Parallel Connection (Boosting Capacity Increase) - Epson S1F76540M0C Series Technical Manual

9.7 Parallel Connection (Boosting Capacity Increase)

The parallel connection is effective when lowering the boosting output impedance or reducing the ripple voltage.
Connecting n S1F76540s in parallel sets the boosting output impedance to approximately 1/n. Only the
smoothing capacitor CO for boosting output can be shared even in parallel connection.
Using the regulator allows you to operate only one of n S1F76540s that are connected in parallel. (Running
multiple regulators in parallel will generate the reactive consumption current.)
Figure 9.8 shows a "quadruple boosting + regulator" connection example where two S1F76540s are connected
in parallel.
Master IC
CO
+
1 VO
2
VRI
3
V
REG
4
RV
V
DD
5
V
DD
+
6
FC
7
CI TC1
8 TC2
VI
Figure 9.8 Setting conditions
Master IC
Internal clock
Booster
Regulator
Power-off method
In the connection example shown in Figure 9.8, setting S1F76540 in the master IC to POFF2X = L (VI)
enables you to stop boosting the master and slave ICs; however, the regulator in the slave IC does not stop.
When |V | is greater than |VI|, the voltage that is equivalent to VI is generated in the V
REG
When placing the V
REG
and POFF2X = L.
Other setting conditions
(1) When using the high output mode
Connect the FC pin in the master IC to VI.
(2) When changing the temperature coefficient CT
Change the TC1 and TC2 pins in the slave IC as shown in Table 5.3.
S1F76540M0C Series Technical Manual
(Rev.1.1)
9. REFERENCE: EXTERNAL CONNECTION EXAMPLES
+
C2P 16
15
C2N C2
C3
14
C3N
C1 +
13
C1N
+
12
C1P
11
VI
10
POFF1X
POFF2X
9
Figure 9.8 Parallel connection example
: ON (Low output mode)
: ON
: OFF
pin into the high impedance state, set both the master and slave ICs to POFF1X = L
V
REG
1
CREG
+
2
R1 R2
3
4
5
6
7
8
Slave IC
Internal clock : OFF (Clocks supplied from master IC)
Booster : ON
Regulator : ON (Select CT0 = -0.05%/°C.)
EPSON
Slave IC
VO C2P 16
+
VRI C2N 15 C2'
V C3N 14
REG
C1'
RV C1N 13
+
V C1P 12
DD
FC VI 11
TC1 POFF1X 10
TC2 9
POFF2X
pin.
REG
C3'
+
25