BCDSEMI AZ4052MTR-G1

Preliminary Datasheet
Dual 4-channel Analog Multiplexer/Demultiplexer
General Description
Features
The AZ4052 is high-speed si-gate CMOS device. The
AZ4052 is dual 4-channel analog multiplexers or
demultiplexers with common select logic. Each
multiplexer has four independent inputs/outputs (pins
nY0 to nY3) and a common input/output (pin nZ).
The common channel select logics include two digital
select inputs (pins S0 and S1) and an active LOW
•
•
___
Wide Operation Voltage: ±5.0V or 10V
Low On-resistance:
- 55Ω (Typ.) at VCC-VEE=5V
- 40Ω ( Typ.) at VCC-VEE=10V
Ultra Low THD+N:
0.003% @ 10V, 0.008% @ 5.0V
Ultra Low Crosstalk: -120dB
Ultra Low Noise: 6.0μVRMS
Operating Temperature: -40ºC to 85ºC
•
•
•
•
___
enable input (pin E ). When pin E =LOW, one of the
four switches is selected (Low-impedance On-state)
AZ4052
___
with pins S0 and S1. When pin E =HIGH, all
switches are in the high-impedance Off-state,
independent of pins S0 and S1. VCC and GND are the
supply voltage pins for the digital control inputs (pins
Applications
•
•
___
S0, S1 and E ). The VCC to GND ranges are 3.0V to
10V. The analog inputs/outputs (pins nY0 to nY3 and
nZ) can swing between VCC as a positive limit and
VEE as a negative limit. VCC-VEE may not exceed 10V.
For operation as a digital multiplexer/demultiplexer,
VEE is connected to GND (Typically Ground).
LCD TV/PDP TV/CRT TV
4:1 Multi-channel Signal Selecting
Function Table
Control Input
___
The AZ4052 is available in standard packages of
SOIC-16 and DIP-16.
E
L
L
L
L
H
S1
L
L
H
H
X
SOIC-16
On Channel
S0
L
H
L
H
X
nY0
nY1
nY2
nY3
nZ
nZ
nZ
nZ
None
DIP-16
Figure 1. Package Types of AZ4052
Oct. 2011
Rev. 1.1
BCD Semiconductor Manufacturing Limited
1
Preliminary Datasheet
Dual 4-channel Analog Multiplexer/Demultiplexer
AZ4052
Pin Configuration
M Package
P Package
(SOIC-16)
(DIP-16)
2Y0
1
16
VCC
2Y2
2
15
1Y2
2Z
3
14
1Y1
2Y3
4
13
1Z
2Y1
5
12
1Y0
E
6
11
1Y3
VEE
7
10
S0
GND
8
9
S1
Figure 2. Pin Configuration of AZ4052 (Top View)
Pin Descriptions
Pin Number
Pin Name
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
2Y0
2Y2
2Z
2Y3
2Y1
Oct. 2011
E
VEE
GND
S1
S0
1Y3
1Y0
1Z
1Y1
1Y2
VCC
Function
2CH signal input or output terminal 0
2CH signal input or output terminal 2
2CH common signal input or output terminal
2CH signal input or output terminal 3
2CH signal input or output terminal 1
Enable input (Active LOW)
Negative supply voltage
Ground (0V)
Select logic input terminal 1
Select logic input terminal 0
1CH signal input or output terminal 3
1CH signal input or output terminal 0
1CH common signal input or output terminal
1CH signal input or output terminal 1
1CH signal input or output terminal 2
Positive supply voltage
Rev. 1. 1
BCD Semiconductor Manufacturing Limited
2
Preliminary Datasheet
Dual 4-channel Analog Multiplexer/Demultiplexer
AZ4052
Functional Block Diagram
Figure 3. Functional Block Diagram of AZ4052
Schematic Diagram (One Switch)
Figure 4. Schematic Diagram of AZ4052
Oct. 2011
Rev. 1. 1
BCD Semiconductor Manufacturing Limited
3
Preliminary Datasheet
Dual 4-channel Analog Multiplexer/Demultiplexer
AZ4052
Ordering Information
AZ4052
Circuit Type
G1: Green
Package
M: SOIC-16
P: DIP-16
TR: Tape & Reel
Blank: Tube
Package
Temperature
Range
SOIC-16
-40 to 85°C
DIP-16
-
-40 to 85°C
Part Number
Marking ID
Packing
Type
AZ4052M-G1
AZ4052M-G1
Tube
AZ4052MTR-G1
AZ4052M-G1
Tape & Reel
AZ4052P-G1
AZ4052P-G1
Tube
BCD Semiconductor's Pb-free products, as designated with "G1" suffix in the part number, are RoHS compliant
and Green.
