AD5383 Analog Devices, AD5383 Datasheet - Page 23

• Manufacturer Part Number: AD5383
• Description: 32-Channel 12-Bit 3 V/5 V Single-Supply Voltage-Output DAC
• Manufacturer: Analog Devices

Specifications of AD5383

• Resolution (bits): 12bit
• Dac Update Rate: 167kSPS
• Dac Settling Time: 6µs
• Max Pos Supply (v): +5.5V
• Single-supply: No
• Dac Type: Voltage Out
• Dac Input Format: Par,Ser,SPI

Table 16. Control Register Contents
MSB
CR11
Control Register Write/Read
REG1 = REG0 = 0, A4 to A0 = 01100, R/ W status determines if
the operation is a write (R/ W = 0) or a read (R/ W = 1). DB11 to
DB0 contains the control register data.
Control Register Contents
CR11: Power-Down Status. This bit is used to configure the
output amplifier state in power down.
CR10: REF Select. This bit selects the operating internal
reference for the AD5383. CR12 is programmed as follows:
CR9: Current Boost Control. This bit is used to boost the
current in the output amplifier, thereby altering its slew rate.
This bit is configured as follows:
CR8: Internal/External Reference. This bit determines if the
DAC uses its internal reference or an externally applied
reference.
CR7: Channel Monitor Enable (see Channel Monitor
Function).
CR11 = 1. Amplifier output is high impedance (default on
power-up).
CR11 = 0. Amplifier output is 100 kΩ to ground.
CR10 = 1: Internal reference is 2.5 V (AD5383-5 default), the
recommended operating reference for AD5383-5.
CR10 = 0: Internal reference is 1.25 V (AD5383-3 default),
the recommended operating reference for AD5383-3.
CR9 = 1: Boost Mode On. This maximizes the bias current in
the output amplifier, optimizing its slew rate but increasing
the power dissipation.
CR9 = 0: Boost Mode Off (default on power-up). This
reduces the bias current in the output amplifier and reduces
the overall power consumption.
CR8 = 1: Internal Reference Enabled. The reference output
depends on data loaded to CR10.
CR8 = 0: External Reference Selected (default on power up).
CR7= 1: Monitor Enabled. This enables the channel monitor
function. After a write to the monitor channel in the SFR
register, the selected channel output is routed to the
MON_OUT pin.
CR10
CR9
CR8
CR7
CR6
Rev. B | Page 23 of 40
CR5
CR6: Thermal Monitor Function. This function is used to
monitor the AD5383’s internal die temperature when enabled.
The thermal monitor powers down the output amplifiers when
the temperature exceeds 130°C. This function can be used to
protect the device in cases where power dissipation may be
exceeded if a number of output channels are simultaneously
short-circuited. A soft power-up will re-enable the output
amplifiers if the die temperature has dropped below 130°C.
CR5 and CR4: Don’t Care.
CR3 to CR0: Toggle Function Enable. This function allows the
user to toggle the output between two codes loaded to the A
and B registers for each DAC. Control Register Bits CR3 to CR0
are used to enable individual groups of eight channels for oper-
ation in toggle mode. A Logic 1 written to any bit enables a
group of channels; a Logic 0 disables a group. LDAC is used to
toggle between the two registers. Logic 1 enables a group of
channels; Logic 0 disables a group of channels.
Table 17.
CR Bit
CR3
CR2
CR1
CR0
Channel Monitor Function
REG1 = REG0 = 0, A4 to A0 = 01010
DB11 to DB6 = Contain data to address the monitored channel.
A channel monitor function is provided on the AD5383. This
feature, which consists of a multiplexer addressed via the
interface, allows any channel output or signals connected to the
MON_IN pins to be routed to the MON_OUT pin for
monitoring using an external ADC. The channel monitor
function must be enabled in the control register before any
channels are routed to MON_OUT. On the AD5383, DB11 to
DB6 contain the channel address for the monitored channel.
Selecting Channel Address 63 three-states MON_OUT.
CR7 = 0: Monitor Disabled (default on power-up). When the
monitor is disabled, the MON_OUT pin is three-stated.
CR6 = 1: Thermal Monitor Enabled.
CR6 = 0: Thermal Monitor Disabled (default on power-up).
CR4
Group
3
2
1
0
CR3
CR2
Channels
24 to 31
16 to 23
8 to 15
0 to 7
CR1
AD5383
LSB
CR0