DS1306_05 Datasheet, PDF (8/21 Pages) Dallas Semiconductor – Serial Alarm Real-Time Clock

STATUS REGISTER (READ 10H)
BIT7
BIT6
BIT5
BIT4
0
0
0
0
BIT3
0
DS1306
BIT2
0
BIT1
IRQF1
BIT0
IRQF0
IRQF0 (Interrupt 0 Request Flag) – A logic 1 in the interrupt request flag bit indicates that the current
time has matched the Alarm 0 registers. If the AIE0 bit is also a logic 1, the INT0 pin goes low. IRQF0 is
cleared when the address pointer goes to any of the Alarm 0 registers during a read or write. IRQF0 is
activated when the device is powered by V_CC1, V_CC2, or V_BAT.
IRQF1 (Interrupt 1 Request Flag) – A logic 1 in the interrupt request flag bit indicates that the current
time has matched the Alarm 1 registers. If the AIE1 bit is also a logic 1, the INT1 pin generates a 62.5ms
active-high pulse. IRQF1 is cleared when the address pointer goes to any of the alarm 1 registers during a
read or write. IRQF1 is activated only when the device is powered by V_CC2 or V_BAT.
TRICKLE CHARGE REGISTER (READ 11H, WRITE 91H)
This register controls the trickle charge characteristics of the DS1306. The simplified schematic of Figure
3 shows the basic components of the trickle charger. The trickle charge select (TCS) bits (bits 4–7)
control the selection of the trickle charger. In order to prevent accidental enabling, only a pattern of 1010
enables the trickle charger. All other patterns disable the trickle charger. The DS1306 powers up with the
trickle charger disabled. The diode select (DS) bits (bits 2–3) select whether one diode or two diodes are
connected between V_CC1 and V_CC2. The diode select (DS) bits (bits 2–3) select whether one diode or two
diodes are connected between V_CC1 and V_CC2. The resistor select (RS) bits select the resistor that is
connected between V_CC1 and V_CC2. The resistor and diodes are selected by the RS and DS bits as shown
in Table 2.
Figure 3. PROGRAMMABLE TRICKLE CHARGER
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