CHERRY CS8312

CS8312
CS8312
IGBT Ignition Predriver
with Dynamic Current Regulation
Features
Description
The CS8312 is a bipolar microprocessor interface IC designed to
drive an IGBT (or logic level
MOSFETs) powering large inductive loads in harsh operating environments. The ICÕs dynamic current limit function lets the microprocessor 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 diagnostic FLAG output signal. The
FLAG output signals the microprocessor when the current level
approaches current limit on the
IGBT. The CTRL input enables the
FLAG function.
■ µP Compatible Inputs
■ Adjustable Current Limit
Thresholds
■ External Sense Resistor
■ Flag Signal to Indicate
Output Status
Absolute Maximum Ratings
Supply Voltage.................................................................................-0.3V to +12V
Digital Input Currents....................................................................................2mA
Internal Power Dissipation (TA = 25¡C) .................................................700mW
Junction Temperature Range.....................................................-40¡C to +150¡C
Storage Temperature Range ......................................................-55¡C to +165¡C
Lead Temperature Soldering
Wave Solder(through hole styles only).............10 sec. max, 260¡C peak
Reflow (SMD styles only).............60 sec. max above 183¡C, 230¡C peak
Electrostatic Discharge (Human Body Model) ............................................2kV
Block Diagram
Package Options
8L PDIP & SO Narrow
VCC
FLAG 1
CTRL
Control
Logic
Gate
Driver
OUT
VCC
SENSE+
CTRL
SENSEÐ
CLI
Gnd
OUT
VT
SENSE+
FLAG
Latch
VREF
VT
Gnd
CLI
SENSEÐ
Cherry Semiconductor Corporation
2000 South County Trail, East Greenwich, RI 02818
Tel: (401)885-3600 Fax: (401)885-5786
Email: [email protected]
Web Site: www.cherry-semi.com
Rev. 4/7/97
1
A
¨
Company
CS8312
Electrical Characteristics 7V ² VCC ² 10V; -40¡C ² TA ² +125¡C; unless otherwise specified
PARAMETER
■ General
Power Supply
including Ripple Voltage
Supply Ripple Frequency
Differential Ground Voltage
TEST CONDITIONS
DC SENSE- to Gnd
AC SENSE- to Gnd
Differential Ground Frequency
Quiescent Current, IQ
Turn On
Turn Off
Supply Voltage Rejection
Differential Ground
Rejection Ratio
Differential Ground Current
Ratio
Unity Gain Bandwidth
Clamp Voltage
Output Off Voltage
Turn On Delay
Turn Off Delay
VCTRL=5.5V
VCTRL=-0.3V
VCTRL=5.5V
VCTRL=5.5V
MIN
TYP
MAX
7
10
V
10
-0.1
-0.2
10
60
1.0
0.6
60
kHz
V
V
kHz
15
5
mA
mA
dB
dB
3
mA
5.5
0.5
1.2
30
30
kHz
V
V
V
us
us
5.5
V
3.5
2.0
1.1
50
V
V
V
V
pF
5.5
V
3.5
2.0
1.1
50
V
V
V
V
pF
5
mA
0.9
10
50
240
350
V
µA
pF
mV
mV
30
30
VCTRL= -0.3V
(VSENSE--VGnd)DC=1V
(VSENSE--VGnd)AC=0.6V
VCTRL=5.5V
VCTRL=5.5V; IOUT=1mA
VCTRL=-0.3V; IOUT=10µA
VCTRL=-0.3V; IOUT=200µA
CTRL increasing
CTRL decreasing
UNIT
400
■ Control Function
Input Voltage Range
Input Threshold
Turn On
Turn Off
Hysteresis
Voltage
Input Capacitance
ICTRL=2mA
-0.3
CTRL increasing
CTRL decreasing
1.5
0.4
ICTRL=10µA MAX
■ Current Limit Increase Function
Input Voltage Range
ICTRL=2mA
Input Threshold
Turn On
Turn Off
Hysteresis
Voltage
Input Capacitance
-0.3
CLI increasing
CLI decreasing
1.5
0.4
ICLI=10µA max
■ Output Stage
IOUT
■ Flag Function
Output Low
Leakage Current
Output Capacitance
Turn On (VSENSE+ Ð VSENSE-)
VCTRL=5.5V; IFLAG=1.5mA
VCTRL=-0.3V
VCTRL=5.5V; VCLI=-0.3V
VCTRL=5.5V; VCLI=5.5V
2
210
300
225
PARAMETER
TEST CONDITIONS
■ Flag Function: continued
Turn Off Delay
Turn On Delay
Disable Time
■ Sense Function
Input Voltage Range
Sense Regulation Voltage
Input Leakage Current
Propagation Delay
MIN
TYP
MAX
CTRL decreasing
100
-0.3
270
380
VCTRL=5.5V; VCLI=-0.3V
VCTRL=5.5V; VCLI=5.5V
VCTRL=5.5V
VCTRL=5.5V
295
410
UNIT
10
10
450
us
us
us
2.5
320
440
5
20
V
mV
mV
µA
us
Package Pin Description
PACKAGE PIN #
PIN SYMBOL
FUNCTION
8L PDIP & SO
1
FLAG
Indicates whether current through the IGBT has reached a preset level.
