NSC LMC2626IM

November 1995
LMC2626
CMOS LDOR/Buffer Chip for Row
Inversion Flat Panel Display Systems
General Description
Features
The LMC2626 integrated circuit is specifically developed for
a row inversion TFT FPD system architecture. It is designed
only to be used in conjunction with National’s LM2625
switching regulator chip.
Built on National’s advanced CMOS CS80 process, this chip
generates a high-power, precision square-wave from a digital sync signal. The chip also contains thermal shutdown
circuitry, system shutdown circuitry, and a low drop-out voltage regulator to generate a 4.2 volt supply from an externally applied reference voltage of 1.227V.
Y
Connection Diagram
Pin Description
Y
Y
Y
Y
Y
Y
Y
Y
Used in conjunction with LM2625 chip
High output current buffer
Low buffer on resistance
System shutdown control
LDO voltage regulator
LDOR dropout 0.3V maximum at 150 mA
Thermal shutdown/short circuit protection
External reference required for LDOR
VREF pin converts to a digital pin to shutdown LM2625
8-Pin SO
Pin Ý
Pin Name
Description
1
VREF
1.218V to 1.242V Ext. Reference
from LM2625 (see Note 8)
2
SD
System Shutdown input pin for
LMC2626 and LMC2625
3
SYNC
Digital input square wave from FPD
controller
4
GND
Ground
5
P5V
Precision Regulated a 5V Supply
6
VOUT
Power Buffer Output
7
VIN
FPD System Supply ( a 4.5V to
a 5.5V)
8
VSH
Low Drop-Out Voltage Regulator
Output
TL/H/12541 – 1
Top View
Ordering Information
Package
Temperature Range
b 40§ C to a 85§ C
NSC
Drawing
Transport
Media
8-Pin SO
LMC2626IM
M08A
Rail
Tape and
Reel
C1996 National Semiconductor Corporation
TL/H/12541
RRD-B30M26/Printed in U. S. A.
LMC2626 CMOS LDOR/Buffer Chip for Row Inversion Flat Panel Display Systems
PRELIMINARY
Absolute Maximum Ratings (Note 1)
Operating Ratings (Note 1)
ESD Tolerance 2 kV HBM, 200V MM (Note 4)
VIN Supply Voltage
P5V Supply Voltage (Note 5)
4.8V s P5V s 5.2V
Junction Temperature Range
Ambient Temperature Range
b 25§ C to a 125§ C
b 40§ C to a 85§ C
Sync Input Voltage
P5V
6.3V
Supply Voltage (VIN, P5V)
Continuous Total Power Dissipation (Note 1)
Lead Temperature (less than 10 sec)
260§ C
b 65§ C to a 150§ C
Storage Temperature Range
Junction Temperature
150§ C
4.5V s VIN s 5.5V
DC Electrical Characteristics
Unless otherwise specified, all limits guaranteed for b20§ C s TA s a 85§ C, P5V e 5V and 4.5V s VIN s 5.5V, VREF e 1.227V
SYNC(OPEN), SD(OPEN) k P5V e VIN e 5V
VSH LDO Voltage Regulator (Notes 7, 10, 11)
Symbol
VO(VREF)
Parameter
VREF Voltage Level
in Shutdown
Min
Typ
(Note 9)
4.00
4.76
b 40.0
b 13.3
b5
mA
4.10
4.20
4.30
V
4
126
mV
0.17
0.30
V
Conditions
SD e 0V
IVREF e b1 mA
VIN e 5V
IVREF
DC Current from
VREF Pin
VSH
Output Voltage on
VSH Pin (see Note 2)
4.5V s VIN s 5.5V
20 mA s IL s 150 mA
1.218 s VREF s 1.242
DVSH
Variation of VSH over
Temperature
4.5V s VIN s 5.5V
20 mA s IL s 150 mA
VDO
LDOR Voltage Dropout
(VIN – VSH)
IL e 150 mA
IS(VIN)
VIN Supply Current
230
Max
Units
V
394
500
mA
Load Regulation of LDO
Voltage Regulation
4.5V s VIN s 5.5V
20 mA s IL s 150 mA
0.002
0.015
%/mA
Line Regulation of LDOR
4.5V s VIN s 5.5V
20 mA s IL s 150 mA
0.24
0.95
%/V
TSD
Thermal Shutdown
Threshold
(see Note 8)
IOUT
Output Load Current
(see Note 2)
160
§C
300
mA
Shutdown Control (Note 8)
Symbol
Parameter
Conditions
IIL(SD)
Low Level Input Current
for SD Pin
VIN e 5V
SD e 0V
IIH(SD)
High Level Input Current
for SD Pin
SD e 5V
Is(SD)
VIN Supply Current
in Shutdown Mode
Cin(SYNC)
Input Capacitance
at SYNC Pin (Note 6)
Min
Typ
(Note 9)
Max
Units
b 300
b 217
b 150
mA
310
1000
nA
285
400
mA
180
SYNC e 5V
TA e 27§ C
2
20
pF
DC Electrical Characteristics
Unless otherwise specified, all limits guaranteed for b20§ C s TA s a 85§ C, P5V e 5V and 4.5V s VIN s 5.5V, VREF e 1.227V
SYNC(OPEN), SD(OPEN) k P5V e VIN e 5V (Continued)
Buffer
Symbol
Parameter
Conditions
Min
Typ
(Note 9)
4.997
4.999
VOUT
Peak to Peak Output
Voltage Swing or VOUT
SYNC e 5Vpp
(no load)
VOL
Low Level Output
Voltage
SYNC e 0V
(No Load)
0.2
VOH
High Level Output
Voltage
SYNC e 5V
(No Load)
4.999
DVOUT
Variation of VOUT
Over Temperature
0.2
1
VIH
SYNC, SD
High Level Input
Voltage
3.5
5
VIL
SYNC, SD
Low Level Input
Voltage
IIL(SYNC)
Low Level Input
Current for SYNC
SYNC e 0V
IIH(SYNC)
High Level Input
Current for SYNC
SYNC e 5VDC
IOUT-AVE
VOUT Maximum Average
Load Current from (see Note 2)
SYNC e 5VPP
RON
N-Channel
On Resistance
IL e 150 mA
TA e 27§ C
RON
P-Channel
On Resistance
RON
Matching
Is
Max
Units
V
2
mV
V
3
mV
V
0
1.5
V
5.0
42
1000
nA
170
215
275
mA
100
mA
0.9
1.5
X
IL e 150 mA
TA e 27§ C
0.7
1.2
X
On Resistance
IL e 150 mA
TA e 27§ C
0.18
0.6
X
Supply Current
from P5V
No SYNC
355
950
mA
3
200
AC Electrical Characteristics
Unless otherwise specified, all limits guaranteed for TA e 27§ C, VIN e e P5V e 5V. Other conditions are shown in the test
circuit. Conditions that deviate from those shown in the test circuit are listed in the conditions column.
