TC7660EOA Microchip Technology, TC7660EOA Datasheet - Page 9

• Manufacturer Part Number: TC7660EOA
• Description: IC CHARGE PUMP DC/DC CONV 8-SOIC
• Manufacturer: Microchip Technology
• Type: Switched Capacitor (Charge Pump), Invertingr

Specifications of TC7660EOA

• Package / Case: 8-SOIC (3.9mm Width)
• Internal Switch(s): Yes
• Synchronous Rectifier: No
• Number Of Outputs: 1
• Voltage - Output: -1.5 ~ -10 V
• Current - Output: 20mA
• Frequency - Switching: 10kHz
• Voltage - Input: 1.5 ~ 10 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Power - Output: 470mW
• Minimum Operating Temperature: - 40 C
• Mounting Style: SMD/SMT
• Function: Inverting
• Output Voltage: - 10 V to - 1.5 V
• Output Current: 20 mA
• Maximum Operating Temperature: + 85 C
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Lead free / RoHS Compliant

FIGURE 5-7:
Converter And Positive Multiplier.
5.7
Since the switches that allow the charge pumping
operation are bidirectional, the charge transfer can be
performed
Figure 5-8 shows a TC7660 transforming -5V to +5V
(or +5V to +10V, etc.). The only problem here is that the
internal clock and switch-drive section will not operate
until some positive voltage has been generated. An ini-
tial inefficient pump, as shown in Figure 5-7, could be
used to start this circuit up, after which it will bypass the
other (D
else the diode and resistor shown dotted in Figure 5-8
can be used to "force" the internal regulator on.
FIGURE 5-8:
Conversion.
10 µF
2002 Microchip Technology Inc.
+
C
C
1
1
1
+
1
2
3
4
Efficient Positive Voltage
Multiplication/Conversion
and D
TC7660
backwards
1
2
3
4
2
C
in Figure 5-7 would never turn on), or
TC7660
2
+
8
7
6
5
Combined Negative
Positive Voltage
as
8
7
6
5
V
+
V
OUT
1 M
easily
= -V
V
D
D
-
1
2
input
-
V
(2 V
as
+
+
OUT
+
C
C
) - (2 V
+
=
forwards.
3
4
10 µF
V
= -V
OUT
F
+
)
TC7660
DS21465B-page 9