Oct. 2011
Rev. 1. 1
BCD Semiconductor Manufacturing Limited
4
Preliminary Datasheet
Dual 4-channel Analog Multiplexer/Demultiplexer
AZ4052
Absolute Maximum Ratings (Note 1, 2)
Parameter
Symbol
Value
Unit
-0.5 to 11.0
V
20
mA
20
mA
25
mA
20
mA
50
mA
500
mW
TSTG
-65 to 150
ºC
TJ
150
ºC
PS
100
mW
ESD (Machine Model)
200
V
ESD (Human Body Model)
2000
V
Power Supply Voltage
VCC
Input Diode Current
IIK
Switch Diode Current
ISK
Switch Current
IS
VEE Current
VCC Current
GND Current
IEE
ICC
IGND
Power Dissipation
Storage Temperature Range
Operating
Junction
Temperature Range
Power Dissipation Per Switch
PD
Condition
VI<-0.5V,
VI>VCC+0.5V
VS<-0.5V,
VS>VCC+0.5V
-0.5V<VS<VCC+0.5V
TA=-40ºC to 85ºC
(Note 3)
Note 1: Stresses greater than those listed under “Absolute Maximum Ratings” may cause permanent damage to
the device. These are stress ratings only and functional operation of the device at these or any other conditions
beyond those indicated under “Recommended Operating Conditions” is not implied. Exposure to “Absolute
Maximum Ratings” for extended periods may affect device reliability.
Note 2: To avoid drawing VCC current out of pins nZ, when switch current flows in pins nYn, the voltage drop
across the bidirectional switch must not exceed 0.4V. If the switch current flows into pins nZ, no VCC current
will flow out of pins nYn. In this case there is no limit for the voltage drop across the switch, but the voltages at
pins nYn and nZ may not exceed VCC or VEE.
Note 3: Above 70ºC derate linearly with 12mW/K (DIP-16 package).
Above 70ºC derate linearly with 8mW/K (SOIC-16 package)
Oct. 2011
Rev. 1. 1
BCD Semiconductor Manufacturing Limited
5
Preliminary Datasheet
Dual 4-channel Analog Multiplexer/Demultiplexer
AZ4052
Recommended Operating Conditions
Parameter
Symbol
Condition
Min
Typ
Max
VCC-GND
3.0
10
VCC-VEE
3.0
10
Unit
V
Supply Voltage
VIN
Logic Input Voltage
Switch Signal Input/
Output Voltage
Operating Ambient
Temperature Range
VI
VEE
VCC
V
VIS/VOS
VEE
VCC
V
TA
-40
85
ºC
Input Rise and Fall
Time
t r, t f
VCC=5.0V
6.0
400
VCC=10V
6.0
250
ns
Electrical Characteristics
DC Characteristics
VIS is the input voltage at pins nYn or nZ, whichever is assigned as an input; VOS is the output voltage at pins nZ
or nYn, whichever is assigned as an output, voltages are referenced to GND (Ground=0V).