2
SENSE+
Positive input to current comparator.
3
SENSEÐ
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
VCC
Supply voltage.
Circuit Description
Flag Function (see Application Diagram)
Output Stage
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
(RSENSE) 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%.
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 current through the sense resistor continues to rise and the
sense resistor voltage reaches the regulation sense voltage, then the gate voltage will fall to a level that regulates
the driver and maintains the regulation sense voltage at
the sense resistor.
Current Limit Function
Table 1 FLAG Timing Sequence
State
0
1
2
3
0
CONTROL
Low
High
High
High
Low
SENSE+
X
Below Threshold
Above Threshold
X
X
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.
FLAG
OFF
OFF
ON
ON
OFF
3
CS8312
Electrical Characteristics continued
CS8312
Application and Test Diagram
VCC
VBA
T
LOAD
0.1mF
VCC
VCC
OUT
CS8312
R
FLAG
Microprocessor
CTRL
SENSE+
CLI
RSENSE
SENSEÐ
Gnd
4
CS8312
Package Specification
PACKAGE THERMAL DATA
PACKAGE DIMENSIONS IN mm (INCHES)
D
Lead Count
8 Lead SO Narrow
8 Lead PDIP
Metric
Max
Min
5.00
4.80
10.16
9.02
Thermal Data
English
Max Min
.197 .189
.400 .355
RQJC
RQJA
8L SO
typ
typ
45
165
8L PDIP
52
100
ûC/W
ûC/W
Surface Mount Narrow Body (D); 150 mil wide
4.00 (.157)
3.80 (.150)
6.20 (.244)
5.80 (.228)
0.51 (.020)
0.33 (.013)
1.27 (.050) BSC
1.75 (.069) MAX
1.57 (.062)
1.37 (.054)
1.27 (.050)
0.40 (.016)
0.25 (.010)
0.19 (.008)
D
0.25 (0.10)
0.10 (.004)
REF: JEDEC MS-012
Plastic DIP (N); 300 mil wide
7.11 (.280)
6.10 (.240)
8.26 (.325)
7.62 (.300)
1.77 (.070)
1.14 (.045)
2.54 (.100) BSC
3.68 (.145)
2.92 (.115)
.356 (.014)
.203 (.008)
0.39 (.015)
MIN.
.558 (.022)
.356 (.014)
REF: JEDEC MS-001
D
Some 8 and 16 lead
packages may have
1/2 lead at the end
of the package.
All specs are the same.
Ordering Information
Part Number
CS8312YN8
CS8312YD8
CS8312YDR8
Rev. 4/7/97
Description
8L PDIP
8L SO Narrow
8L SO Narrow (tape & reel)
Cherry Semiconductor Corporation reserves the
right to make changes to the specifications without
notice. Please contact Cherry Semiconductor
Corporation for the latest available information.
5
© 1999 Cherry Semiconductor Corporation