Four 8-Bit D/A Converters With Individual
References
D
Direct Bipolar Operation Without an
External Level-Shift Amplifier
D
Microprocessor Compatible
D
TTL/CMOS Compatible
D
Single Supply Operation Possible
D
Simultaneous Update Facility
D
Binary Input Coding
applications
D
Process Control
D
Automatic Test Equipment
D
Automatic Calibration of Large System
Parameters e.g., Gain/Offset
(MSB) DB7
description
The TLC7225 consists of four 8-bit voltage-output digital-to-analog converters (DACs), with output buffer
amplifiers and interface logic with double register-buffering.
Separate on-chip latches are provided for each of the DACs. Data is transferred into one of these data latches
through a common 8-bit TTL/CMOS-compatible (5 V) input port. Control inputs A0 and A1 determine which DAC
is loaded when WR
converters. The double register buffering allows simultaneous update of all four outputs under control of LDAC
All logic inputs are TTL- and CMOS-level compatible and the control logic is speed compatible with most 8-bit
microprocessors. Each DAC includes an output buffer amplifier capable of driving up to 5 mA of output current.
goes low. Only the data held in the DAC registers determines the analog outputs of the
.
The TLC7225 performance is specified for input reference voltages from 2 V to V
– 4 V with dual supplies.
DD
The voltage-mode configuration of the DACs allow the TLC7225 to be operated from a single power-supply rail
at a reference of 10 V.
The TLC7225 is fabricated in a LinBiCMOS process that has been specifically developed to allow high-speed
digital logic circuits and precision analog circuits to be integrated on the same chip. The TLC7225 has a common
8-bit data bus with individual DAC latches. This provides a versatile control architecture for simple interface to
microprocessors. All latch-enable signals are level triggered.
Combining four DACs, four operational amplifiers, and interface logic into a small, 0.3-inch wide, 24-terminal
SOIC allows significant reduction in board space requirements and offers increased reliability in systems using
multiple converters. The pinout optimizes board layout with all of the analog inputs and outputs at one end of
the package and all of the digital inputs at the other.
The TLC7225C is characterized for operation from 0°C to 70°C. The TLC7225I is characterized for operation
from –40°C to 85°C.
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of
Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
LinBiCMOS is a trademark of Texas Instruments Incorporated.
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of Texas Instruments
standard warranty. Production processing does not necessarily include
testing of all parameters.
AGND6Analog ground
A0, A118, 19IDAC select inputs
DGND7Digital ground
DB0 – DB79 – 16IDigital DAC data inputs
LDAC8Load DAC. A high level simultaneously loads all four DAC registers. DAC registers are transparent when LDAC
is low.
OUTA2ODACA output
OUTB1ODACB output
OUTC24ODACC output
OUTD23ODACD output
REFA5IVoltage reference input to DACA
REFB4IVoltage reference input to DACB
REFC21IV oltage reference input to DACC
REFD20IV oltage reference input to DACD
V
DD
V
SS
WR17IWrite input selects DAC transparency or latch mode
22Positive supply voltage
3Negative supply voltage
absolute maximum ratings over operating free-air temperature range (unless otherwise note)
Supply voltage range, V
Supply voltage range, V
Voltage range between AGND and DGND –0.3 V to V
Input voltage range, V
Reference voltage range, V
Output voltage range, V
Continuous total power dissipation at (or below) T
: to AGND or DGND –0.3 V to 17 V. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Lead temperature 1,6 mm (1/16 inch) from case for 10 seconds 260°C. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
†
Stresses beyond 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-rated conditions for extended periods may affect device reliability.
NOTES: 1. Output voltages may be shorted to AGND provided that the power dissipation of the package is not exceeded. Typically sh ort circuit
current to AGND is 50 mA.
