LTC1955EUH Linear Technology, LTC1955EUH Datasheet - Page 19

• Manufacturer Part Number: LTC1955EUH
• Description: IC INTERFACE DL SMART CARD 32QFN
• Manufacturer: Linear Technology

Specifications of LTC1955EUH

• Controller Type: Smart Card Interface
• Interface: 4-Wire Serial
• Voltage - Supply: 1.7 V ~ 5.5 V
• Current - Supply: 10µA
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 32-QFN
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

PACKAGE DESCRIPTION
APPLICATIONS INFORMATION
5.50 0.05
Figure 7. Setting the Undervoltage Trip Point
4.10 0.05
LTC1955
(4 SIDES)
3.50 REF
UNDERV
APPLY SOLDER MASK TO AREAS THAT ARE NOT SOLDERED
NOTE:
1. DRAWING PROPOSED TO BE A JEDEC PACKAGE OUTLINE
2. DRAWING NOT TO SCALE
3. ALL DIMENSIONS ARE IN MILLIMETERS
4. DIMENSIONS OF EXPOSED PAD ON BOTTOM OF PACKAGE DO NOT INCLUDE
5. EXPOSED PAD SHALL BE SOLDER PLATED
6. SHADED AREA IS ONLY A REFERENCE FOR PIN 1 LOCATION
23
M0-220 VARIATION WHHD-(X) (TO BE APPROVED)
MOLD FLASH. MOLD FLASH, IF PRESENT, SHALL NOT EXCEED 0.20mm ON ANY SIDE
ON THE TOP AND BOTTOM OF PACKAGE
RECOMMENDED SOLDER PAD LAYOUT
R1
R2
PIN 1
TOP MARK
(NOTE 6)
Information furnished by Linear Technology Corporation is believed to be accurate and reliable.
However, no responsibility is assumed for its use. Linear Technology Corporation makes no representa-
tion that the interconnection of its circuits as described herein will not infringe on existing patent rights.
3.45 0.05
MAIN SUPPLY
V
TRIP
5.00 0.10
(4 SIDES)
3.45 0.05
= 1.23V (1 + R1/R2)
(Reference LTC DWG # 05-08-1693 Rev D)
0.50 BSC
0.25 0.05
32-Lead Plastic QFN (5mm × 5mm)
1955 F08
0.70 0.05
PACKAGE OUTLINE
UH Package
0.75 0.05
LTC1955
(4-SIDES)
0.00 – 0.05
3.50 REF
0.200 REF
R = 0.05
RST X
TYP
CLK X
V
I/O X
CCX
BOTTOM VIEW—EXPOSED PAD
Figure 8. Additional Components for
Improved Compliance Testing
100Ω
100Ω
100Ω
R = 0.115
3.45 0.10
TYP
1μF
3.45 0.10
20pF
31
0.50 BSC
0.25 0.05
32
20pF
PIN 1 NOTCH R = 0.30 TYP
OR 0.35 45° CHAMFER
(UH32) QFN 0406 REV D
20pF
1
2
0.40 0.10
LTC1955
0.1μF
C7
C3
C2
C1
C5
SOCKET
19
SMART
CARD
1955 F09
1955fb