X45620 Datasheet, PDF (2/20 Pages) Intersil Corporation – Dual Voltage Monitor with Integrated System Battery Switch and EEPROM

X45620
DESCRIPTION (Continued)
The Watchdog Timer provides an independent protec-
tion mechanism for microcontrollers. When the micro-
controller fails to restart a timer within a selectable
time out interval, the device activates the WDO signal.
The user selects the interval from three preset values.
Once selected, the interval does not change, even
after cycling the power.
The device’s low V_CC detection circuitry protects the
user’s system from low voltage conditions, resetting
the system when V_CC (V1MON) falls below the mini-
mum V_CC trip point (V_TRIP1). RESET is asserted until
V_CC returns to proper operating level and stabilizes. A
second voltage monitor circuit tracks the unregulated
supply or monitors a second power supply voltage to
provide a power fail warning. Intersil’s unique circuits
allow the threshold for either voltage monitor to be
reprogrammed to meet special needs or to fine-tune
the threshold for applications requiring higher preci-
sion. (Contact factory for custom V_TRIP options)
PIN CONFIGURATION
20-Pin TSSOP
S0
1
20
S1
2
19
NC
3
18
LOWLINE
4
17
NC
5
16
V2FAIL
6
15
V2MON
7
14
RESET/MR
8
13
WDO
9
12
V_SS
10
11
V_CC (V1MON)
WP
NC
BATT-ON
V_OUT
V_BATT
SCL
NC
NC
SDA
Ordering Information
V_CC Range
4.75–5.5V
V_TRIP1 Range
4.5–4.75V
2.7–5.5V
2.55–2.7V
V_TRIP2 Range
2.55–2.7V
1.7–1.80V
Package
20L TSSOP
20L TSSOP
Operating
Temperature Range
0°C–70°C
-40°C–85°C
0°C–70°C
-40°C–85°C
Part Number
X45620V20
X45620V20I
X45620V20-2.7
X45620V20I-2.7
PIN DESCRIPTION
Pin Name
Function
1
S₀
Device Select Input. This pin has an internal pull down resistor. (>10MΩ typical)
2
S₁
Device Select Input. This pin has an internal pull down resistor. (>10MΩ typical)
3
NC
No internal connections
4 LOWLINE Low V_CC Detect. This open drain output signal goes LOW when V_CC < V_TRIP1 and immediately
goes HIGH when V_CC > V_TRIP1.
5
NC
No internal connections
6
V2FAIL V2 Voltage Fail Output. This open drain output goes LOW when V2MON is less than V_TRIP2 and
goes HIGH when V2MON exceeds V_TRIP2. There is no power-up reset delay circuitry on this pin.
7
V2MON V2 Voltage Monitor Input. When the V2MON input is less than the V_TRIP2 voltage, V2FAIL goes
LOW. This input can monitor an unregulated power supply with an external resistor divider or can
monitor a second power supply with no external components. Connect V2MON to V_SS or V_CC
when not used.
2
FN8250.0
July 29, 2005