Features: ·3 Output Types: Push/Pull RESET, Push Pull RESETN, and Open Drain RESETN
·Reset Threshold Range: 1.6 to 2.5V (~100mV increments)
·RESET/RESETN:
- Valid to VCC = 0.7V (AS1907 and AS1908)
- Valid to VCC = 1.0V (AS1909)
·Reset Pulse Widths: 1, 20, and 100ms
·Supply Voltage Range: +0.7 to +3.6V
·Supply Current Range: 2.6 to 7.0µA
·Power Supply Transient Immunity
·Requires No External Components
·Operating Temperature Range: -40 to +125ºC
·3-pin SOT23 PackageApplicationThe devices are ideal for use in cordless and mobile phones, MP3 players, CD and DVD players, PDAs, handheld computers, digital cameras, hard drives, and any other application where power supply supervisory control is required.
Pinout
Specifications
| Parameter |
Min |
Max |
Units |
Comments |
|
VCC
RESET, RESETN Push/Pull
RESETN Open Drain
Input Current (VCC)
Output Current (RESET, RESETN) |
-0.3
-0.3
-0.3
|
+5
VCC + 0.3
+6
20
20 |
V
V
V
mA
mA |
|
|
Continuous Power Dissipation
(TAMB = +70ºC) |
|
320 |
mW |
3-pin SOT23 derate 4mW/ºC above +70ºC |
|
Operating Temperature Range
Storage Temperature Range |
-40
-65 |
+125
+160 |
ºC
ºC |
|
|
Package Body Temperature |
|
+260 |
ºC |
The reflow peak soldering temperature (body
temperature) specified is in accordance with
IPC/JEDEC J-STD-020C "Moisture/Reflow
Sensitivity Classification for Non-Hermetic
Solid State Surface Mount Devices" |
DescriptionThe AS1907/AS1908/AS1909 microprocessor supervisory circuits are ideal for monitoring the supply voltage of digital systems and microprocessors.
The AS1908 is designed to initiate a reset if the supply voltage goes below a predefined threshold. The duration of the reset is either 1.5, 30, or 150ms (typ.) after the supply voltage has risen above the pre-set threshold (see Ordering Information on page 9).
The devices are available as the standard products listed in Table 1.
The AS1907/AS1908/AS1909 microprocessor supervisory circuits are ideal for monitoring the supply voltage of digital systems and microprocessors.
The devices are designed to initiate a reset if the supply voltage goes below a predefined threshold. The duration of the reset is either 1.5, 30, or 150ms (typ.) after the supply voltage has risen above the pre-set threshold.
The devices are available as the following standard products:
|
Model |
Output Type |
Reset Type |
|
AS1907 |
Push/Pull |
Active-Low |
|
AS1908 |
Push/Pull |
Active-High |
|
AS1909 |
Open-Drain |
Active-Low |
The reset thresholds are factory-set between 1.6 and 2.5V in steps of approximately 100mV.
The AS1908 exhibit excellent reliability, and can reduce system costs by eliminating the need for external components. The extremely low current consumption makes the devices ideal for use in portable applications.
The integrated reset comparator was specifically designed to ignore fast transients on VCC.
The AS1908 is available in a 3-pin SOT23 package.
AS1908 Data Sheet
