Datasheet

3
LTC2900
2900f
The ● denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C. V
CC
= 5V, unless otherwise noted. (Note 3)
ELECTRICAL CHARACTERISTICS
Note 1: Absolute Maximum Ratings are those values beyond which the life of
a device may be impaired.
Note 2: All currents into pins are positive, all voltages are referenced to GND
unless otherwise noted.
Note 3: The greater of V1, V2 is the internal supply voltage (V
CC
).
Note 4: Under static no-fault conditions, V1 will necessarily supply quiescent
current. If at any time V2 is larger than V1, V2 must be capable of supplying
TEST CIRCUITS
V1
V2
V3
V4
2900 F01
LTC2900-1
RST
I
SOURCE
1µA
V1
V2
V3
V4
2900 F02
LTC2900-1
RST
I
SINK
2.5mA,
100µA
V1
V2
V3
V4
2900 F03
LTC2900-2
RST
I
SOURCE
200µA
Figure 1. RST V
OH
Test Figure 2. RST V
OL
Test Figure 3. Active Pull-Up
RST V
OH
Test
the quiescent current, programming (transient) current and reference load
current.
Note 5: The RST output pin on the LTC2900-1 has an internal pull-up to V2
of typically 6µA. However, an external pull-up resistor may be used when
faster rise times are required or for V
OH
voltages greater than V2.
Note 6: The push-pull RST output pin on the LTC2900-2 is actively pulled up
to V2.
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
I
V2
V2 Input Current V2 = 3.3V ● 0.8 2 µA
I
V3
V3 Input Current V3 = 2.5V ● 0.52 1.2 µA
V3 = 0.55V (ADJ Mode)
● –15 15 nA
I
V4
V4 Input Current V4 = 1.8V ● 0.34 0.8 µA
V4 = 0.55V (ADJ Mode)
● –15 15 nA
V4 = –0.05V (–ADJ Mode)
● –15 15 nA
I
CRT(UP)
CRT Pull-Up Current V
CRT
= 0V ● –1.4 –2 –2.6 µA
I
CRT(DN)
CRT Pull-Down Current V
CRT
= 1.3V ● 10 20 30 µA
t
RST
Reset Time-Out Period C
RT
= 1500pF ● 579 ms
t
UV
V
X
Undervoltage Detect to RST V
X
Less Than Reset Threshold V
RTX
150 µs
by More Than 1%
V
OL
Output Voltage Low RST I
SINK
= 2.5mA; V1 = 3V, V2 = 3V; ● 0.15 0.4 V
V3, V4 = 0V; V
PG
= 0V
I
SINK
= 100µA; V2 = 1V; V1, V3, V4 = 0V ● 0.05 0.3 V
I
SINK
= 100µA; V1 = 1V; V2, V3, V4 = 0V ● 0.05 0.3 V
V
OH
Output Voltage High RST (LTC2900-1) I
SOURCE
= 1µA ● V2 – 1 V
(Note 5)
Output Voltage High RST (LTC2900-2) I
SOURCE
= 200µA ● 0.8 • V2 V
(Note 6)
Manual Reset Pin
V
IH
PBR Input Threshold High V
CC
= 3.3V to 5.5V ● 1.6 V
V
IL
PBR Input Threshold Low V
CC
= 3.3V to 5.5V ● 0.4 V
t
PBW
PBR Input Pulse Width V
CC
= 3.3V ● 150 ns
t
PBD
Manual Reset Propagation Delay V
CC
= 3.3V, V
PBR
Falling ● 0.1 1 µs
I
PBR
PBR Pull-Up Current V
PBR
= 0V –10 µA