CAT522
Configured Digitally Programmable Potentiometer (DPP™): Programmable Voltage Applications
H
GEN FR ALO
EE
LE
FEATURES
s Two 8-bit DPPs configured as programmable
A D F R E ETM
APPLICATIONS
s Automated product calibration. s Remote control adjustment of equipment s Offset, gain and zero adjustments in self-
voltage sources in DAC-like applications
s Independent reference inputs s Non-volatile NVRAM memory wiper storage s Output voltage range includes both supply rails s 2 independently addressable buffered
calibrating and adaptive control systems.
s Tamper-proof calibrations. s DAC (with memory) substitute.
output wipers
s 1 LSB accuracy, high resolution s Serial Microwire-like interface s Single supply operation: 2.7V - 5.5V s Setting read-back without effecting outputs
DESCRIPTION
The CAT522 is a dual, 8-bit digitally-programmable potentiometer (DPP™) configured for programmable voltage and DAC-like applications. Intended for final calibration of products such as camcorders, fax machines and cellular telephones on automated high volume production lines, it is also well suited for self-calibrating systems and for applications where equipment which requires periodic adjustment is either difficult to access or in a hazardous environment. The CAT522 offers two independently programmable DPPs each having its own reference inputs and each capable of rail to rail output swing. The wipers are buffered by rail to rail opamps. Wiper settings, stored in non-volatile NVRAM memory, are not lost when the device is powered down and are automatically reinstated when power is returned. Each wiper can be FUNCTIONAL DIAGRAM
RDY/BSY V DD VREFH1 VREFH2 14 13
dithered to test new output values without effecting the stored settings and stored settings can be read back without disturbing the DPP's output. The CAT522 is controlled with a simple 3-wire, microwirelike serial interface. A Chip Select pin allows several devices to share a common serial interface. Communication back to the host controller is via a single serial data line thanks to the CAT522 Tri-Stated Data Output pin. A RDY/BSY output working in concert with an internal low voltage detector signals proper operation of the non-volatile NVRAM memory Erase/Write cycle. The CAT522 is available in the 0°C to 70°C commercial and -40°C to 85°C industrial operating temperature ranges. Both 14-pin plastic DIP and surface mount packages are available. PIN CONFIGURATION
DIP Package (P, L)
VDD CLK 1 2 3 4 5 6 7
CAT522
SOIC Package (J, W)
VDD CLK 1 2 3 4 5 6 7
CAT522
3
1
PROG
7
PROGRAM CONTROL
14 13 12 11 10 9 8
VREFH1 VREFH2
14 13 12 11 10 9 8
VREFH1 VREFH2 VOUT1 VOUT2 VREFL2 VREFL1 GND
DI
5 WIPER CONTROL REGISTERS AND NVRAM
24kΩ
+
24KΩ
11
V OUT2
RDY/BSY CS
CLK
2
SERIAL CONTROL
VOUT1 RDY/BSY VOUT2 VREFL2 VREFL1 GND CS DI DO PROG
CS
4
+
12
V OUT1
DI DO
SERIAL DATA OUTPUT REGISTER 6 DO
PROG
CAT522
8
GND
9
10
VREFL1 VREFL2
© 2004 by Catalyst Semiconductor, Inc. Characteristics subject to change without notice
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Doc. No. 2004, Rev. E
CAT522
ABSOLUTE MAXIMUM RATINGS Supply Voltage* VDD to GND ...................................... -0.5V to +7V Inputs CLK to GND ............................ -0.5V to VDD +0.5V CS to GND .............................. -0.5V to VDD +0.5V DI to GND ............................... -0.5V to VDD +0.5V RDY/BSY to GND ................... -0.5V to VDD +0.5V PROG to GND ........................ -0.5V to VDD +0.5V VREFH to GND ........................ -0.5V to VDD +0.5V VREFL to GND ......................... -0.5V to VDD +0.5V Outputs D0 to GND ............................... -0.5V to VDD +0.5V VOUT 1– 4 to GND ................... -0.5V to VDD +0.5V RELIABILITY CHARACTERISTICS Symbol
VZAP(1) ILTH(1)(2)
Operating Ambient Temperature Commercial (‘C’ or Blank suffix) ...... 0°C to +70°C Industrial (‘I’ suffix) ........................ -40°C to +85°C Junction Temperature ..................................... +150°C Storage Temperature ........................ -65°C to +150°C Lead Soldering (10 sec max) .......................... +300°C
* Stresses above those listed under Absolute Maximum Ratings may cause permanent damage to the device. Absolute Maximum Ratings are limited values applied individually while other parameters are within specified operating conditions, and functional operation at any of these conditions is NOT implied. Device performance and reliability may be impaired by exposure to absolute rating conditions for extended periods of time.