Parameter
Symbol
High-level
Input Voltage
VIH
Low-level
Input Voltage
VIL
Input Leakage
Current
ILI
Analog Switch
Off-state
Current
Analog Switch
On-state
Current
Quiescent
Supply
Current
Oct. 2011
IS (Off)
IS (On)
ICC
Other
Conditions
VCC(V)
VI=VCC or GND
VEE(V)
Min
5.0
2.8
10
6.0
Typ
Max
Unit
V
5.0
1.5
10
3.0
V
5.0
0
±1.0
μA
10
0
±1.0
μA
±1.0
μA
VI=VIH or VIL,
︱VS︱=VCC-VEE
(Figure 5)
5.0
Per Channel
10
0
±1.0
μA
All Channels
10
0
±2.0
μA
10
0
±2.0
μA
5.0
0
50
160
μA
10
0
100
320
μA
VI=VIH or VIL,
︱VS︱=VCC-VEE
(Figure 6)
VI=VCC or GND,
VIS=VEE or VCC,
VOS=VCC or VEE
Rev. 1. 1
BCD Semiconductor Manufacturing Limited
6
Preliminary Datasheet
Dual 4-channel Analog Multiplexer/Demultiplexer
AZ4052
Electrical Characteristics (Continued)
Resistance RON
VIS is the input voltage at pins nYn or nZ, which is assigned as an input ((note 4) see figure 7)
Conditions
Parameter
Symbol
Other
On-resistance
(Peak)
RON (Peak)
VIS=VCC to VEE,
VI =VIH or VIL
VIS=VEE,
VI =VIH or VIL
On-resistance
(Rail)
Max
Unit
1000
73
180
Ω
0
1000
47
120
Ω
5.0
0
1000
55
130
Ω
10
0
1000
40
100
Ω
5.0
0
1000
61
150
Ω
10
0
1000
45
110
Ω
5.0
0
5
Ω
10
0
6
Ω
VEE
(V)
IS
(μA)
5.0
0
10
Min
RON (Rail)
VIS=VCC,
VI=VIH or VIL
Maximum
On-resistance
Difference
Between Any Two
Channels
Typ
VCC
(V)
RON
VIS=VCC to VEE,
VI=VIH or VIL
Note 4: When supply voltages (VCC-VEE) near 2.0V the analog switch On-resistance becomes extremely
non-linear. When using a supply of 2V, it is recommended to use these devices only for transmitting digital
signals.
Oct. 2011
Rev. 1. 1
BCD Semiconductor Manufacturing Limited
7
Preliminary Datasheet
Dual 4-channel Analog Multiplexer/Demultiplexer
AZ4052
Electrical Characteristics (Continued)
AC Characteristics
GND=0V, tr=tf=6ns, CL=50pF
Parameter
Symbol
Propagation
Delay
VIS to VOS
tPHL/tPLH
Turn-on
Time
tPZH/tPZL
___
E , Sn to VOS
Turn-off
Time
tPHZ/tPLZ
___
E , Sn to VOS
Conditions
VCC
(V)
Other
Min
VEE
(V)
Typ
Max
Unit
RL=∞
(Figure 24)
5.0
0
15
25
ns
5.0
-5.0
12
25
ns
RL=1kΩ
(Figure 25 and
26)
RL=1kΩ
(Figure 25 and
26)
5.0
0
38
81
ns
5.0
-5.0
26
81
ns
5.0
0
27
63
ns
5.0
-5.0
22
48
ns
Recommended conditions and typical values, GND=0V, TA=25ºC, CL =50pF. VIS is the input voltage at pins nYn
or nZ, whichever is assigned as an input. VOS is the output voltage at pins nYn or nZ, whichever is assigned as an
output.
Conditions
Parameter
Symbol
Sine-wave
Distortion
dSIN
Switch OFF
Signal
Feed-through
Crosstalk
Between Two
Channels
Crosstalk
Between Two
Switches
/Multiplexers
Crosstalk
Voltage
Between
Control and
Any Switch
(Peak-to-peak
Value)
αOFF
(Feedthrough)
Frequency
Response
(-3dB)
Output Noise
Voltage
Oct. 2011
αCT(S)
Min
Typ
Max
Unit
VIS(p-p)
(V)
VCC
(V)
VEE
(V)
f =1kHz,
RL=10kΩ
(Figure 8)
0.5
5.0
0
0.008
%
1.5
10
0
0.003
%
f=10kHz,
RL=10kΩ
