MCP1256 Datasheet, PDF (2/24 Pages) Microchip Technology – Regulated 3.3V, Low-Ripple Charge Pump with Low- Operating Current SLEEP Mode or BYPASS Mode

MCP1256/7/8/9
Package Pinouts
PGOOD 1 ^MCP1256 10 SHDN
SLEEP 2
9 GND
C₂- 3
C₁+ 4
V_OUT 5
8 C₁-
7 V_IN
6 C₂+
LBO 1 ^MCP1257 10 SHDN
SLEEP 2
9 GND
C₂- 3
C₁+ 4
V_OUT 5
8 C₁-
7 V_IN
6 C₂+
PGOOD ₁ ^MCP1258 _{10 SHDN}
BYPASS ₂
9 GND
C₂- 3
C₁+ 4
V_OUT 5
8 C₁-
7 VIN
6 C₂+
LBO 1 ^MCP1259 10 SHDN
BYPASS 2
9 GND
C₂- 3
C₁+ 4
V_OUT 5
8 C₁-
7 V_IN
6 C₂+
Functional Block Diagram
V_IN
C₂- C₂+
C₁- C₁+
840 kΩ
1.5x, 2x Mode
Comparator
+
-
DQ
650 kHz
Osc.
Gate Drives
S1
S5,S7
S6
S4
S1,S3,CE
V_OUT
840 kΩ _CE
S2
Bandgap
Ref.
+
-
720kΩ
480 kΩ
Feedback
Amplifier
GND
S5
S4
S3
S6
S7
V_OUT
TABLE 1: SWITCH LOGIC
Mode Phase Oscillator
Q
S1 S2(CE) S3
S4
S5
S6
S7
1.5x Charging
H
L
H
H
H
L
H
L
H
1.5x Transfer
L
L
L
L
L
H
L
H
L
2x Charging
H
H
H
H
H
L
L
H
L
2x Transfer
L
H
L
L
L
H
L
H
L
BYPASS —
—
—
H
L
H
H
H
L
L
Legend: L is Logic Low, H is Logic High
DS21989A-page 2
© 2006 Microchip Technology Inc.