Parameter
ESD Susceptibility Latch-Up
Min
2000 100
Max
Units
Volts mA
Test Method
MIL-STD-883, Test Method 3015 JEDEC Standard 17
NOTES: 1. This parameter is tested initially and after a design or process change that affects the parameter. 2. Latch-up protection is provided for stresses up to 100mA on address and data pins from –1V to VCC + 1V.
POWER SUPPLY Symbol Parameter IDD1 IDD2 Supply Current (Read) Supply Current (Write) Conditions Normal Operating Programming, VDD = 5V VDD = 3V VDD Operating Voltage Range Min — — — 2.7 Typ 400 1600 1000 — Max 600 2500 1600 5.5 Units µA µA µA V
LOGIC INPUTS Symbol IIH IIL VIH VIL Parameter Input Leakage Current Input Leakage Current High Level Input Voltage Low Level Input Voltage Conditions VIN = VDD VIN = 0V Min — — 2 0 Typ — — — — Max 10 -10 VDD 0.8 Units µA µA V V
LOGIC OUTPUTS Symbol Parameter VOH VIL High Level Output Voltage Low Level Output Voltage Conditions IOH = -40µA IOL = 1 mA, VDD = +5V IOL = 0.4 mA, VDD = +3V Min VDD -0.3 — — Typ — — — Max — 0.4 0.4 Units V V V
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CAT522
POTENTIOMETER CHARACTERISTICS VDD = +2.7V to +5.5V, VREFH = VDD, VREFL = 0V, unless otherwise specified Symbol RPOT Parameter Potentiometer Resistance RPOT to RPOT Match Pot Resistance Tolerance Voltage on VREFH pin Voltage on VREFL pin Resolution INL DNL ROUT IOUT TCRPOT CH/CL Integral Linearity Error Differential Linearity Error Buffer Output Resistance Buffer Output Current TC of Pot Resistance Potentiometer Capacitances 300 8/8 2.7 0V 0.4 0.5 0.25 1 0.5 10 3 — Conditions Min Typ 24 +0.5 +1 +20 VDD VDD - 2.7 Max Units kΩ % % V V % LSB LSB Ω mA ppm/˚C pF
AC ELECTRICAL CHARACTERISTICS: VDD = +2.7V to +5.5V, VREFH = VDD, VREFL = 0V, unless otherwise specified Symbol Digital
tCSMIN tCSS tCSH tDIS tDIH tDO1 tDO0 tHZ tLZ tBUSY tPS tPROG tCLKH tCLKL fC Minimum CS Low Time CS Setup Time CS Hold Time DI Setup Time DI Hold Time Output Delay to 1 Output Delay to 0 Output Delay to High-Z Output Delay to Low-Z Erase/Write Cycle Time PROG Setup Time Minimum Pulse Width Minimum CLK High Time Minimum CLK Low Time Clock Frequency DPP Settling Time to 1 LSB 150 100 0 50 50 — — — — — 150 700 500 300 DC — — — — — — — — — 400 400 4 — — — — — 3 6 — — — — — 150 150 — — 5 — — — — 1 10 10 ns ns ns ns ns ns ns ns ns ms ns ns ns ns MHz µs µs
Parameter
Conditions
Min
Typ
Max
Units
CL=100pF, see note 1
Analog
tDS CLOAD = 10 pF, VDD = +5V CLOAD = 10 pF, VDD = +3V
NOTES: 1. All timing measurements are defined at the point of signal crossing VDD / 2. 2. These parameters are periodically sampled and are not 100% tested.
