Ac electrical characteristics, Electrical characteristics: charging – Rainbow Electronics DS2715 User Manual
Page 3

DS2715: NiMH Cell Pack Charge Controller
3 of 12
AC ELECTRICAL CHARACTERISTICS
(4.5V
£ V
DD
£ 16.5V, T
A
= 0
°C to +70°C, unless otherwise noted.)
PARAMETER SYMBOL CONDITIONS MIN
TYP
MAX
UNITS
UVLO Debounce Time
t
UVLO
10
µs
Current Sense
Comparator Propagation
Delay
t
COMP
(Note
7)
250 ns
Discharge Detect
Propagation Delay
t
DD
From detection of current
reversal
1
µs
Return To Normal
Function (Op-Amp or
Comparator Mode)
t
RNF
Time from reset of
discharge latch
1
µs
R
T
Timing Accuracy
t
Rt
(Note
4)
-10 +10 %
Internal Clock Accuracy
t
BASE
-10
+10 %
ELECTRICAL CHARACTERISTICS: CHARGING
(4.5V
£ V
DD
£ 16.5V, T
A
= 0
°C to +70°C, unless otherwise noted.)
PARAMETER SYMBOL CONDITIONS MIN
TYP
MAX
UNITS
Fast Charge Comparator
Threshold
V
FC
Fast
charge
-127 -121 -115 mV
Fast Charge Comparator
Hysteresis
V
HYS-FC
Fast
charge
-31 -28 -25 mV
Top-off and Pre-Charge
Comparator Threshold
V
TO
Top-off and pre-charge
-38
-33
-28
mV
Top-off and Pre-Charge
Comparator Hysteresis
V
HYS-TO
Top-off and pre-charge
-10
-8
-6
mV
Discharge Latch Reset
Threshold
V
DCHG-RST
-15
-10
-5
mV
Discharge Latch Set
Threshold
V
DCHG-SET
Reverse current through
sense resistor
5 10 15 mV
Low Battery Detect
Threshold
V
LB
From presence detect into
pre-charge
0.95 1.0 1.05 V
Cell Detect Threshold
V
DET
1.50 1.55 1.60 V
No Cell Detect Threshold
V
OPEN
1.60 1.65 1.70 V
Presence Detect
Threshold Hysteresis
V
HYS-PD
90
100 110
mV
2.88 2.92 2.96 V
Minimum Charge Temp
V
THM-MIN
(Note 5, 6)
0 ºC
1.28 1.32 1.36 V
Maximum Charge Temp
V
THM-MAX
(Note 5, 6)
45 ºC
1.12 1.16 1.20 V
Over Temp
V
THM-STOP
(Note 5, 6)
50 ºC
dT/dt Detect
T
TERM
0.425 0.5 0.575 ºC/min
dT/dt Blanking Time
t
BLANK
3.85 4.3 4.75 Min
Fast Charge Timer
Range
t
FC
0.5
6 Hours
Top-Off to Fast Charge
Duration Ratio
1:2