1
Features
Gate
Driver
Latch
V
REF
Control
Logic
V
CC
OUT
SENSE+
SENSE
CLI
Gnd
FLAG
CTRL
V
T
V
T
s
P Compatible Inputs
s
Adjustable Current Limit
Thresholds
s
External Sense Resistor
s
Flag Signal to Indicate
Output Status
Package Options
8L PDIP & SO Narrow
CS8312
IGBT Ignition Predriver
with Dynamic Current Regulation
1
FLAG
SENSE+
SENSE
Gnd
V
CC
CTRL
CLI
OUT
Description
Block Diagram
Absolute Maximum Ratings
The CS8312 is a bipolar micropro-
cessor interface IC designed to
drive an IGBT (or logic level
MOSFETs) powering large induc-
tive loads in harsh operating envi-
ronments. The ICs dynamic cur-
rent limit function lets the micro-
processor adjust the current limit
threshold to the real time needs of
the system.
CLI, the current limit input, sets the
current limit for the IGBT high or
low as directed by the system
microprocessor. CLI also raises and
lowers the threshold on the diag-
nostic FLAG output signal. The
FLAG output signals the micropro-
cessor when the current level
approaches current limit on the
IGBT. The CTRL input enables the
FLAG function.
CS8312
Supply Voltage.................................................................................-0.3V to +12V
Digital Input Currents....................................................................................2mA
Internal Power Dissipation (T
A
= 25C) .................................................700mW
Junction Temperature Range.....................................................-40C to +150C
Storage Temperature Range ......................................................-55C to +165C
Lead Temperature Soldering
Wave Solder(through hole styles only).............10 sec. max, 260C peak
Reflow (SMD styles only).............60 sec. max above 183C, 230C peak
Electrostatic Discharge (Human Body Model) ............................................2kV
A Company
Rev. 4/7/97
Cherry Semiconductor Corporation
2000 South County Trail, East Greenwich, RI 02818
Tel: (401)885-3600 Fax: (401)885-5786
Email: info@cherry-semi.com
Web Site: www.cherry-semi.com
2
Electrical Characteristics 7V V
CC
10V; -40C T
A
+125C; unless otherwise specified
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
CS8312
s General
Power Supply
7
10
V
including Ripple Voltage
Supply Ripple Frequency
10
60
kHz
Differential Ground Voltage
DC SENSE- to Gnd
-0.1
1.0
V
AC SENSE- to Gnd
-0.2
0.6
V
Differential Ground Frequency
10
60
kHz
Quiescent Current, I
Q
Turn On
V
CTRL
=5.5V
15
mA
Turn Off
V
CTRL
=-0.3V
5
mA
Supply Voltage Rejection
V
CTRL
=5.5V
30
dB
Differential Ground
V
CTRL
=5.5V
30
dB
Rejection Ratio
Differential Ground Current
V
CTRL
= -0.3V
3
mA
Ratio
(V
SENSE-
-V
Gnd
)DC=1V
(V
SENSE-
-V
Gnd
)AC=0.6V
Unity Gain Bandwidth
V
CTRL
=5.5V
400
kHz
Clamp Voltage
V
CTRL
=5.5V; I
OUT
=1mA
5.5
V
Output Off Voltage
V
CTRL
=-0.3V; I
OUT
=10A
0.5
V
V
CTRL
=-0.3V; I
OUT
=200A
1.2
V
Turn On Delay
CTRL increasing
30
us
Turn Off Delay
CTRL decreasing
30
us
s Control Function
Input Voltage Range
I
CTRL
=2mA
-0.3
5.5
V
Input Threshold
Turn On
CTRL increasing
3.5
V
Turn Off
CTRL decreasing
1.5
V
Hysteresis
0.4
2.0
V
Voltage
I
CTRL
=10A MAX
1.1
V
Input Capacitance
50
pF
s Current Limit Increase Function
Input Voltage Range
I
CTRL
=2mA
-0.3
5.5
V
Input Threshold
Turn On
CLI increasing
3.5
V
Turn Off
CLI decreasing
1.5
V
Hysteresis
0.4
2.0
V
Voltage
I
CLI
=10A max
1.1
V
Input Capacitance
50
pF
s Output Stage
I
OUT
5
mA
s Flag Function
Output Low
V
CTRL
=5.5V; I
FLAG
=1.5mA
0.9
V
Leakage Current
V
CTRL
=-0.3V
10
A
Output Capacitance
50
pF
Turn On (V
SENSE+
V
SENSE-
)
V
CTRL
=5.5V; V
CLI
=-0.3V
210
225
240
mV
V
CTRL
=5.5V; V
CLI
=5.5V
300
350
mV
3
Electrical Characteristics continued
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
CS8312
Package Pin Description
PACKAGE PIN #
PIN SYMBOL
FUNCTION
8L PDIP & SO
1
FLAG
Indicates whether current through the IGBT has reached a pre-
set level.
