow
the drain voltage to stabilize after the powerFET
has been turned off. The deglitch time is only
enabled for the first 60ms after the FET has been
STPIC44L02
turned off. After the deglitch delay time, the drain
is checked to verify that it is greater than the fault
reference voltage. When it is less than the
reference voltage, a fault is flagged to the
microcontroller through FLAT that an open-load
fault condition exists. The microcontroller can then
read the serial port on the STPiC44L02 to isolate
the channel that reported the fault condition. Fault
bits 0-3 distinguish faults for each of the output
channels. Figures 18 and 19 illustrate the
operation of the open-load detection circuit. This
feature provides useful information to the
microcontroller to isolate system failures and warn
the operator that a problem exists. Examples of
such applications would be a warning that a light
bulb filament may be open, solenoid coils may be
open, etc.
Figure 17 : Open Load Short Circuit test Circuitry
Figure 18 : Normal Condition Driving Load
15/21
STPIC44L02
Figure 19 : Open Load ConditionTime
OVER-BATTERY-VOLTAGE SHUTDOWN
The STPIC44L02 monitors the battery voltage to
prevent the power FETs turning on in the event
that the battery voltage is too high. This condition
may occur due to voltage transients resulting from
a loose battery connection. The TPIC44L02 turns
the power FET off when the battery voltage is
above 34V to prevent possible damage to the load
and the FET. GATE(0-3) output goes back to
normal operation after the overvoltage condition
has been corrected. An over-battery-voltage fault
is flagged to the controller through FLT. The
over-battery-voltage fault is not reported in the
serial fault word. When an over voltage condition
occurs, the device reports the battery fault, but
disables fault reporting for open and shorted-load
conditions. Fault reporting for open and
shorted-load conditions are re-enabled after the
battery fault condition has been corrected. When
the fault condition is removed before the CS signal
transitates low, the fault condition is not captured
in the serial fault register. The fault flag resets on a
high-to-low transition of CS providing that no other
faults are present in the device. Figure 21
illustrates the operation of the over-battery voltage
detection circuit.
Figure 20 : Under Battery Shutdown
UNDER-BATTERY-VOLTAGE SHUTDOWN
The STPIC44L02 monitors the battery voltage to
prevent the power FETs from being turned on in
the event that the battery voltage is too low. When
the battery voltage is below 4.8V, then
16/21
GATE0-GATE3 may not provide sufficient gate
voltage to the power FETs to minimize the
on-resistance that could result in a thermal stress
on the FET. The output goes back to normal
operation after the under voltage condition has
STPIC44L02
been corrected. An under-battery-voltage fault is
flagged to the controller through FLT. The
under-battery voltage fault is not reported in the
serial fault word. When an under-battery-voltage
condition occurs, the device reports the battery
fault but disables fault reporting for open and
shorted load conditions. When the fault condition
is removed before the CS signal transitates low,
the fault condition is not captured in the serial fault
register. The fault flag resets on a high-to-low
transition of CS providing that no other faults are
present in the device. Figure 21 illustrates the
operation of the under voltage detection circuit.
Figure 21 : Over Battery Shutdown
INDUCTIVE VOLTAGE TRANSIENTS
A typical application for the pre driver/power FET
circuit is to switch inductive loads. When an
inductive load is switched off, a large voltage spike
can occur. These spikes can exceed the
maximum VDS rating for the external FET and
damage the device when the proper protection is
not in place. The FET can be protected from these
transients through a variety of methods using
external components.
The STPIC44L02 offers that protection in the form
of a zener diode stack connected between the
DRAIN input and GATE output (see figure 22).
Zener diode Z1 turns the FET on to dissipate the
transient energy. GATE diode Z2 is provided to
prevent the gate voltage from exceeding 13V
during normal operation and transient protection.
Figure 22 : Switching Time
EXTERNAL FAULT REFERENCE INPUT
The STPIC44L02 compares each channel drain
voltage to a fault reference to detect shorted-load
and open-load conditions. The user has the option
of using the internal generated 1.25V fault
reference or providing an external reference
voltage through VCOMP. The internal reference is
selected by connecting VCOMPEN to GND and
VCOMP is selected by connecting VCOMPEN to VCC
(see Figure 23). Proper layout techniques should
be used in the grounding network for the VCOMP
circuit on the STPIC44L02. The ground for the
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STPIC44L02
predriver and VCOMP network should be
connected to a Kelvin ground if available;
otherwise, they should make single-point contact
back to the power ground of the FET array.
Improper grounding techniques can result in
inaccuracies in detecting faults.
Figure 23 : External Reference Selection
VREF
VCOMPEN
1.25V
VCOMP
1
TYPICAL PERFORMANCE CHARACTERISTICS (unless otherwise specified Tj = 25°C)
Figure 24 : Open Load Off State Detection
Current
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0
STPIC44L02
SSOP24 MECHANICAL DATA
mm.
inch
DIM.
MIN.
TYP
MAX.
A
MIN.
TYP.
MAX.
2
A1
0.05
A2
1.65
b
0.079
0.002
1.75
1.85
0.065
0.22
0.38
0.009
0.015
c
0.09
0.25
0.004
0.010
D
7.9
8.2
8.5
0.311
0.323
0.335
E
7.4
7.8
8.2
0.291
0.307
0.323
E1
5.00
5.3
5.6
0.197
0.209
0.220
e
0.069
0.65 BSC
K
0˚
L
0.55
A
0.073
0.0256 BSC
0.75
8˚
0˚
8˚
0.95
0.022
0.030
0.037
A2
A1
b
K
e
L
E
c
D
E1
PIN 1 IDENTIFICATION
1
0053237/C
19/21
STPIC44L02
Tape & Reel SSOP24 MECHANICAL DATA
mm.
inch
DIM.
MIN.
A
MAX.
MIN.
330
13.2
TYP.
MAX.
12.992
C
12.8
D
20.2
0.795
N
60
2.362
T
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TYP
0.504
22.4
0.519
0.882
Ao
8.4
8.6
0.331
0.339
Bo
8.7
8.9
0.343
0.351
Ko
2.9
3.1
0.114
0.122
Po
3.9
4.1
0.153
0.161
P
11.9
12.1
0.468
0.476
STPIC44L02
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. Specifications
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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