(Figure 8)
0.5
5.0
0
0.008
%
1.5
10
0
0.003
%
RL=10kΩ, f=1MHz
(Figure 9),
VIS=1VRMS
RL=10kΩ,
f=1kHz (Figure 10),
VIS=1VRMS
5.0
0
-50
dB
5.0
-5.0
-50
dB
5.0
0
-120
dB
5.0
-5.0
-120
dB
RL =10kΩ,
f=1kHz (Figure 10),
VIS=1VRMS
5.0
0
-60
dB
5.0
-5.0
-60
dB
5.0
0
110
mV
RL=10kΩ
(Figure 8)
5.0
0
70
MHz
5.0
-5.0
70
MHz
A-weighted
5.0
0
6.0
μVRMS
Other
RL =10kΩ,
___
VCT(P-P)
fMAX
VNOISE
f=1MHz, E or Sn,
Square-wave
Between VCC and
GND,
tr= tf=6ns
(Figure 11)
Rev. 1. 1
BCD Semiconductor Manufacturing Limited
8
Preliminary Datasheet
Dual 4-channel Analog Multiplexer/Demultiplexer
AZ4052
Typical Test Circuit
LOW
(From Select Input)
HIGH
(From Select Input)
nYn
nZ
A
nYn
A
VI=VCC or VEE
nZ
A
VO=VEE or VCC
VIS=VEE or VCC
VOS (Open
Circuit)
VEE
VEE
Figure 5. Test Circuit for Measuring OFF-state Current
HIGH
(From Select Input)
Figure 6. Test Circuit for Measuring ON-state Current
V
nYn
VIS=0 to VCC-VEE
nZ
IIS
VEE
Figure 8. Test Circuit for Measuring Sine-wave
Distortion and Minimum Frequency Response
Figure 7. Test Circuit for Measuring RON
Oct. 2011
Rev. 1. 1
BCD Semiconductor Manufacturing Limited
9
Preliminary Datasheet
Dual 4-channel Analog Multiplexer/Demultiplexer
AZ4052
Typical Test Circuit (Continued)
CIN
RL nYn/nZ
nZ/nYn
VIS
Vos
RL
Channel
ON
CIN
nYn/nZ
Channel
OFF
RL
CL
GND
(a) Channel ON Condition
nZ/nYn
VIS
CL
Vos
dB
GND
CIN
nYn/nZ
nZ/nYn
VIS
Vos
RL
RL
Channel
OFF
dB
CL
GND
(b) Channel OFF Condition
Figure 9. Test Circuit for Measuring Switch
Off Signal Feed-through
Figure 10. Test Circuits for Measuring Crosstalk
Between Any Two Switches/Multiplexers
The crosstalk is defined as follows
(oscilloscope output):
V(p-p)
VCC
VCC
2RL
nYn/nZ
VCC
VCC
Sn or E
2RL
2RL
RL
nZ/nYn
DUT
VI
DUT
Pulse
Generator
2RL
CL
Oscilloscope
RT
GND
VO
CL
GND
VEE
VEE
Figure 11. Test Circuit for Measuring Crosstalk
Performance
Oct. 2011
Open
VIS
Rev. 1. 1
Figure 12. Test Circuit for Measuring AC
Between Control and Any Switch
BCD Semiconductor Manufacturing Limited
10
Preliminary Datasheet
Dual 4-channel Analog Multiplexer/Demultiplexer
AZ4052
Typical Performance Characteristics
80
70
VCC=5V,VEE=0V
75
65
VCC=10V
60
VEE=0V
70
RDSON (Ω)
RDSON (Ω)
55
65
60
55
50
45
40
35
50
30
45
25
40
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
20
5.0
0
2
4
Signal Output (V)
Figure 13. RDSON vs. Signal Output
10
8
10
Figure 14. RDSON vs. Signal Output
10
VCC=5V,VEE=0V
VCC=10V,VEE=0V
RL=10kΩ
RL=10kΩ
f=1kHz
f=1kHz
1
THD+N (%)
THD+N (%)
6
Signal Output (V)
1
0.1
0.1
0.01
0.01
0.1
1E-3
1
0.1
Figure 15. THD+N vs. Output Voltage Amplitude
Oct. 2011
1
Output Voltage Amplitude
Output Voltage Amplitude
Figure 16. THD+N vs. Output Voltage Amplitude
Rev. 1. 1
BCD Semiconductor Manufacturing Limited
11
Preliminary Datasheet
Dual 4-channel Analog Multiplexer/Demultiplexer