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CAT522
A. C. TIMING DIAGRAM
to
1
2
3
4
5
t CLK H CLK
t CSS CS
t CLK L
t CSH
t CSMIN
t DIS DI t DIH
t LZ DO
t DO0
t HZ t DO1
PROG t PS t PROG RDY/BSY t BUSY
to
1
2
3
4
5
Doc. No. 2004, Rev. E
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CAT522
PIN DESCRIPTION Pin
1 2 3 4 5 6 7 8 9 10 11 12 13 14
DPP addressing is as follows: Function
Power supply positive Clock input pin Ready/Busy output Chip select Serial data input pin Serial data output pin EEPROM Programming Enable Input Power supply ground Minimum DPP 1 output voltage Minimum DPP 2 output voltage DPP 2 output DPP 1 output Maximum DPP 2 output voltage Maximum DPP 1 output voltage
Name
VDD CLK RDY/BSY CS DI DO PROG GND VREFL1 VREFL2 VOUT2 VOUT1 VREFH2 VREFH1
DPP OUTPUT VOUT1 VOUT2
A0 0 1
A1 1 1
DEVICE OPERATION The CAT522 is a dual 8-bit configured digitally programmable potentiometer (DPP) whose outputs can be programmed to any one of 256 individual voltage steps. Once programmed, these output settings are retained in non-volatile memory and will not be lost when power is removed from the chip. Upon power up the DPPs return to the settings stored in non-volatile memory. Each DPP can be written to and read from independently without effecting the output voltage during the read or write cycle. Each output can also be adjusted without altering the stored output setting, which is useful for testing new output settings before storing them in memory. DIGITAL INTERFACE The CAT522 employs a 3 wire serial, Microwire-like control interface consisting of Clock (CLK), Chip Select (CS) and Data In (DI) inputs. For all operations, address and data are shifted in LSB first. In addition, all digital data must be preceded by a logic “1” as a start bit. The DPP address and data are clocked into the DI pin on the clock’s rising edge. When sending multiple blocks of information a minimum of two clock cycles is required between the last block sent and the next start bit. Multiple devices may share a common input data line by selectively activating the CS control of the desired IC. Data Outputs (DO) can also share a common line because the DO pin is Tri-Stated and returns to a high impedance when not in use.
CHIP SELECT Chip Select (CS) enables and disables the CAT522’s read and write operations. When CS is high data may be read to or from the chip, and the Data Output (DO) pin is active. Data loaded into the DPP control registers will remain in effect until CS goes low. Bringing CS to a logic low returns all DPP outputs to the settings stored in nonvolatile memory and switches DO to its high impedance Tri-State mode. Because CS functions like a reset the CS pin has been desensitized with a 30 ns to 90 ns filter circuit to prevent noise spikes from causing unwanted resets and the loss of volatile data. CLOCK The CAT522’s clock controls both data flow in and out of the IC and non-volatile memory cell programming. Serial data is shifted into the DI pin and out of the DO pin on the clock’s rising edge. While it is not necessary for the clock to be running between data transfers, the clock must be operating in order to write to non-volatile memory, even though the data being saved may already be resident in the DPP wiper control register. No clock is necessary upon system power-up. The CAT522’s internal power-on reset circuitry loads data from non-volatile memory to the DPPs without using the external clock.
