apm8601 Diodes, Inc., apm8601 Datasheet - Page 8

• Manufacturer Part Number: apm8601
• Description: Dual Channel Single Cell Linear Lithium Battery Charger With 28v Ovp And Programmable Charge Timer
• Manufacturer: Diodes, Inc.

Functional Description (continued)
INPUTS
DC
withstand up to 28V without device damage although charging is disabled above 7.5V (typ.).
USB
drawn from USB is selected using the USEL pin, either at 95mA (1 USB power allocation unit) or 475mA (5 USB power
allocation units, High Power). Note that R
affect the Prequal current when charging from USB. This pin will also withstand up to 28V, but charging is disabled above
7.5V (typ.).
USB and USEL will be ignored.
GND
EN
remain in the disabled state. For auto-starting, connect pin 8 directly to GND.
SETI
THM
thermistor, which should be placed as close as possible to the battery cell. If no thermistor is used then this input should be
connected directly to ground. The charger will operate when there is less than 315Ω on this input (i.e., no thermistor
connected); will be disabled when there is between 315Ω and 3.94kΩ; enabled when between 3.94kΩ and 28.3kΩ; and
disabled above 28.3kΩ.
0
APM8601
Document number: DS35138 Rev. 1 - 2
315Ω
Pins 12 and 13 are the DC input. This input will allow charging from input voltages between 4.15V and 7V, and can
Pin 9 is the USB power input. This input will charge with input voltages from 4.15V to 7V. The charging current
If both DC and USB are connected and valid, power will be drawn from DC with charge current set by R
System ground connection.
Pin 8 is the enable pin of the device. When pulled low the device will operate normally. When high, the device will
Pin 2 allows the charge currents to be programmed.
The charge current setting also changes the currents in prequal and top-off modes (being 10% and 7.5% of I
respectively):
This pin can also be used to monitor the battery charging current:
The thermistor connection is on pin 3. This allows the battery temperature to be monitored using a 10k NTC
3.94k
R
THM
IPREQUAL =
Enabled
DUAL CHANNEL SINGLE CELL LINEAR LITHIUM BATTERY
CHARGER WITH 28V OVP and PROGRAMMABLE CHARGE
SETI
has no effect on USB charging currents in the Charge state, but R
RSETI
ICHARGE
150
RSETI =
www.diodes.com
28.3k
8 of 14
=
ICHARGE
VSETI
1500
RSETI
×
1000
Thermistor
ITOPOFF =
Beta
3000
3250
3500
3750
25.1
27.1
29.3
31.7
RSETI
Resistance in kΩ at
0°C
112.5
25°C
10
10
10
10
50°C
4.6
4.3
3.8
4
APM8601
Hot trip Cold Trip
55.1
52.6
50.5
48.6
Typical in °C
© Diodes Incorporated
December 2010
‐3.2
‐1.3
0.5
2.0
SETI
TIMER
CHARGE
does
SETI
.