AZ4052
Typical Performance Characteristics (Continued)
1
20
10
Signal Output Voltage (dBV)
0
Gain (dB )
-1
-2
-3
-4
0
-10
-30
-40
-50
-60
-70
-80
-90
-100
RL=10KΩ
-110
10k
100k
1M
10M
RL=10kΩ
f=1kHz
-20
VCC=2.5V, VEE=-2.5V
-5
1k
VCC=5V, VEE=0V
-120
-120 -110 -100 -90 -80 -70 -60 -50 -40 -30 -20 -10
100M
0
10
20
Signal Input Voltage (dBV)
Frequency (Hz)
Figure 17. Frequency Response
Figure 18. Linear Range
20
0
-10
VCC=10V, VEE=0V
VCC=5V, VEE=0V
RL=10kΩ
f=1kHz
VIS
1V/div
-20
-30
-40
-50
-60
-70
-80
VOS
1V/div
Signal Output Voltage (dBV)
10
-90
-100
-110
-120
-120 -110 -100 -90 -80 -70 -60 -50 -40 -30 -20 -10
0
10
20
10ns/div
Signal Input Voltage (dBV)
Figure 19. Linear Range
Oct. 2011
Figure 20. Propagation Delay
Rev. 1. 1
BCD Semiconductor Manufacturing Limited
12
Preliminary Datasheet
Dual 4-channel Analog Multiplexer/Demultiplexer
AZ4052
Typical Performance Characteristics (Continued)
0
VOS
1V/div
VCC=5V, VEE=0V
-10
VCC=5V, VEE=0V
-20
RL=10kΩ
2Y0 to 1Y0
1Y0 to 2Y0
-30
VIS
1V/div
Crosstalk (dB)
-40
-50
-60
-70
-80
-90
-100
-110
-120
-130
100
1k
10k
100k
Frequency (Hz)
10ns/div
Figure 22. Crosstalk vs. Frequency
Figure 21. Propagation Delay
0
-10
VCC=10V,VEE=0V
-20
RL=10kΩ
-30
2Y0 to 1Y0
1Y0 to 2Y0
Crosstalk (dB)
-40
-50
VIS
Output
VI
50%
GND
-60
-70
tPLH
-80
tPHL
VOH
-90
VOS
Output
-100
-110
-120
50%
VOL
-130
-140
100
1k
10k
100k
Frequency (Hz)
Figure 23. Crosstalk vs. Frequency
Oct. 2011
Figure 24. Waveforms Showing the Input (VIS)
to Output (VOS) Propagation Delays
Rev. 1. 1
BCD Semiconductor Manufacturing Limited
13
Preliminary Datasheet
Dual 4-channel Analog Multiplexer/Demultiplexer
AZ4052
Typical Performance Characteristics (Continued)
Figure 25. Waveforms Showing the Turn-on and Turn-off Times
(VM = 50 %, VI = GND to VCC)
Figure 26. Input Pulse Definitions
Oct. 2011
Amplitude
VM
VCC
50%
tr and tf
Fmax Pulse
Width
< 2ns
Rev. 1. 1
Other
6ns
BCD Semiconductor Manufacturing Limited
14
Preliminary Datasheet
Dual 4-channel Analog Multiplexer/Demultiplexer
AZ4052
Typical Application
Figure 27. Typical Application of AZ4052
Oct. 2011
Rev. 1. 1
BCD Semiconductor Manufacturing Limited
15
Preliminary Datasheet
Dual 4-channel Analog Multiplexer/Demultiplexer
AZ4052
Mechanical Dimensions
SOIC-16
1.350(0.053)
1.750(0.069)
7°
0.330(0.013)
0.510(0.020)
Unit: mm(inch)
1.250(0.049)
1.650(0.065)
7°
B
A
20:1
0.250(0.010)
0.400(0.016)
9.800(0.386)
10.200(0.402)
0°
8°
R0.200(0.008)
R0.200(0.008)
0.050(0.002)
0.250(0.010)
0.170(0.007)
0.250(0.010)
5.800(0.228)
6.240(0.246)
3.800(0.150)
4.040(0.159)
9.5
°
8°
A
0.400(0.016)×45°
0.200(0.008)
Sφ1.000(0.039)
Depth 0.200(0.008)
8°
8°
C-C
50:1
B
20:1
C
3°
7°
0.200(0.008)
0.250(0.010)
1.000(0.039)
1.270(0.050)
BSC
1.270(0.050)
C
Note: Eject hole, oriented hole and mold mark is optional.