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CAT522
As data transfers are edge triggered clean clock transitions are necessary to avoid falsely clocking data into the control registers. Standard CMOS and TTL logic families work well in this regard and it is recommended that any mechanical switches used for breadboarding or device evaluation purposes be debounced by a flip-flop or other suitable debouncing circuit. VREF VREF, the voltage applied between pins VREFH &VREFL, sets the configured DPP’s Zero to Full Scale output range where VREFL = Zero and VREFH = Full Scale. VREF can span the full power supply range or just a fraction of it. In typical applications VREFH &VREFL are connected across the power supply rails. When using less than the full supply voltage be mindful of the limits placed on VREFL and VREFL as specified in the References section of DC Electrical Characteristics. READY/BUSY When saving data to non-volatile memory, the Ready/ Busy ouput (RDY/BSY) signals the start and duration of the non-volatile erase/write cycle. Upon receiving a command to store data (PROG goes high) RDY/BSY goes low and remains low until the programming cycle is complete. During this time the CAT522 will ignore any data appearing at DI and no data will be output on DO. RDY/BSY is internally ANDed with a low voltage detector circuit monitoring VDD. If VDD is below the minimum value required for non-volatile programming, RDY/BSY will remain high following the program command indicating a failure to record the desired data in non-volatile memory. DATA OUTPUT Data is output serially by the CAT522, LSB first, via the Data Out (DO) pin following the reception of a start bit and two address bits by the Data Input (DI). DO becomes active whenever CS goes high and resumes its high impedance Tri-State mode when CS returns low. Tri-Stating the DO pin allows several 522s to share a Figure 1. Writing to Memory
to 1 2 3 4 5 6 7 8 9 10 11 12 N N+1 N+2
single serial data line and simplifies interfacing multiple 522s to a microprocessor. WRITING TO MEMORY Programming the CAT522’s non-volatile memory is accomplished through the control signals: Chip Select (CS) and Program (PROG). With CS high, a start bit followed by a two bit DPP address and eight data bits are clocked into the DPP wiper control register via the DI pin. Data enters on the clock’s rising edge. The DPP output changes to its new setting on the clock cycle following D7, the last data bit. Programming is accomplished by bringing PROG high sometime after the start bit and at least 150 ns prior to the rising edge of the clock cycle immediately following the D7 bit. Two clock cycles after the D7 bit the DPP wiper control register will be ready to receive the next set of address and data bits. The clock must be kept running throughout the programming cycle. Internal control circuitry takes care of generating and ramping up the programming voltage for data transfer to the non-volatile cells. The CAT522’s non-volatile memory cells will endure over 1,000,000 write cycles and will retain data for a minimum of 100 years without being refreshed. READING DATA Each time data is transferred into a DPP control register currently held data is shifted out via the D0 pin, thus in every data transaction a read cycle occurs. Note, however, that the reading process is destructive. Data must be removed from the register in order to be read. Figure 2 depicts a Read Only cycle in which no change occurs in the DPP’s output. This feature allows µPs to poll DPPs for their current setting without disturbing the output voltage but it assumes that the setting being read is also stored in non-volatile memory so that it can be restored at the end of the read cycle. In Figure 2 CS returns low before the 13th clock cycle completes. In doing so the non-volatile memory setting is reloaded into the DPP wiper control register. Since this value is the Figure 2. Reading from Memory