2. For operation above TA = 75°C derate linearly at the rate of 2.0 mW/°C.
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
3
TLC7225C, TLC7225I
Operating free-air temperature, T
QUADRUPLE 8-BIT DIGITAL-TO-ANALOG CONVERTERS
SLAS109A – OCTOBER 1996 – REVISED APRIL 1997
recommended operating conditions
Supply voltage, V
Supply voltage, V
High-level input voltage, V
Low-level input voltage, V
Reference voltage, V
Load resistance, R
p
timing requirements (see Figure 1)
t
su(AW)
t
su(DW)
t
h(AW)
t
h(DW)
t
w1
t
w2
DD
SS
IH
IL
ref
L
p
PARAMETERTEST CONDITIONSMINMAXUNIT
Setup time, address valid before WR↓0ns
Setup time, data valid before WR↑
Hold time, address valid after WR↑
Hold time, data valid after WR↑
Pulse duration, WR low
Pulse duration, LDAC low
C suffix070°C
A
I suffix–4085°C
VDD = 11.4 V to 16.5 V, VSS = 0 or –5 V45ns
VDD = 11.4 V to 16.5 V, VSS = 0 or –5 V0ns
VDD = 11.4 V to 16.5 V, VSS = 0 or –5 V10ns
VDD = 11.4 V to 16.5 V, VSS = 0 or –5 V50ns
VDD = 11.4 V to 16.5 V, VSS = 0 or –5 V50ns
MINMAXUNIT
11.416.5V
–5.50V
2V
0.8V
2 VDD–4V
2kΩ
4
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
CiIn ut ca acitance, REFA, REFB, REFC, REFD
V
10 V
sine wave at 10 kH
TLC7225C, TLC7225I
QUADRUPLE 8-BIT DIGITAL-TO-ANALOG CONVERTERS
SLAS109A – OCTOBER 1996 – REVISED APRIL 1997
electrical characteristics over recommended operating free-air temperature range
reference inputs (all supply ranges)
PARAMETERTEST CONDITIONSMINTYPMAXUNIT
r
i
dual power supply over recommended supply and reference voltage ranges, AGND = DGND = 0 V (unless
otherwise noted)
I
I
I
DD
I
SS
C
i
Input resistance, REFA, REFB, REFC, REFD1.54kΩ
p
p
Channel-to-channel isolation
ac feedthrough
PARAMETERTEST CONDITIONSMINTYPMAXUNIT
Input current, digitalVI = 0 or V
Supply current, V
Supply current, V
Power supply sensitivity∆VDD = ±5%0.01%/%
Input capacitanceDigital inputs8pF
DD
SS
DAC loaded with all 1s300pF
DAC loaded with all 0s65pF
60dB
=
ref
VI = VIL or VIH, No load1016mA
VI = VIL or VIH, No load410mA
pp
DD
z
70dB
±1µA
single power supply, VDD = 14.25 V to 15.75 V, VSS = AGND = DGND = 0 V, V
PARAMETERTEST CONDITIONSMINTYPMAXUNIT
I
I
C
I
DD
i
Input current, digitalVI = 0 or V
Supply current, V
Power supply sensitivity∆VDD = ±5%0.01%/%
Input capacitanceDigital inputs8pF
DD
VI = VIL or VIH, No load513mA
DD
(A, B, C, D) = 10 V
ref
±1µA
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
5
TLC7225C, TLC7225I
tsSettling time to 1/2 LSB
V
10 V
s
V
V
V
tsSettling time to 1/2 LSB
s
g
QUADRUPLE 8-BIT DIGITAL-TO-ANALOG CONVERTERS
SLAS109A – OCTOBER 1996 – REVISED APRIL 1997
operating characteristics over recommended operating free-air temperature range
dual power supply over recommended supply and reference voltage ranges, AGND = DGND = 0 V (unless
otherwise noted)
PARAMETERTEST CONDITIONSMINTYPMAXUNIT
Slew rate2.5V/µs
Positive full scale
Negative full scale
Resolution8Bits
Total unadjusted errorVDD = 15 V ±5%,V
Integral nonlinearity (INL)VDD = 15 V ±5%,V
Differential nonlinearity (DNL)VDD = 15 V ±5%,V
E
E
Full-scale errorVDD = 15 V ±5%,V
FS
Gain errorVDD = 15 V ±5%,V
G
Temperature coefficient
of gain
Zero-code error±20±80mV
Digital crosstalk or feedthrough glitch