LTC4008 Datasheet, PDF (3/24 Pages) Linear Technology – 4A, High Efficiency, Multi-Chemistry Battery Charger

LTC4008
ELECTRICAL CHARACTERISTICS The ● denotes specifications which apply over the full operating
temperature range (Note 4), otherwise specifications are at T_A = 25°C. V_DCIN = 20V, V_BAT = 12V unless otherwise noted.
SYMBOL PARAMETER
CONDITIONS
MIN TYP MAX UNITS
Current Sense Amplifier, CA1
Input Bias Current Into BAT Pin
CMSL CA1/I₁ Input Common Mode Low
CMSH CA1/I₁ Input Common Mode High
V_OS
Input Voltage Offset
Current Comparators I_CMP and I_REV
I_TMAX
Maximum Current Sense Threshold (V_CSP – V_BAT)
I_TREV
Reverse Current Threshold (V_CSP – V_BAT)
Current Sense Amplifier, CA2
V_DCIN ≤ 28V
V_ITH = 2.5V
11.66
µA
●0
V
●
V_CLN – 0.2
V
– 3.5
3.5
mV
● 140
165
200
mV
– 30
mV
Transconductance
1
mmho
Source Current
Sink Current
Current Limit Amplifier
Measured at I_TH, V_ITH = 1.4V
Measured at I_TH, V_ITH = 1.4V
– 40
µA
40
µA
Transconductance
1.4
mmho
V_CLP
Current Limit Threshold
I_CLN
CLN Input Bias Current
Voltage Error Amplifier, EA
● 93
100 107
mV
100
nA
Transconductance
1
mmho
V_REF
I_BEA
OVSD
Reference Voltage Used to Calculate V_FLOAT
Input Bias Current
Sink Current
Overvoltage Shutdown Threshold as a Percent
of Programmed Charger Voltage
Measured at I_TH, V_ITH = 1.4V
1.19
V
±4
±25
nA
36
µA
● 102
107
110
%
Input P-Channel FET Driver (INFET) (LTC4008 Only)
DCIN Detection Threshold (V_DCIN – V_CLP)
Forward Regulation Voltage (V_DCIN – V_CLP)
Reverse Voltage Turn-Off Voltage (V_DCIN – V_CLP)
INFET “On” Clamping Voltage (V_CLP – V_INFET)
INFET “Off” Clamping Voltage (V_CLP – V_INFET)
Thermistor
DCIN Voltage Ramping Up
from V_CLP – 0.1V
DCIN Voltage Ramping Down
I_INFET = 1µA
I_INFET = – 25µA
●0
0.17 0.25
V
●
25
50
mV
● – 60 – 25
mV
●5
5.8
6.5
V
0.25
V
NTCVR Reference Voltage During Sample Time
4.5
V
High Threshold
V_NTC Rising
● NTCVR NTCVR NTCVR
V
• 0.48 • 0.5 • 0.52
Low Threshold
V_NTC Falling
● NTCVR NTCVR NTCVR
V
• 0.115 • 0.125 • 0.135
Thermistor Disable Current
Indicator Outputs (ACP/ SHDN, FLAG, I_CL, FAULT
C10TOL FLAG (C/10) Accuracy
I_CL Threshold Accuracy
V_OL
Low Logic Level of ACP/SHDN, FLAG, I_CL, FAULT
V_OH
High Logic Level of ACP/SHDN, I_CL
I_OFF
Off State Leakage Current of FLAG, FAULT
I_PO
Pull-Up Current on ACP/SHDN, I_CL
V_NTC ≤ 10V
Voltage Falling at PROG
V_CLP – V_CLN
I_OL = 100µA
I_OH = –1µA
V_OH = 3V
V = 0V
10
µA
● 0.375 0.397 0.420
V
83
93
105
mV
0.5
V
● 2.7
V
–1
1
µA
– 10
µA
4008fa
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