Rainbow Electronics DS2770 - Manual (Page 4)

DS2770
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DETAILED PIN DESCRIPTION Table 1
PIN SYMBOL DESCRIPTION
1 UV Battery Undervoltage Detect Output: This pin allows charge of the
battery at a reduced rate when the battery cell voltage is less than the low
battery voltage threshold, V
LB
.
2 CC Charge Control Output: Charge of the battery is controlled through this
pin when battery cell voltage is greater than or equal to V
LB
.
3 VCH Charge Supply Input: The charge source is connected to this pin and is
measured by the DS2770 to determine if a charge source is present.
4, 5, 6 SNS Sense Resistor Connection: Connect to the negative terminal of the
battery pack. In the internal sense resistor configuration, the sense resistor
is connected between VSS and SNS.
8 IS2 Current-Sense Input: This pin is internally connected to SNS through a
10k W resistor. Connect a 0.1mF capacitor between IS2 and IS1 to
complete a lowpass filter.
9 IS1 Current-Sense Input: This pin is internally connected to VSS through a
10k W resistor. Connect a 0.1mF capacitor between IS1 and IS2 to
complete a lowpass filter.
11, 12, 13 VSS Device Ground: Connect directly to the negative terminal of the battery
cell. For the external sense resistor configuration, connect the sense
resistor between VSS and SNS.
14 DQ Data Input/Out: 1-Wire data line. Open-drain output driver. Connect this
pin to the DATA terminal of the battery pack. Pin has an internal pull-
down for sensing disconnection.
15 VIN Voltage Sense Input: The voltage on the battery cell is monitored via this
input pin.
16 VDD Power Supply Input: Input supply voltage for the DS2770 (2.7V to
5.5V)
7, 10 NC Do not connect.