ADM1169 Analog Devices, ADM1169 Datasheet - Page 14

• Manufacturer Part Number: ADM1169
• Description: Super Sequencer and Monitor with Margining Control and Non-Volatile Fault Recording
• Manufacturer: Analog Devices

Specifications of ADM1169

• # Supplies Monitored: 8
• Volt Monitoring Accuracy: 1%
• # Output Drivers: 8
• Fet Drive/enable Output: Both
• Voltage Readback: 12-bit ADC
• Supply Adj/margining: 12-bit ADC+4 DACs
• Package: 32 ld LQFP,40 ld LFCSP

ADM1169
INPUTS
SUPPLY SUPERVISION
The ADM1169 has eight programmable inputs. Four of these are
dedicated supply fault detectors (SFDs). These dedicated inputs
are called VH and VPx (VP1 to VP3) by default. The other four
inputs are labeled VXx (VX1 to VX4) and have dual functionality.
They can be used either as SFDs, with functionality similar to the
VH and VPx, or as CMOS-/TTL-compatible logic inputs to the
device. Therefore, the ADM1169 can have up to eight analog
inputs, a minimum of four analog inputs and four digital inputs,
or a combination thereof. If an input is used as an analog input,
it cannot be used as a digital input. Therefore, a configuration
requiring eight analog inputs has no available digital inputs.
Table 6 shows the details of each input.
PROGRAMMING THE SUPPLY FAULT DETECTORS
The ADM1169 can have up to eight SFDs on its eight input
channels. These highly programmable reset generators enable
the supervision of up to eight supply voltages. The supplies can
be as low as 0.573 V and as high as 14.4 V. The inputs can be
configured to detect an undervoltage fault (the input voltage
drops below a preprogrammed value), an overvoltage fault (the
input voltage rises above a preprogrammed value), or an out-of-
window fault (the input voltage is outside a preprogrammed
range). The thresholds can be programmed to an 8-bit resolution
in registers provided in the ADM1169. This translates to a voltage
resolution that is dependent on the range selected. The resolution
is given by
Therefore, if the high range is selected on VH, the step size can
be calculated as follows:
Step Size = Threshold Range/255
(14.4 V − 6.0 V)/255 = 32.9 mV
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Table 5 lists the upper and lower limits of each available range,
the bottom of each range (V
Table 5. Voltage Range Limits
Voltage Range (V)
0.573 to 1.375
1.25 to 3.00
2.5 to 6.0
6.0 to 14.4
The threshold value required is given by
where:
V
V
N is the decimal value of the 8-bit code.
V
Reversing the equation, the code for a desired threshold is given by
For example, if the user wants to set a 5 V overvoltage threshold
on VP1, the code to be programmed in the PS1OVTH register
(as described in the
Therefore, N = 182 (1011 0110 or 0xB6).
T
R
B
is the desired threshold voltage (undervoltage or overvoltage).
is the voltage range.
is the bottom of the range.
V
N = 255 × (V
N = 255 × (5 − 2.5)/3.5
T
= (V
R
× N)/255 + V
T
AN-721 Application
− V
B
)/V
R
B
B
), and the range itself (V
Note) is given by
V
0.573
1.25
2.5
6.0
B
(V)
R
).
V
0.802
1.75
3.5
8.4
R
(V)