2
SENSE+
Positive input to current comparator.
3
SENSE
Ground (SENSE-) for current sense resistor.
4
Gnd
Ground connection.
5
OUT
Output voltage to IGBT (MOSFET) gate.
6
CLI
Current limit input increase.
7
CTRL
Control input.
8
V
CC
Supply voltage.
The flag indicates when the voltage across the two sense
pins is approaching a current limit level that has been
determined by the value of the external sense resistor
(R
SENSE
) and the state of the CTRL and CLI pins. If the
voltage across the sense pins (SENSE+, SENSE-) is less
than the flag turn-on voltage, then the FLAG is off. When
the voltage between the sense pins equals the FLAG turn
on voltage, the FLAG will latch on until the CTRL pin
goes low. FLAG is disabled whenever CTRL is low.
Changing the CLI pin from low to high will increase
nominal FLAG turn on voltage by approximately 45%.
Table 1 FLAG Timing Sequence
The CS8312 output (OUT) saturates and supplies voltage
to the IGBT (or MOSFET) gate once the CTRL switches
from low to high. As current through the IGBT (MOSFET)
increases and the voltage across the sense resistor passes
the flag turn on voltage, the FLAG will turn on. If the cur-
rent through the sense resistor continues to rise and the
sense resistor voltage reaches the regulation sense volt-
age, then the gate voltage will fall to a level that regulates
the driver and maintains the regulation sense voltage at
the sense resistor.
Changing the CLI pin from a logic low to a logic high
increases the FLAG turn on voltage by approximately
45% and the regulation sense voltage by approximately
39% respectively.
Current Limit Function
Output Stage
State
CONTROL
SENSE+
FLAG
0
Low
X
OFF
1
High
Below Threshold
OFF
2
High
Above Threshold
ON
3
High
X
ON
0
Low
X
OFF
Flag Function (see Application Diagram)
Circuit Description
s Flag Function: continued
Turn Off Delay
CTRL decreasing
10
us
Turn On Delay
10
us
Disable Time
100
450
us
s Sense Function
Input Voltage Range
-0.3
2.5
V
Sense Regulation Voltage
V
CTRL
=5.5V; V
CLI
=-0.3V
270
295
320
mV
V
CTRL
=5.5V; V
CLI
=5.5V
380
410
440
mV
Input Leakage Current
V
CTRL
=5.5V
5
A
Propagation Delay
V
CTRL
=5.5V
20
us
4
Application and Test Diagram
CS8312
FLAG
SENSE+
SENSE
Gnd
V
CC
CTRL
CLI
OUT
CS8312
V
CC
V
CC
V
BA
T
0.1
mF
LOAD
R
SENSE
R
Microprocessor
Part Number
Description
CS8312YN8
8L PDIP
CS8312YD8
8L SO Narrow
CS8312YDR8
8L SO Narrow (tape & reel)
5
CS8312
Thermal Data
8L SO
8L PDIP
R
QJC
typ
45
52
C/W
R
QJA
typ
165
100
C/W
Package Specification
PACKAGE DIMENSIONS IN mm (INCHES)
Ordering Information
PACKAGE THERMAL DATA
Rev. 4/7/97
D
Lead Count
Metric
English
Max
Min
Max
Min
8 Lead SO Narrow
5.00
4.80
.197
.189
8 Lead PDIP
10.16
9.02
.400
.355
1999 Cherry Semiconductor Corporation
Cherry Semiconductor Corporation reserves the
right to make changes to the specifications without
notice. Please contact Cherry Semiconductor
Corporation for the latest available information.
Surface Mount Narrow Body (D); 150 mil wide
Plastic DIP (N); 300 mil wide
0.39 (.015)
MIN.
2.54 (.100) BSC
1.77 (.070)
1.14 (.045)
D
Some 8 and 16 lead
packages may have
1/2 lead at the end
of the package.
All specs are the same.
.203 (.008)
.356 (.014)
REF: JEDEC MS-001
3.68 (.145)
2.92 (.115)
8.26 (.325)
7.62 (.300)
7.11 (.280)
6.10 (.240)
.356 (.014)
.558 (.022)
1.27 (.050) BSC
0.51 (.020)
0.33 (.013)
6.20 (.244)
5.80 (.228)
4.00 (.157)
3.80 (.150)
1.57 (.062)
1.37 (.054)
D
0.25 (0.10)
0.10 (.004)
1.75 (.069) MAX
1.27 (.050)
0.40 (.016)
REF: JEDEC MS-012
0.25 (.010)
0.19 (.008)
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