Oct. 2011
Rev. 1. 1
BCD Semiconductor Manufacturing Limited
16
Preliminary Datasheet
Dual 4-channel Analog Multiplexer/Demultiplexer
AZ4052
Mechanical Dimensions (Continued)
DIP-16
Oct. 2011
Rev. 1. 1
Unit: mm(inch)
BCD Semiconductor Manufacturing Limited
17
BCD Semiconductor Manufacturing Limited
http://www.bcdsemi.com
IMPORTANT NOTICE
IMPORTANT
NOTICE
BCD Semiconductor
BCD
Semiconductor Manufacturing
Manufacturing Limited
Limited reserves
reserves the
the right
right to
to make
make changes
changes without
without further
further notice
notice to
to any
any products
products or
or specifispecifications herein.
cations
herein. BCD
BCD Semiconductor
Semiconductor Manufacturing
Manufacturing Limited
Limited does
does not
not assume
assume any
any responsibility
responsibility for
for use
use of
of any
any its
its products
products for
for any
any
particular purpose,
particular
purpose, nor
nor does
does BCD
BCD Semiconductor
Semiconductor Manufacturing
Manufacturing Limited
Limited assume
assume any
any liability
liability arising
arising out
out of
of the
the application
application or
or use
use
of any
of
any its
its products
products or
or circuits.
circuits. BCD
BCD Semiconductor
Semiconductor Manufacturing
Manufacturing Limited
Limited does
does not
not convey
convey any
any license
license under
under its
its patent
patent rights
rights or
or
other rights
other
rights nor
nor the
the rights
rights of
of others.
others.
MAIN SITE
SITE
MAIN
- Headquarters
BCD
Semiconductor Manufacturing Limited
BCD
Semiconductor
Manufacturing Limited
- Wafer
Fab
No.
1600, Zi
Xing Road,
Shanghai ZiZhu
Science-basedLimited
Industrial Park, 200241, China
Shanghai
SIM-BCD
Semiconductor
Manufacturing
Tel:
Fax: +86-21-24162277
800,+86-21-24162266,
Yi Shan Road, Shanghai
200233, China
Tel: +86-21-6485 1491, Fax: +86-21-5450 0008
REGIONAL SALES OFFICE
Shenzhen OfficeSALES OFFICE
REGIONAL
- Wafer
FabSemiconductor Manufacturing Limited
BCD
Shanghai
SIM-BCD
Semiconductor Manufacturing Co., Ltd.
- IC Design
Group
800 Yi
Shan Road,
Shanghai
200233,
China Corporation
Advanced
Analog
Circuits
(Shanghai)
Tel: +86-21-6485
1491,YiFax:
0008200233, China
8F, Zone B, 900,
Shan+86-21-5450
Road, Shanghai
Tel: +86-21-6495 9539, Fax: +86-21-6485 9673
Taiwan Office
Shanghai
Semiconductor Manufacturing Co., Ltd., Shenzhen Office
BCD Taiwan
Semiconductor
Shenzhen SIM-BCD
Office
Office (Taiwan) Company Limited
Unit
A Room
1203, Skyworth
Bldg., Gaoxin
Ave.1.S., Nanshan
Shenzhen,
4F, 298-1,
Guang Road,(Taiwan)
Nei-Hu District,
Taipei,
Shanghai
SIM-BCD
Semiconductor
Manufacturing
Co., Ltd.District,
Shenzhen
Office
BCDRui
Semiconductor
Company
Limited
China
Taiwan
Advanced Analog Circuits (Shanghai) Corporation Shenzhen Office
4F, 298-1, Rui Guang Road, Nei-Hu District, Taipei,
Tel:
+86-755-8826
Tel: +886-2-2656
2808
Room
E, 5F, Noble 7951
Center, No.1006, 3rd Fuzhong Road, Futian District, Shenzhen 518026, China
Taiwan
Fax:
+86-755-88267951
7865
Fax: +886-2-2656
28062808
Tel: +86-755-8826
Tel: +886-2-2656
Fax: +86-755-8826 7865
Fax: +886-2-2656 2806
USA Office
BCD Office
Semiconductor Corp.
USA
30920Semiconductor
Huntwood Ave.Corporation
Hayward,
BCD
CA 94544,
USA Ave. Hayward,
30920
Huntwood
Tel :94544,
+1-510-324-2988
CA
U.S.A
Fax:: +1-510-324-2988
+1-510-324-2788
Tel
Fax: +1-510-324-2788