to 1 2 3 4 5 6 7 8 9 10 11 12
CS NEW DPP DATA DI 1 A0 A1 D0 D1 D2 D3 D4 D5 D6 D7
CS
DI
1
A0
A1 CURRENT DPP DATA
CURRENT DPP DATA DO D0 D1 D2 D3 D4 D5 D6 D7
DO
D0
D1
D2
D3
D4
D5
D6
D7
PROG
PROG
RDY/BSY
RDY/BSY
DPP OUTPUT
CURRENT DPP VALUE
NON-VOLATILE
NEW DPP VALUE
VOLATILE
NEW DPP VALUE
NON-VOLATILE
DPP OUTPUT
CURRENT DPP VALUE
NON-VOLATILE
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CAT522
same as that which had been there previously no change in the DPP’s output is noticed. Had the value held in the control register been different from that stored in nonvolatile memory then a change would occur at the read cycle’s conclusion. TEMPORARILY CHANGE OUTPUT The CAT522 allows temporary changes in DPP’s output to be made without disturbing the settings retained in non-volatile memory. This feature is particularly useful when testing for a new output setting and allows for user adjustment of preset or default values without losing the original factory settings. Figure 3 shows the control and data signals needed to effect a temporary output change. DPP wiper settings may be changed as many times as required and can be made to any of the two DPPs in any order or sequence. The temporary setting(s) remain in effect long as CS remains high. When CS returns low all two DPPs will return to the output values stored in non-volatile memory. When it is desired to save a new setting acquired using this feature, the new value must be reloaded into the DPP wiper control register prior to programming. This is because the CAT522’s internal control circuitry discards from the programming register the new data two clock cycles after receiving it if no PROG signal is received. APPLICATION CIRCUITS
DPP INPUT
+5V Vi Ri +15V VDD CONTROL & DATA VREFH RF
Figure 3. Temporary Change in Output
to 1 2 3 4 5 6 7 8 9 10 11 12 N N+1 N+2
CS
NEW DPP DATA 1 A0 A1 D0 D1 D2 D3 D4 D5 D6 D7
DI
CURRENT DPP DATA DO D0 D1 D2 D3 D4 D5 D6 D7
PROG
RDY/BSY
DPP OUTPUT
CURRENT DPP VALUE
NON-VOLATILE
NEW DPP VALUE
VOLATILE
CURRENT DPP VALUE
NON-VOLATILE
DPP OUTPUT CODE VDPP = ——— (VFS - VZERO ) + V ZERO 255 VFS = 0.99 VREF VZERO = 0.01 V REF 255 —— (.98 VREF) + .01 VREF = .990 V REF 255 128 —— (.98 V ) + .01 V = .502 V REF REF REF 255 127 (.98 V —— ) + .01 V = .498 V 255 REF REF REF 1 —— (.98 V ) + .01 V = .014 V 255 REF REF REF 0 —— (.98 V ) + .01 V = .010 V REF REF REF 255
ANALOG OUTPUT
MSB
LSB 1111
– + OP 07
VOUT
VREF = 5V R I = RF V OUT= +4.90V V V V = +0.02V = -0.02V = -4.86V
1111
CAT522
GND VREFL
-15V
1000 0111
0000 1111 0001
OUT OUT OUT
VOUT = V DPP ( R i+ RF) -Vi R F Ri For R i = RF VOUT = 2VDPP -Vi
0000
0000
0000
V
OUT
= -4.90V
Bipolar DPP Output
+5V RI +15V VDD CONTROL & DATA VREFH RF
– + OP 07
VOUT
CAT522
GND VREFL
-15V
RF VOUT = (1 + –––) V DPP RI
Amplified DPP Output 7
Doc. No. 2004, Rev. E
CAT522
APPLICATION CIRCUITS (Cont.)
VREF RC = ————— 256 * 1 µA +5V VREF VREFH Fine adjust gives ± 1 LSB change in V OFFSET VREF when V OFFSET = ——— 2 127RC
+5V +VREF VREFH
VDD
VDD
FINE ADJUST DPP
127RC + (+VREF ) - (VOFFSET ) RC = ——————————— 1 µA
FINE ADJUST DPP
CAT522
COARSE ADJUST DPP RC
CAT522
+V COARSE ADJUST DPP RC V OFFSET
(-VREF ) + (VOFFSET+ ) Ro = ——————————— 1 µA
+ –
GND
VREFL Ro -VREF VOFFSET
+V
+ –
-V
GND
VREFL
Coarse-Fine Offset Control by Averaging DPP Outputs for Single Power Supply Systems
Coarse-Fine Offset Control by Averaging DPP Outputs for Dual Power Supply Systems
28 - 32V
V+
15K
I > 2 mA
10 µF
1N5231B
VDD CONTROL & DATA VREFH VREF = 5.000V
CONTROL & DATA VDD VREFH 5.1V 10K
CAT522
GND VREFL
LT 1029
CAT522
GND VREFL
+ – LM 324
MPT3055EL
OUTPUT 4.02 K 1.00K 10 µF 35V 0 - 25V @ 1A
Digitally Trimmed Voltage Reference
Digitally Controlled Voltage Reference
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CAT522
APPLICATION CIRCUITS (Cont.)
