Maxim Integrated DS4830A Optical Microcontroller - Manual (Page 73)

DS4830A User’s Guide
73
SECTION 9 – QUICK TRIP (FAST COMPARATOR)
The DS4830A has 10-bit quick trips with a 16-input analog MUX (Figure 9-1). The MUX selects the quick trip analog
input from 16 external channels. The quick trip external channels can be configured to operate as eight fully
differential inputs or sixteen single-ended inputs. The quick trip monitors all configured quick trip channels in a round
robin sequence.
QT CONFIGURATIONS
ADC-S0
ADC-S1
ADC-S14
ADC-S15
A
N
A
L
O
G
M
U
X
QT SEQUENCER
QTSTART QTEND QTEN
QT HIGH
THRESHOLD
QT LOW
THRESHOLD
CHSEL[3:0] DIFF
Digital MUX
10-Bit
Internal
DAC
HT Register[0]
HT Register[14]
HT Register[1]
HT Register[15]
16 High Threshold
Registers
LT Register[0]
LT Register[14]
LT Register[1]
LT Register[15]
16 Low Threshold
Registers
LIST REGISTER[0]
LIST REGISTER[14]
LIST REGISTER[1]
LIST REGISTER[15]
16 List Configurations
5 bit Each
LTI / HTI LTIE / HTIE
Interrupt
QT CLOCK
QTDATA[15:0]
Comparator
QT- 2.42V
Internal
Reference
.
.
.
RW_LST = 0
LTHT = 0
RW_LST = 1
.
.
.
.
.
.
RW_LST = 0
LTHT = 1
Figure 9-1: Quick Trip Functional Diagram
9.1 – Detailed Description
As shown in Figure 9-1, the DS4830A Quick Trip (QT) controller has a 16-input analog MUX and Quick Trip
Sequencer. The QT sequencer creates a list of configurations and sets user defined low and high threshold for
external channels. The quick trip controller has 16 low trip threshold and 16 high trip threshold internal registers.
The Quick Trip Control Register (QTCN) has two bits RW_LST and LTHT which are used to configure thresholds
and list creation. The QTIDX[3:0] bits (located in the QTCN register) together with LTHT and RW_LST bits select the
source or destination address for the QTDATA register access. Figure 9-1 illustrates the threshold configuration and
list creation.