Symbol
Parameter
Conditions
ts(OUT)
Settling Time for VOUT
To 98% p-p VOUT,
VIN e 5V (see Note 3)
Min
Typ
(Note 9)
Max
Units
5.0
ms
Note 1: Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating ratings indicate conditions the device is intended
to be functional, but device parameter specifications may not be guaranteed under these conditions. For guaranteed specifications and test conditions, see
the Electrical Characteristics.
Note 2: The typical junction-ambient thermal resistance of the molded plastic SO(M) package is 155§ C/W. Therefore the maximum current for the buffer and
voltage regulator are limited to the maximum total power dissipation that the package can allow in order to keep the die comfortably below the maximum
operating junction temperature of 125§ C.
Note 3: The settling time of the Power Buffer is mostly dependent upon the TFT effective series RC load. The measurement of the settling time is taken for the
application when driving an all black display. The number in the datasheet reflects a series RC load (R e 6.8X and C e 0.22 mF).
Note 4: Human Body Model 100 pF and 1.5 kX. Machine Model 0X.
Note 5: The precision of the P5V supply determines the output voltage swing precision of the buffer for very small loads. The operating range of P5V in this
datasheet assumes a g 4% error in VOUT p-p such that the total error of the signal at the output of the buffer never exceeds g 5%.
Note 6: This capacitance is dominated by the ESD protection zeners connected to the SYNC pin.
Note 7: It is important to understand that the load current of the low drop-out voltage regulator must not drop below 2 mA. Otherwise, the internal error
amplifier will not have sufficient drive capability to the large series pass transistor. If load requirements from the FPD system is less than 2 mA, an external preIoad resistor must be connected from VSH to ground in order to satisfy the previously mentioned load requirements.
Note 8: The thermal shutdown mode of the voltage regulator and the system shutdown mode are identical. When either of the two functions are enabled, two
results occur. The pass transistor of the voltage regulator is shut off and The VREF pin of the LMC2626 is pulled up to the VIN supply to shutdown the LM2625
switching regulator.
Note 9: Typical values represent the most likely parametric norm.
Note 10: The typical closed loop voltage gain of the low drop-out voltage regulator is 3.44(10.7 dB).
Note 11: The minimum load current of the voltage regulator is a specific parameter used to guarantee that the regulated output voltage of the LDO regulator
stays within the limits specified in the datasheet for 1.216V k VREF k 1.242V. For applications requiring minimum load current less than 20 mA, regulated
output voltage limits of the voltage regulator and VREF voltage range must be carefully determined by characterizing the change in regulated output voltage at
the minimum load current needed.
4
5
LMC2626 CMOS LDOR/Buffer Chip for Row Inversion Flat Panel Display Systems
Physical Dimensions inches (millimeters)
8-Lead (0.150× Wide) Molded Small Outline Package, JEDEC
Order Number LMC2626IM
NS Package M08A
LIFE SUPPORT POLICY
NATIONAL’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT
DEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT OF NATIONAL
SEMICONDUCTOR CORPORATION. As used herein:
1. Life support devices or systems are devices or
systems which, (a) are intended for surgical implant
into the body, or (b) support or sustain life, and whose
failure to perform, when properly used in accordance
with instructions for use provided in the labeling, can
be reasonably expected to result in a significant injury
to the user.
National Semiconductor
Corporation
1111 West Bardin Road
Arlington, TX 76017
Tel: 1(800) 272-9959
Fax: 1(800) 737-7018
2. A critical component is any component of a life
support device or system whose failure to perform can
be reasonably expected to cause the failure of the life
support device or system, or to affect its safety or
effectiveness.
National Semiconductor
Europe
Fax: a49 (0) 180-530 85 86
Email: europe.support @ nsc.com
Deutsch Tel: a49 (0) 180-530 85 85
English Tel: a49 (0) 180-532 78 32
Fran3ais Tel: a49 (0) 180-532 93 58
Italiano Tel: a49 (0) 180-534 16 80
National Semiconductor
Hong Kong Ltd.
13th Floor, Straight Block,
Ocean Centre, 5 Canton Rd.
Tsimshatsui, Kowloon
Hong Kong
Tel: (852) 2737-1600
Fax: (852) 2736-9960
National Semiconductor
Japan Ltd.
Tel: 81-043-299-2308
Fax: 81-043-299-2408
National does not assume any responsibility for use of any circuitry described, no circuit patent licenses are implied and National reserves the right at any time without notice to change said circuitry and specifications.