+5V 2.2K VDD VREFH 4.7 µA
LM385-2.5
+15V
ISINK = 2 - 255 mA
DPP
+5V
+ –
10K 10K
2N7000
39 Ω 1W 39 Ω 1W
1 mA steps
CONTROL & DATA
CAT522
DPP
+ 2N7000 –
5 µA steps
GND
VREFL
5M
5M
3.9K
10K
10K
– + TIP 30
-15V
Current Sink with 4 Decades of Resolution
+15V
51K
+ TIP 29 –
10K +5V 10K
VDD
VREFH
5M
5M
39 Ω 1W 39 Ω 1W
DPP
CONTROL & DATA
CAT522
5M
– +
5M
BS170P
1 mA steps
3.9K
DPP
GND
VREFL
– BS170P + LM385-2.5
5 µA steps
-15V
ISOURCE = 2 - 255 mA
Current Source with 4 Decades of Resolution
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CAT522
ORDERING INFORMATION
Prefix CAT Device # 522 Suffix J I -TE13
Optional Company ID
Product Number
Package P: PDIP J: SOIC L: PDIP (Lead free, Halogen free) W: SOIC (Lead free, Halogen free)
Tape & Reel TE13: 2000/Reel
Temperature Range Blank = Commercial (0°C to 70°C) I = Industrial (-40°C to 85°C)
Notes: (1) The device used in the above example is a CAT522JI-TE13 (SOIC, Industrial Temperature, Tape & Reel)
Doc. No. 2004, Rev. E
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CAT522
REVISION HISTORY
Date 3/16/2004 7/12/2004 Rev. D E Reason Updated Potentiometer Characteristics Updated Functional Diagram Updated Potentiometer Characteristics
Copyrights, Trademarks and Patents Trademarks and registered trademarks of Catalyst Semiconductor include each of the following:
DPP ™ AE2 ™
Catalyst Semiconductor has been issued U.S. and foreign patents and has patent applications pending that protect its products. For a complete list of patents issued to Catalyst Semiconductor contact the Company’s corporate office at 408.542.1000.
CATALYST SEMICONDUCTOR MAKES NO WARRANTY, REPRESENTATION OR GUARANTEE, EXPRESS OR IMPLIED, REGARDING THE SUITABILITY OF ITS PRODUCTS FOR ANY PARTICULAR PURPOSE, NOR THAT THE USE OF ITS PRODUCTS WILL NOT INFRINGE ITS INTELLECTUAL PROPERTY RIGHTS OR THE RIGHTS OF THIRD PARTIES WITH RESPECT TO ANY PARTICULAR USE OR APPLICATION AND SPECIFICALLY DISCLAIMS ANY AND ALL LIABILITY ARISING OUT OF ANY SUCH USE OR APPLICATION, INCLUDING BUT NOT LIMITED TO, CONSEQUENTIAL OR INCIDENTAL DAMAGES.
Catalyst Semiconductor products are not designed, intended, or authorized for use as components in systems intended for surgical implant into the body, or other applications intended to support or sustain life, or for any other application in which the failure of the Catalyst Semiconductor product could create a situation where personal injury or death may occur. Catalyst Semiconductor reserves the right to make changes to or discontinue any product or service described herein without notice. Products with data sheets labeled "Advance Information" or "Preliminary" and other products described herein may not be in production or offered for sale. Catalyst Semiconductor advises customers to obtain the current version of the relevant product information before placing orders. Circuit diagrams illustrate typical semiconductor applications and may not be complete.
Catalyst Semiconductor, Inc. Corporate Headquarters 1250 Borregas Avenue Sunnyvale, CA 94089 Phone: 408.542.1000 Fax: 408.542.1200 www.catsemi.com
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Publication #: Revison: Issue date: Type:
2004 E 7/12/04 Final
Doc. No. 2004, Rev. E